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BACKGROUND: The present study examined the effect of liposomes conjugated with antisense oligonucleotide of nerve growth factor (NGF-OND) on local overexpression of NGF and bladder overactivity using rats with prostatic inflammation (PI). METHODS: Male Sprague-Dawley rats were divided into three groups: (1) Control group; intact rats, (2) PI-NS group; rats with PI and intravesical instillation of normal saline (NS), (3) PI-OND group; rats with PI and intravesical instillation of NGF-OND. On Day 0, PI was induced by intraprostatic 5%-formalin injection. On Day 14, NGF-OND or NS was instilled directly into the bladder after laparotomy. On Day 28, therapeutic effects of NGF-OND were evaluated by awake cystometry and histological analysis as well as reverse-transcription polymerase chain reaction measurements of messenger RNA (mRNA) levels of NGF in the bladder and prostate, inflammatory markers in the prostate, C-fiber afferent markers, and an A-type K(+) channel α-subunit (Kv 1.4) in L6-S1 dorsal root ganglia (DRG). RESULTS: Intravesical NFG-OND treatment reduced PI-induced overexpression of NGF in both bladder and prostate, and reduced PI-induced bladder overactivity evident as longer intercontraction intervals in association with reductions of TRPV1 and TRPA1 mRNA expression levels in DRG. mRNA expression of Kv1.4 in DRG was reduced after PI, but improved in the PI-OND group. CONCLUSIONS: These results indicate that NGF locally expressed in the bladder is an important mediator inducing bladder overactivity with upregulation of C-fiber afferent markers and downregulation of an A-type K(+) channel subunit in DRG following PI, and that liposome-based, local NGF-targeting therapy could be effective for not only bladder overactivity and afferent sensitization, but also PI. Thus, local blockade of NGF in the bladder could be a therapeutic modality for male LUTS due to BPH with PI.

AIMS Detrusor underactivity (DU) is an understudied health concern with inadequate clinical management. The pathophysiology of DU is unclear, and current therapies fail to improve symptoms. The current studies characterized voiding function and contractility of bladder and urethral tissues in a novel rat model of DU. METHODS Female obese prone (OP) and obese resistant (OR) rats were fed a 60 kcal% fat diet at 8 weeks old. A subset of rats (n = 4/strain) underwent uroflowmetry biweekly for 18 weeks in metabolic cages. At 40-56 weeks old, rats (n = 9-10/strain) underwent instrumented cystometry under urethane anesthesia. Following cystometry, bladder and urethral tissues (n = 8-9/strain) were harvested for in vitro assessments of contractility in response to carbachol, electric field stimulation, atropine, alpha, beta-methylene ATP, and caffeine. RESULTS OP rats exhibited increased urinary frequency (p = 0.0031), decreased voided volume (p = 0.0093), and urine flow rate (p = 0.0064) compared to OR rats during uroflowmetry. Bethanechol (10 mg/kg) did not alter uroflowmetry parameters. During cystometry, OP rats exhibited decreased bladder emptying efficiency (p

AIMS To compare in vivo differences of two catheter systems for urodynamics to further discover their measurement properties. METHODS Side-by-side catheterization with two catheters for intravesical and abdominal pressure during full cystometry in 36 prospectively recruited patients with analysis of mean and absolute differences at urodynamic events and post hoc in-depth signal analysis comparing the full pressure traces of both systems. RESULTS The mean pressure differences at urodynamic events between air-filled and water-filled systems are small, however, with a large variation, without a systematic difference. The majority of the intersystem differences are significantly larger than 5 cmH2 O. Further analysis showed that urodynamic event pressure differences of both systems at the start of the test were carried forward throughout the remainder of the test without subsequent or additional tendency to differ. Post hoc whole test signal analysis with pressures equalized from the first sample shows high cross-correlation (>0.981) between the pressure signals per location (rectum and bladder) per test and almost zero-time shift (

Objectives To investigate the effect of vibegron, a new clinically approved β3-adrenoceptor agonist in lower urinary tract dysfunction in mice with spinal cord injury. Methods Investigators performed cystometry under awake conditions in 4-week spinal cord injury female mice. Two weeks after spinal cord injury, saline or vibegron (30 mg/kg) was orally administered for 2 weeks prior to the urodynamic study. Investigators removed L6-S1 dorsal root ganglia from the saline- or vibegron-treated spinal cord injury mice as well as from saline-treated normal (spinal intact) mice to evaluate the levels of transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, activating transcription factor 3, and inducible nitric oxide synthase transcripts using real-time polymerase chain reaction. Results In vibegron-treated spinal cord injury mice, nonvoiding contractions during bladder filling, which were increased in spinal cord injury compared to spinal intact mice, were significantly decreased. Micturition pressure or voiding efficiency was not significantly increased in comparison to measurements in saline-treated spinal cord injury mice. The expression of transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, activating transcription factor 3, and inducible nitric oxide synthase messenger RNA was increased in spinal cord injury mice compared to spinal intact mice, but significantly decreased after vibegron treatment. Conclusions Vibegron improves spinal cord injury-induced detrusor overactivity in addition to significantly reducing C-fiber afferent receptors such as transient receptor potential cation channel subfamily V member 1, transient receptor potential cation channel subfamily A member 1, and inflammatory cytokines/markers, such as activating transcription factor 3 and inducible nitric oxide synthase, in spinal cord injury mice. Thus, vibegron might be effective in the treatment of storage lower urinary tract dysfunction induced by C-fiber afferent activation after spinal cord injury.

Aims Spinal cord injury (SCI) above the sacral level causes bladder dysfunction and remodeling with fibrosis. This study examined the antifibrotic effects using nintedanib, an inhibitor of vascular endothelial growth factor, fibroblast growth factor, and platelet-derived growth factor receptors, on detrusor overactivity (DO) and bladder fibrosis, as well as the modulation mechanisms of C-fiber afferent pathways. Methods Thirty female C57BL/6 mice were divided into group A (spinal intact), group B (SCI with vehicle), and group C (SCI with nintedanib). At 2 weeks after SCI, vehicle or 50 mg/kg nintedanib was administered subcutaneously for 2 weeks. Then, cystometry was conducted, followed by RT-PCR measurements of fibrosis-related molecules, muscarinic, β-adrenergic, TRP and purinergic receptors in the bladder or L6-S1 dorsal root ganglia (DRG). Trichrome stain and Western blot analysis of transforming growth factor-beta and fibronectin were performed in the bladder. TRPV1 expression in L6 DRG was measured by immunohistochemistry. Results In cystometry, intercontraction intervals, nonvoiding contractions, voided volume, and voiding efficiency were significantly improved in group C versus group B. RT-PCR, Western blotting, and trichrome staining revealed the fibrotic changes in the bladder of group B, which was improved in group C. Increased messenger RNA levels of TRPV1, TRPA1, P2X2 , and P2X3 in DRG of group B were significantly decreased in group C. TRPV1 immunoreactivity in DRG was increased in group B, but decreased in group C. Conclusions Nintedanib improves storage and voiding dysfunctions and bladder fibrosis in SCI mice. Also, nintedanib-induced improvement of DO is associated with reduced expression of C-fiber afferent markers, suggesting the modulation of bladder C-fiber afferent activity.

AIMS To investigate the relationship between lower urinary tract function and the accessory nerve (ACN) arising from the major pelvic ganglion (MPG). METHODS Ten-week-old male Wistar/ST rats were randomly divided into eight groups according to the type of treatment (sham or bilateral accessory nerve injury [BACNI]) and the duration of observation (3 days, 1 week, 2 weeks, or 4 weeks: Sham-3d, Sham-1w, Sham-2w, Sham-4w, BACNI-3d, BACNI-1w, BACNI-2ws, and BACNI-4w. BACNI was induced in the following manner: the ACN was crushed for 1 min (2 mm away from the MPG) using reverse-action tweezers. The same procedure was performed on both sides. On the last day of each observation period, the bladder function was measured by awake cystometry, and histological evaluation was performed. RESULTS All rats in the Sham groups micturated normally. In the BACNI-3d and BACNI-1w groups, all rats showed symptoms of overflow urinary incontinence (OUI). This OUI improved gradually over time. The bladder's size in the BACNI group was significantly larger than that in the Sham group (p

Background The aim of the present study was to investigate the effects of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) on bladder function and pathophysiology. Methods To create a model for CPPS, rats were intraprostatically injected with zymosan or saline, serving as control. Metabolic cage experiments were performed 7, 14, or 21 days after zymosan injection and after 14 days in the control group. Thereafter, cystometry was performed in which simulated micturition cycles were induced by saline infusion and contractile responses to the cholinergic agonist methacholine and the purinergic agonist ATP were measured. Following cystometry, the prostate and urinary bladder were excised and assessed histopathologically for possible inflammatory changes. Results Metabolic cage data revealed a significantly increased urinary frequency in zymosan treated rats. Likewise, the volume per micturition was significantly lower in all CPPS groups compared to controls. Cystometry showed a significant increase in the number of nonvoiding contractions, longer voiding time, and a trend towards lower compliance in CPPS rats compared to controls. Induction of CPPS led to significantly reduced cholinergic and purinergic contractile responses. Histopathological analysis demonstrated prostatic inflammation in all CPPS groups, in particular in later stage groups. Both the extent and grade of bladder inflammation were significantly higher in CPPS groups compared to controls. Conclusions The current findings demonstrate a potential prostate-to-bladder cross-sensitization leading to symptoms of bladder overactivity and signs of bladder inflammation. Future clinical studies are required to verify the outcomes of the current study and enable advancement of patient care.

Aims To investigate the effect of losartan on preventing bladder fibrosis and protecting renal function in rats with neurogenic paralysis bladder (NPB). Materials and methods Rats were assigned to the transecting spinal nerves group (TSNG), transecting spinal nerves + losartan group (LSTG), and control group (CG). On Day 32 postsurgery, bladder capacity (BC), bladder compliance (ΔC), bladder leakage pressure (Pves.leak) of TSNG and LSTG while BC, ΔC, and bladder threshold pressure (Pves.thre) of CG were measured by cystometry in each cohort. Renal function and the expression quantity of Angiotensin Ⅱ (Ang II) in blood were detected, in addition Ang II, Ang II Type 1 receptor (AT1), transformation growth factor β1 (TGFβ1), Collagen Ⅲ, and collagen fibrin in the bladder tissue were detected too. Results ΔC in TSNG and LSTG decreased significantly compared to the CG. Pves.leak in TSNG and LSTG were significantly higher than Pves.thre in CG. Renal function of both TSNG and LSTG decreased significantly compared with the CG, but renal function in LSTG was better than in TSNG. Ang Ⅱ in blood and bladder tissue in TSNG and LSTG increased significantly compared with CG. AT1 was expressed in the bladder tissue of all rats. The TGFβ1, Collagen Ⅲ, and collagen fibrin expression level increased significantly in TSNG compared with LSTG and CG, while these levels were not significantly different between CG and LSTG. Conclusion Losartan might prevent NPB fibrosis by stopping the upregulated signaling of Ang II/AT1/TGFβ1 and consequently may reduce kidney damage from occurring.

Objective To study the role of transient receptor potential melastatin 2 in bladder function and inflammation-associated hypersensitivity. Methods We evaluated physiological function of the bladder and intravesical lipopolysaccharide-induced inflammatory nociceptive responses in female wild-type and transient receptor potential melastatin 2-knockout mice. In vivo frequency/volume and decerebrated unanesthetized cystometry measurements, as well as in vitro detrusor strip functional studies, were carried out to evaluate bladder function. Mice received intravesical lipopolysaccharide (2.0 mg/mL) or saline instillation to evaluate responses to bladder inflammation. Voiding and bladder pain-like behaviors, cystometry measurements and histological evaluation were carried out before and after intravesical lipopolysaccharide instillation. Results Few phenotypic differences in in vivo and in vitro physiological function were found between the two genotypes. Comparison of measurements taken before and 24-48 h after intravesical lipopolysaccharide instillation showed that voiding parameters did not change in transient receptor potential melastatin 2-knockout mice, whereas an increased voiding frequency was observed in wild-type mice. At 24 h after intravesical lipopolysaccharide instillation, the numbers of bladder pain-like behaviors and of infiltrated inflammatory cells in the bladder submucosal layer were significantly increased, and the voided volume and the intercontraction interval were significantly decreased on cystometry measurements in wild-type mice compared with those in both transient receptor potential melastatin 2-knockout mice and in wild-type mice treated with saline instillation. Conclusions Although the physiological roles of transient receptor potential melastatin 2 channels in the bladder might be limited, inflammation and associated hypersensitivity of the bladder caused by intravesical lipopolysaccharide instillation are attenuated in transient receptor potential melastatin 2-knockout mice, suggesting pathophysiological roles of transient receptor potential melastatin 2 channels in these processes.

BACKGROUND Dutasteride administration reportedly improves lower urinary tract symptoms in patient with chronic, histologically-identified prostatic inflammation, potentially through estrogen receptor β (ERβ), activation of which has anti-inflammatory effects in the prostate tissue. Therefore, we investigated the effect of dutasteride on intraprostatic inflammatory responses and bladder activity using a rat model of chemically induced prostatic inflammation. METHODS Male Sprague-Dawley rats at 10 weeks old were used. Prostatic inflammation was induced by 5% formalin injection into ventral lobes of the prostate and saline was injected in the control group (control, n = 5). Rats with prostatic inflammation were divided into dutasteride therapy (dutasteride, n = 5) and placebo groups (placebo, n = 5). Dutasteride was administrated at a dose of 0.5 mg/kg daily from 2 days before induction of prostatic inflammation whereas placebo rats received vehicle only. Twenty-eight days later, cystometry was performed in a conscious condition to measure non-voiding contractions (NVCs), intercontraction intervals (ICI) and postvoid residual volume (RV). After cystometry, the prostate was excised for analysis of messenger RNA (mRNA) expression levels of ERα, ERβ, interleukin-1β (IL-1β), and IL-18 by quantitative polymerase chain reaction. RESULTS The mean number of NVCs was significantly greater in placebo group than that of control group without prostatic inflammation (p

Storage and voiding of urine from the lower urinary tract (LUT) must be timed precisely to occur in appropriate behavioral contexts. A major part of the CNS circuit that coordinates this activity is found in the lumbosacral spinal cord. Immediate early gene (IEG) activity mapping has been widely used to investigate the lumbosacral LUT‐related circuit, but most reports focus on the effects of noxious stimulation in anesthetized female rats. Here we use c‐Fos and EGR‐1 (Zif268) activity mapping of lumbosacral spinal cord to investigate cystometry‐induced micturition in awake female and male rats. In females, after cystometry c‐Fos neurons in spinal cord segments L5–S2 were concentrated in the sacral parasympathetic nucleus (SPN), dorsal horn laminae II–IV, and dorsal commissural nucleus (SDCom). Comparisons of cystometry and control groups in male and female revealed sex differences. Activity mapping suggested dorsal horn laminae II–IV was activated in females but showed net inhibition in males. However, inhibition in male rats was not detected by EGR‐1 activity mapping, which showed low coexpression with c‐Fos. A class of catecholamine neurons in SPN and SDCom neurons were also more strongly activated by micturition in females. In both sexes, most c‐Fos neurons were identified as excitatory by their absence of Pax2 expression. In conclusion, IEG mapping in awake male and female rats has extended our understanding of the functional molecular anatomy of the LUT‐related circuit in spinal cord. Using this approach, we have identified sex differences that were not detected by previous studies in anesthetized rats., A major part of the circuit that coordinates bladder voiding is found in the lumbosacral spinal cord. Here we use c‐Fos and EGR‐1 (Zif268) activity mapping of lumbosacral spinal cord to investigate cystometry‐induced micturition in awake female and male rats. In both sexes, most c‐Fos neurons were identified as excitatory by their absence of Pax2 expression. Using this approach, we have identified sex differences that were not detected by previous studies in anesthetized rats.

Aims: Rodent cystometry has provided valuable insights into the impact of the disease, injury, and aging on the cellular and molecular pathways, neurologic processes, and biomechanics of lower urinary tract function. The purpose of this white paper is to highlight the benefits and shortcomings of different experimental methods and strategies and to provide guidance on the proper interpretation of results. Methods: Literature search, selection of articles, and conclusions based on discussions among a panel of workers in the field. Results: A range of cystometric tests and techniques used to explore biological phenomena relevant to the lower urinary tract are described, the advantages and disadvantages of various experimental conditions are discussed, and guidance on the practical aspects of experimental execution and proper interpretation of results are provided. Conclusions: Cystometric evaluation of rodents comprises an extensive collection of functional tests that can be performed under a variety of experimental conditions. Decisions regarding which approaches to choose should be determined by the specific questions to be addressed and implementation of the test should follow standardized procedures. (Less)

Objectives To report the effect of a selective androgen receptor modulators (SARMs) on the urethral continence mechanisms in a rat model of stress urinary incontinence (SUI) induced by bilateral ovariectomy (OVX). Materials and methods Female Sprague-Dawley rats with bilateral OVX were used. Rats were divided into five groups; sham operated, vehicle-treated OVX, low-dose SARM-treated OVX (GSK2849466A: 0.005 mg/kg/day, per os [p.o.]), high-dose SARM-treated OVX (GSK2849466A: 0.03 mg/kg/day, p.o.) and dihydrotestosterone (DHT)-treated OVX (1 mg/kg/day, subcutaneous) groups. After 4 weeks of SARM treatments or 3 weeks of DHT treatment (6 weeks after OVX), rats were subjected to evaluation of the sneeze-induced continence reflex using microtransducer-tipped catheter methods, sneeze-induced leak-point pressure, and continuous cystometry measurements, followed by histological analyses of urethral tissues. Results (i) OVX significantly impaired urethral continence function after 6 weeks to induce SUI during sneezing. (ii) Low-dose SARM treatment restored urethral baseline pressure (UBP) without affecting the amplitude of urethral response during sneezing (A-URS), partially reversing OVX-induced SUI during sneezing. (iii) High-dose SARM treatment reversed decreases in both UBP and A-URS, more effectively preventing SUI during sneezing. (iv) DHT treatment only restored A-URS without affecting UBP, partially preventing OVX-induced SUI during sneezing. (v) The high-dose SARM treatment induced hypertrophy of the striated and smooth muscle around the urethra. (vi) SARM treatment did not affect bladder function in sham or OVX rats. Conclusion Treatment with SARMs could be a more effective modality for the treatment of SUI than DHT, without affecting bladder function, by enhancing smooth- and striated muscle-mediated urethral function under stress conditions such as sneezing.

INTRODUCTION Urological chronic pelvic pain syndrome (UCPPS) represents a group of pain symptoms relating to patients with pelvic pain for which treatment is largely unsatisfactory. The objective of this study is to analyze the effects of a novel treatment strategy in males suffering from UCPPS. METHODS This retrospective, institutional review board-approved study analyzed eight male patients aged 24 to 61 with UCPPS. All the patients had a trial of antibiotic therapy, NSAIDs, and pelvic floor physical therapy before the study. The Visual Analog scale (VAS) and Functional Pelvic Pain scale (FPPS) were collected pretreatment. While continuing physical therapy, patients underwent weekly ultrasound-guided pelvic floor trigger point injections to the iliococcygeus, pubococcygeus, and puborectalis with lidocaine 1%. Concomitantly, patients received peripheral nerve hydrodissection performed on the pudendal nerve and the posterior femoral cutaneous nerve. The first two injections combined 1% lidocaine with dexamethasone, while the next four injections consisted of 1% lidocaine with traumeel (a homeopathic, plant-derived anti-inflammatory medication). At the 6-week follow-up, each patient retook the VAS and FPPS. RESULTS The mean age of our patients was 31.8 years and the average duration of symptoms of the UCPPS was 21 months. Pretreatment, the mean VAS was 3.3 (STD 1.7) and the mean VAS posttreatment was 1.8 (STD 1.4); P

Aim To investigate the role of p38 MAP kinase in lower urinary tract dysfunction in mice with spinal cord injury (SCI). Methods Cystometry and external urethral sphincter-electromyography were performed under an awake condition in 4-week SCI female mice. Two weeks after SCI, a catheter connected to an osmotic pump filled with a p38 mitogen-activated protein kinase (MAPK) inhibitor or artificial cerebrospinal fluid (CSF) was implanted into the intrathecal space of L6-S1 spinal cord for continuous intrathecal instillation at infusion rate of 0.51 μL/h for 2 weeks before the urodynamic study. L6 dorsal root ganglia were then removed from CSF and p38 MAPK inhibitor-treated SCI mice as well as from CSF-treated normal (spinal intact) mice to evaluate the levels of transient receptor potential cation channel subfamily V member 1 (TRPV1), tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS) transcripts by real-time polymerase chain reaction. Results In p38 MAPK inhibitor-treated SCI mice, nonvoiding contractions during bladder filling, bladder capacity, and post-void residual volume were significantly reduced while micturition pressure and voiding efficiency were significantly increased in comparison to these measurements in CSF-treated SCI mice. The expression of TRPV1, TNF-α, and iNOS messenger RNA was increased in SCI mice compared with expression in spinal intact mice and significantly decreased after p38 MAPK inhibitor treatment. Conclusions The p38 MAPK signaling pathway in bladder sensory neurons or in the spinal cord plays an important role in storage and voiding problems such as detrusor overactivity and inefficient voiding after SCI.

Aim We investigated the effects of Ba-Wei-Die-Huang-Wan (BWDHW) on ketamine-induced cystitis (KIC) in a rat model. Methods Female Sprague-Dawley rats were distributed into three groups: control (saline), ketamine (25 mg/kg/day for 28 days), or ketamine (25 mg/kg/day for 28 days) plus BWDHW (90 mg/kg/day, started from day 14). Functional magnetic resonance imaging (fMRI), metabolic cage study, and cystometry were evaluated. Bladder histology was evaluated. Western blots of the bladder proteins were carried out. Results Compared with controls, ketamine-treated rats showed stronger fMRI intensity in the periaqueductal gray area and bladder overactivity in the bladder functional study, but the ketamine/BWDHW-treated rats did not. Furthermore, ketamine breached the uroplakin III membrane at the apical surface of the urothelium, enhanced substance P spread over the urothelium, induced suburothelial hemorrhage and monocyte/macrophage infiltration, and caused interstitial fibrosis deposition. By contrast, the BWDHW-treated rats exhibited less substance P spread, lower suburothelial monocyte/macrophage infiltration, and lower interstitial fibrosis deposition. The ketamine group showed significant overexpression of neuroreceptors in the bladder mucosa (the transient receptor potential vanilloid 1 and M2 - and M3 -muscarinic receptors) and detrusor (M2 - and M3 -muscarinic receptors); inflammatory mediators in the detrusor (interleukin-1β [IL-1β], IL-6, tumor necrosis factor-α, nuclear factor-κB, cyclooxygenase-2, and intercellular adhesion molecule-1); and fibrogenesis molecules in the detrusor (transforming growth factor-β1, collagen I, collagen III, and fibronectin). However, no significant changes were noted between the ketamine/BWDHW and control groups. Conclusion BWDHW could exert therapeutic effects by inhibiting the upregulation of neuroreceptors, modulating inflammatory mediators, suppressing fibrogenesis, and ameliorating bladder overactivity in rats with KIC.

AIM Obesity is a strong independent risk factor for urinary incontinence. Effective therapeutic approaches for obesity-associated stress urinary incontinence (OA-SUI) are lacking as the mechanisms remain unclear. The aim of our study is to explore the impacts of microenergy acoustic pulse (MAP) therapy on urethral and pelvic floor muscle structure and function in female lean and fatty rats. METHODS A total 24 Zucker fatty (ZF) and 24 Zucker lean (ZL) female 24-week-old rats were grouped into four groups: ZL control, ZLMAP, ZF control, and ZFMAP. For MAP treatment, 500 pulses were delivered at an energy level of 0.033 mJ/mm 2 and a frequency of 3 Hz and were applied twice a week for 4 weeks. After a 1-week washout, all rats underwent conscious cystometry and leak-point pressure (LPP) measurements followed by ex vivo organ-bath assay and histological study. RESULTS ZF rats had lower LPP as compared to ZL rats, and MAP treatment significantly improved LPP in ZF rats (P

Aims The goal of this study was to test whether central corticotropin-releasing factor (CRF) was involved in angiotensin II (Ang II) and Ang II type 1 (AT1) receptor-mediated facilitation of micturition reflex and to investigate whether peripherally administered telmisartan, AT1 receptor antagonist, suppresses the central Ang II-induced facilitation of micturition reflex in rats. Methods Urethane anesthetized male Wistar rats were placed under continuous cystometry before and after intracerebroventricular administration of each drug. Rats were intracerebroventricularly administered telmisartan (AT1 receptor antagonist), CP154526 (CRF1 receptor antagonist), or K41498 (CRF2 receptor antagonist) 30 minutes before intracerebroventricular administration of Ang II. Some male Wistar rats were perorally pretreated with either vehicle, AT1 receptor antagonist telmisartan or valsartan, once daily for 8 days, then measured blood pressure. Thereafter, Ang II was intracerebroventricularly administered for continuous cystometry. Results Intracerebroventricularly administered telmisartan or CP154526 dose-dependently suppressed the central Ang II-induced intercontraction interval (ICI) reduction. In contrast, intracerebroventricularly administered K41498 did not affect the central Ang II-induced response compared to vehicle pretreatment. Peripherally administered telmisartan but not valsartan suppressed the central Ang II-induced ICI reduction in rats compared to vehicle administration without altering blood pressure. Conclusions Central Ang II induced facilitation of the micturition reflex through AT1 and CRF1 receptors. Peripherally administered telmisartan suppressed central Ang II-induced facilitation of micturition reflex.

Aims To further explore the effects of a novel EP2 and EP3 dual agonist, ONO-8055, on detrusor contractility, we investigated the responses of bladder strips from sham and lumbar canal stenosis (LCS) rats to this agonist, its effects on lower urinary tract function in normal rats, and mRNA expression of EP2 and EP3 receptors in the sham and LCS rats. Methods The responses of bladder strips from sham and LCS rats to ONO-8055 were measured. The effects of ONO-8055 on LUT function of normal rats were investigated with awake cystometry and intraurethral perfusion pressure (Pura) measurements. The relative mRNA of bladder and urethral tissue of the sham and LCS rats was quantified using specific probes for EP1, EP2, EP3, and EP4 genes. Results Compared with the vehicle, the muscle tensions of both the sham and LCS rats were significantly increased after adding this agonist. On awake cystometry of normal rats, bladder capacity and Pura were decreased in the ONO-8055 groups, but a statistically significant difference in mean changes was demonstrated only between the vehicle group and the group receiving the highest dose. Compared with the sham rats, mRNA expressions of the four EP receptors in the lower urinary tract of the LCS rats did not show a statistically significant difference. Conclusions This agonist did not augment bladder contractility or urethral relaxation in normal rats.

Objectives To elucidate the mechanism of action of the α1 -blocker, naftopidil, in partial bladder outlet obstruction animals, by studying non-voiding contractions, and the levels of mediators were measured with resiniferatoxin treatment. Methods A total of 35 female Wistar rats were randomly divided into a sham or bladder outlet obstruction group, and rats in each group were given vehicle or resiniferatoxin. Incomplete urethral ligation was applied to the bladder outlet obstruction group. After cystometry, the intravesical level of prostaglandin E2 and adenosine 5'-triphosphate was measured in the instilled perfusate collected. Naftopidil was given at the time of cystometry. Results In bladder outlet obstruction rats, non-voiding contractions, bladder capacity, and the intravesical levels of prostaglandin E2 and adenosine 5'-triphosphate were markedly increased compared with sham rats. Naftopidil decreased non-voiding contractions, enlarged the bladder capacity, and decreased the intravesical levels of prostaglandin E2 and adenosine 5'-triphosphate. Resiniferatoxin enhanced non-voiding contractions. The effects of naftopidil on non-voiding contractions and the intravesical level of prostaglandin E2 , but not adenosine 5'-triphosphate, were tolerant to resiniferatoxin. Conclusions In bladder outlet obstruction rats, one cause of generation of non-voiding contractions might be bladder wall distension, but not transient receptor potential cation channel V1. The increase in intravesical prostaglandin E2 might also be associated with the generation of non-voiding contractions. Naftopidil inhibits the increase in non-voiding contractions and decreases the intravesical level of prostaglandin E2 , which are independent of transient receptor potential cation channel V1.

Aim Diabetic bladder dysfunction (DBD) is one of the most common and bothersome complications of diabetes mellitus (DM). This study aimed to investigate the functional, structural, and molecular changes of the bladder at 0, 3, 6, 9, and 12 weeks after DM induction by streptozotocin (STZ) in male C57BL/6 mice. Methods Male C57BL/6J mice were injected with STZ (130 mg/kg). Then, diabetic general characteristics, cystometry test, histomorphometry, and contractile responses to α, β‐methylene ATP, KCl, electrical‐field stimulation, carbachol were performed at 0, 3, 6, 9, and 12 weeks after induction. Finally, protein and messenger RNA (mRNA) expressions of myosin Va and SLC17A9 were quantified. Results DM mice exhibited lower body weight, voiding efficiency and higher water intake, urine production, fasting blood glucose, oral glucose tolerance test, bladder wall thickness, maximum bladder capacity, residual volume, bladder compliance. In particular, nonvoiding contractions has increased more than five times at 6 weeks. And the amplitudes of spontaneous activity, contractile responses to all stimulus was about two times higher at 6 weeks but cut almost in half at 12 weeks. The protein and mRNA expressions of myosin Va and SLC17A9 were about two times higher at 6 weeks, but myosin Va was reverted nearly 40% while SLC17A9 is still higher at 12 weeks. Conclusions DBD transitioned from a compensated state to a decompensated state in STZ‐induced DM mice at 9 to 12 weeks after DM induction. Our molecular data suggest that the transition may be closely related to the alterations of myosin Va and SLC17A9 expression levels in the bladder with time.

KEY POINTS: There is clinical evidence showing that prostatic inflammation contributes to overactive bladder symptoms in male patients; however, little is known about the underlying mechanisms. In this study, we investigated the mechanism that prostatic inflammation causes detrusor overactivity by using a rat model of chemically induced prostatic inflammation. We observed a significant number of dorsal root ganglion neurons with dichotomized afferents innervating both prostate and bladder. We also found that prostatic inflammation induces bladder overactivity and urothelial NGF overexpression in the bladder, both dependent on activation of the pelvic nerve, as well as changes in ion channel expression and hyperexcitability of bladder afferent neurons. These results indicate that the prostate‐to‐bladder cross‐sensitization through primary afferent pathways in the pelvic nerve, which contain dichotomized afferents, could be an important mechanism contributing to bladder overactivity and afferent hyperexcitability induced by prostatic inflammation. ABSTRACT: Prostatic inflammation is reportedly an important factor inducing lower urinary tract symptoms (LUTS) including urinary frequency, urgency and incontinence in patients with benign prostatic hyperplasia (BPH). However, the underlying mechanisms inducing bladder dysfunction after prostatic inflammation are not well clarified. We therefore investigated the effects of prostatic inflammation on bladder activity and afferent function using a rat model of non‐bacterial prostatic inflammation. We demonstrated that bladder overactivity, evident as decreased voided volume and shorter intercontraction intervals in cystometry, was observed in rats with prostatic inflammation versus controls. Tissue inflammation, evident as increased myeloperoxidase activity, and IL‐1α, IL‐1β, and IL‐6 levels inside the prostate, but not in the bladder, following intraprostatic formalin injection induced an increase in NGF expression in the bladder urothelium, which depended on activation of the pelvic nerve. A significant proportion (18–19%) of dorsal root ganglion neurons were double labelled by dye tracers injected into either bladder or prostate. In rats with prostatic inflammation, TRPV1, TRPA1 and P2X2 increased, and Kv1.4, a potassium channel α‐subunit that can form A‐type potassium (K(A)) channels, decreased at mRNA levels in bladder afferent and double‐labelled neurons vs. non‐labelled neurons, and slow K(A) current density decreased in association with hyperexcitability of these neurons. Collectively, non‐bacterial inflammation localized in the prostate induces bladder overactivity and enhances bladder afferent function. Thus, prostate‐to‐bladder afferent cross‐sensitization through primary afferents in the pelvic nerve, which contain dichotomized afferents, could underlie storage LUTS in symptomatic BPH with prostatic inflammation.

Aims The main goal of our study was to investigate whether blebbistatin would prevent the cyclophosphamide (CYP)-induced changes in cystometric and inflammatory parameters indicating the development of bladder inflammation and bladder overactivity. As the nature of CYP-induced urotoxicity is inflammatory, we assume that agents presenting an anti-inflammatory potential, such as blebbistatin, are worth special attention. Materials and methods The experiments were carried out in female Wistar rats. Surgical procedures, cystometric investigations, measurements of bladder edema and urothelium thickness as well as biochemical analyses were performed according to the published literature. Results As expected, an acute administration of CYP (200 mg/kg, intraperitoneally) induced changes in the cystometric parameters and the levels of the tested biomarkers (ie, interleukin 1-β, interleukin 6, interleukin 10, tumor necrosis factor-α, nerve growth factor, brain-derived neurotrophic factor, heparin-binding epidermal growth factor-like growth factor, insulin-like growth factor-binding protein 3, C-X-C motif chemokine 10, orosomucoid-1, Tamm-Horsfall protein, hemopexin, and occludin), indicating the development of bladder overactivity and bladder inflammation, respectively. These changes were accompanied by bladder edema and increased urothelium thickness. Intravesical infusion of blebbistatin for 7 days (125 nmol/day) prevented all symptoms of the CYP-induced urotoxicity. Conclusions Blebbistatin might be a promising novel agent for the treatment of bladder dysfunctions, like CYP-induced hemorrhage cystitis or bladder overactivity, since it diminished the increased urinary bladder levels of proinflammatory markers and normalized the concentrations of the anti-inflammatory ones. This effect was accompanied by amelioration of bladder edema and permeability, and normalization of both urothelium thickness and values of the cystometric parameters.

We investigated the effects of sacral neuromodulation using the new six-contact electrode vs the four-contact electrode in pigs.Randomly, a six-contact electrode was implanted in eight pigs in one side of the third sacral (S3) foramen, and a four-contact electrode was implanted in the other side using the same method. Using an external neurostimulator, the number of contact points (sensitive voltage ≤ 2 V) of both electrodes (SacralStim and InterStim systems) was calculated. Cystometry was performed by infusing normal saline or acetic acid. Then sacral neuromodulation with the SacralStim and InterStim systems was induced at a voltage at which we could observe perianal and/or tail movement. Multiple cystometrograms were performed to determine the effects of the two systems on the micturition reflex.The mean number of sensitive points of six-contact electrodes of the SacralStim system (2.63 ± 0.32) was higher than that of the quadripolar-lead electrodes of the InterStim system (1.38 ± 0.18), and the difference was statistically significant (P 0.05). Acetic acid-induced bladder overactivity significantly reduced bladder capacity to 54.89% ± 4.7% of the normal saline control level. During acetic acid infusion, sacral neuromodulation with the SacralStim system suppressed bladder overactivity and significantly increased bladder capacity to 70.41% ± 5.4% of the normal saline control level, compared with the acetic acid level ( P 0.05). Moreover, sacral neuromodulation with the InterStim system also significantly increased bladder capacity to 69.63% ± 5.3% of the normal saline control level, compared with the acetic acid level ( P 0.05). No significant differences were found in the results obtained using the two systems ( P 0.05).The six-contact electrode of the SacralStim system had more sensitive points (2 V) than that of the quadripolar-lead electrode of InterStim system. Potentially, it has more postimplantation programming options and battery savings manifested by lower voltage will increase the longevity of the stimulator. Further studies of sacral neuromodulation with six-contact electrodes in clinical practice are needed.

OBJECTIVES To examine the effects of tadalafil on bladder function and object recognition ability in rats with alterations in urinary frequency and locomotor activity as a result of pelvic venous congestion. METHODS A total of 48 female rats were divided into three groups (sham, pelvic venous congestion and pelvic venous congestion/tadalafil groups). In the pelvic venous congestion and pelvic venous congestion/tadalafil groups, the bilateral common iliac veins and uterine veins were ligated under anesthesia. Rats in the pelvic venous congestion/tadalafil group received a diet containing tadalafil, and the other rats were fed a normal diet. After 4 weeks, rats underwent analysis of voiding behavior, locomotor activity, a novel object recognition test, continuous cystometry, measurement of plasma monoamines, and measurement of plasma and urinary nitric oxide metabolites. Expression of nitric oxide synthase messenger ribonucleic acid in the bladder wall was also assessed, along with histological examination of the bladder. RESULTS Rats with pelvic venous congestion showed a higher urinary frequency, lower locomotor activity, and lower plasma and urinary nitric oxide levels than sham rats. The bladder wall endothelial nitric oxide synthase messenger ribonucleic acid level was low and object recognition was impaired. Pelvic venous congestion/tadalafil rats showed improvement in locomotor activity, bladder function and object recognition compared with pelvic venous congestion rats, as well as elevation of plasma and urinary nitric oxide, plasma monoamines, and bladder neuronal nitric oxide synthase messenger ribonucleic acid expression. Bladder wall vascularity was greater in pelvic venous congestion/tadalafil rats compared with sham rats. CONCLUSIONS In rats with pelvic venous congestion, tadalafil might improve bladder function and the general condition by increasing blood flow to the bladder and brain, and by increasing dopamine levels.

OBJECTIVES: To create a rat model for neurogenic detrusor underactivity (DU) by bilateral pelvic nerve crush injury (BPNI) and to study temporal changes in detrusor contractility and morphology. METHODS: Male Sprague-Dawley rats were subjected to BPNI or sham surgery and evaluated 1, 3 and 9 weeks after surgery. Bladder function was determined in vivo by awake cystometry, micturition pattern analysis and 24-hours urine collection. Bladders were harvested for in vitro pharmacological investigation by isometric tension recording. Bladders and major pelvic ganglia were investigated by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and histochemistry. RESULTS: Overflow incontinence was observed 1 week after BPNI. At 3 and 9 weeks after BPNI, rats showed a bladder phenotype characteristic for DU with increased post-void residuals, reduced voiding efficiencies and lower maximum pressures. In isolated bladder strips, contractile responses to potassium chloride (KCl), carbachol and α,β-methylene adenosine 5'-triphosphate (α,β-mATP) were preserved. On the other hand, neural induced contractility was reduced after BPNI, in line with reduced expression of protein gene product 9.5 and choline acetyltransferase in the major pelvic ganglion 1 week after BPNI. Bladder-to-body weight ratio and detrusor thickness increased following BPNI, indicating detrusor hypertrophy to compensate for the reduced neural input. CONCLUSIONS: BPNI induces a rat model for neurogenic DU. In this model, the detrusor maintains its contractility but denervation of the detrusor was observed. This article is protected by copyright. All rights reserved. ispartof: BJU Int vol:123 issue:5A pages:E86-E96 ispartof: location:England status: Published online

Introduction: in severe post prostatectomy stress urinary incontinence (SUI), urodynamics may not identify crucial parameters because of inadequate bladder filling. This study describes evaluation of cystometry and pressure flow study (PFS) in men where severe SUI during attempted filling necessitated application of a penile clamp to allow filling to reach cystometric capacity. Methods: we identified all men who had undergone prior radical prostatectomy from a database of patients attending for videourodynamic testing between 2012-2017. Symptom scores, bladder diary and free flow rate tests were retrieved. We evaluated the measurements of the subgroup of men with severe SUI for whom a Thomson-Walker compression clamp was utilised to enable full urodynamic evaluation. Results: 166 radical prostatectomy patients were identified. In 30 (18%), severe SUI led to incomplete filling cystometry, i.e. failure to reach cystometric capacity. Following application of the penile compression clamp, it was possible to achieve further filling in each case. Applying the clamp did not alter vesical filling or impede pressure recording. These men had a lower maximum urethral closure pressure (31.6 vs 46.5cmH2O; p

Author(s): Chang, Huiyi H; Yeh, Jih-Chao; Mao, Jackie; Ginsberg, David A; Ghoniem, Gamal; Rodriguez, Larissa V | Abstract: AimInterstitial cystitis/painful bladder syndrome/(IC/PBS) results in recurring pain in the bladder and surrounding pelvic region caused by abnormal excitability of micturition reflexes. Spinal cord stimulation (SCS) is currently clinically used for the attenuation of neuropathic and visceral pain. The present study examined whether SCS at upper lumbar segments modulates detrusor overactivity and visceral hyperalgesia associated with cystitis in a rat model of cyclophosphamide (CYP)-induced cystitis.MethodsCystitis was induced by intraperitoneal injection of CYP (200 mg/kg) in six adult female Sprague Dawley rats 48 h prior to urodynamic recordings. Another six rats served as-controls with saline injection. Cystometry and the external urethral sphincter (EUS) electromyography during bladder infusion were evaluated under urethane anesthesia. The visceromotor reflexes (VMR) obtained from the external abdominal oblique muscle were quantified during bladder infusion and isotonic bladder distension (IBD), respectively. After baseline recordings were taken, SCS was applied on the dorsal surface of L3 for 25 min. Urodynamic recordings and VMR during bladder infusion and IBD were repeated 2 h after SCS.ResultsCYP resulted in detrusor overactivity, stronger EUS tonic contractions, and increased VMR. SCS significantly reduced non-voiding contractions, prolonged EUS relaxation, and delayed VMR appearance during bladder infusion as well as significantly decreased VMR during IBD in cystitis rats.ConclusionSCS improved bladder function and EUS relaxation during bladder infusion and significantly attenuated visceral nociceptive-related VMR during IBD in cystitis rats. SCS may have therapeutic potential for patients with hyperalgesia and IC/PBS.

AIMS Interstitial cystitis and bladder pain syndrome is a prevalent health concern with inadequate treatments. Neuromodulation has emerged as a therapeutic option to treat patients refractory to standard care. The objective of this study was to determine the efficacy and mechanism(s) of sensory pudendal nerve stimulation on bladder function in cystitis rats. METHODS Female rats were administered saline (n = 8) or cyclophosphamide (CYP, 150 mg/kg IP, n = 16) and single-trial cystometry experiments were conducted under urethane anesthesia 48 h after injection. Electrical stimulation (0.02-0.22 mA, 10-20 Hz) was delivered to the sensory branch of the pudendal nerve and its effect on the bladder and external urethral sphincter were measured. Stimulation trials were also conducted following bilateral hypogastric nerve transection (HGNT) or pharmacological inhibition of beta-adrenergic receptors (propranolol, 1 mg/kg IV) to determine the mechanisms of bladder inhibition. RESULTS CYP-induced cystitis decreased bladder capacity (P = 0.0352) and bladder compliance (P = 0.024) by up to 38% of control. Electrical stimulation of the sensory pudendal nerve increased bladder capacity (P

To confirm changes in urethral activity with age, both intravesical pressure and urethral perfusion pressure (UPP) were recorded and external urethral sphincter electromyography (EUS‐EMG) was performed. A total of 33 female Sprague Dawley rats aged 3 months (young rats), 12 months (middle‐aged rats), and 24 months (aged rats) were used. Bladder activity was evaluated using continuous cystometry. Urethral activity was evaluated by simultaneously recording intravesical pressure and UPP in isovolumetric conditions under urethane anesthesia in each group. Additionally, EUS‐EMG activity was monitored under the same conditions. In continuous cystometry, the amplitude of bladder contractions was not different among the three groups; nevertheless, residual urine volume was significantly increased in middle‐aged and aged rats, as compared in young rats. With respect to UPP, the change in UPP was significantly smaller in aged rats (60%) and middle‐aged rats (64%) than in young rats. Furthermore, the mean amplitude of high‐frequency oscillations of the EUS was significantly lower in aged (61%) and middle‐aged rats (70%) than in young rats. EUS‐EMG revealed EUS bursting activity during voiding with clear active and silent phases in young rats but unclear active and silent phases in aged rats. Masson's trichrome staining of the urethra showed EUS atrophy in aged rats compared to young and middle‐aged rats. The results indicate that aging induces two urethral dysfunctions in the urethral smooth muscle and EUS, which may lead to dyscoordination between the urinary bladder and urethra., To confirm changes in urethral activity with age, both intravesical pressure and urethral perfusion pressure (UPP) were recorded and external urethral sphincter electromyography (EUS‐EMG) was performed. The amplitude of bladder contractions was not different among young, middle‐aged, and aged rats; nevertheless, residual urine volume was significantly increased in middle‐aged and aged rats and the change in UPP was significantly smaller in aged rats. In histological findings, EUS hypotrophy was observed in aged rats. The results indicate that aging induces two urethral dysfunctions in the urethral smooth muscle and EUS, which may lead to dyscoordination between the urinary bladder and urethra.

Although interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition causing bladder pain and urinary symptoms, effective treatments have not been established. The aim of this study was to adapt a chronic cystitis model in rats using lipopolysaccharide (LPS), which reflects IC/BPS pathology, and characterize the model's histological and behavioral effects. Furthermore, we investigated the effect of an α2δ subunit ligand, gabapentin (GBP), on bladder hypersensitivity of rats with chronic cystitis. Cystitis models were created by repeated intravesical injections of LPS. In the histological examination, the LPS‐injected group had greater inflammatory response, fibrosis, and abnormally thick re‐epithelialization. In the LPS‐injected group, LPS prompted hyperalgesia in both the lower abdomen and hind paw regions after day 1 of the first injection compared with the saline‐injected controls, without any recovery for 21 days at least. During cystometry, the LPS‐injected group showed bladder hyperactivity at all times. Systemic administration of GBP reduced cystitis‐related pain due to chronic inflammation and reduced the increased frequency of voiding in the LPS‐injected group. These results suggest that repeated intravesical injections of LPS induce long‐lasting bladder inflammation, pain, and overactivity in rats, while GBP is effective in the management of those symptoms in this chronic cystitis model. The current study identifies a relatively simple method to develop an animal model for chronic cystitis and provides evidence that GBP may be an effective treatment option for patients with IC/BPS., This study shows the repeated intravesical injections of lipopolysaccharide (LPS) could be used to generate a model of chronic cystitis in rats, which show signs of long‐lasting bladder inflammation, pain, and overactivity. Gabapentin, a neuromodulator, effectively inhibited bladder pain and overactivity in the LPS‐induced chronic cystitis rats.

Aims: To introduce the standard procedure of cystometry and interpretation of the results in children. Methods: The literature on cystometry in children in PubMed for the last 20 years was reviewed. The updated knowledge regarding indication, preparation, technique, and interpretation of cystometry in children were summarized. Results: Filling cystometry is the core content of a paediatric urodynamic study. In this section, the technique for performing cystometry is introduced in details. Emphasis is placed on correctly setting up the equipment according to ICS and ICCS guidelines, using appropriate terminology, providing indications for its performance with specific considerations for children, and proper interpretation of results. Conclusions: Cystometry can be used in children including newborn to evaluate lower urinary tract dysfunction.

Objectives To examine the effect of intrathecal (i.t.) serotonin (5-hydroxytryptamine) 5-HT7 agonist administration on voiding function in the urethane-anesthetised rat, and the change in 5-HT7 receptor (5-HT7 R) expression in the lumbosacral cord Onuf's nucleus after spinal cord injury (SCI). Materials and methods In all, 32 female Sprague-Dawley (SD) rats were equally divided into a spinally intact (SI) group and SCI group (n = 16 each). At 8 weeks after transection, half of the rats underwent continuous cystometry under urethane anaesthesia, and the 5-HT7 R-selective agonist LP44 was given (i.t.). The remaining rats were used for pseudorabies (PRV) retrograde tracing, immunofluorescence, and Western Blot. Results LP44 administered i.t. had no effect in the SI rats. In SCI rats, LP44 (1-30 μg/kg) induced significant dose-dependent increases in micturition volume, voiding efficiency, number of high-frequency oscillations per micturition; and decreases in residual volume, bladder capacity, peak bladder pressure, threshold pressure and non-voiding contractions. The 5-HT7 R antagonist, SB-269970 (10 μg/kg), partially reversed LP44-induced changes. Using PRV retrograde tracing and immunofluorescence, 5-HT7 Rs were found in the L6-S1 spinal cord Onuf's nucleus in both SI and SCI rats, but the expression was significantly greater in the SCI rats. Western blot showed significantly more 5-HT7 Rs in the ventral L6-S1 spinal cord in SCI rats. Conclusion A 5-HT7 R agonist, given i.t., improved voiding efficiency in urethane-anesthetised SCI rats, and the 5-HT7 R was significantly up-regulated in the lumbosacral cord Onuf's nucleus. If valid for humans, these findings suggest that the 5-HT7 R could be a target for therapeutic interventions.

AIMS To evaluate the therapeutic effect of TAC-302, a cyclohexenoic fatty alcohol derivative, on bladder denervation-related storage and voiding dysfunctions in rats with bladder outlet obstruction (BOO). METHODS BOO was achieved by partial ligature of the proximal urethra in female rats. Two weeks later, BOO rats were divided into two groups and treated orally with vehicle or 10 mg/kg TAC-302 twice a day for 4 weeks. Urodynamic and immunohistochemical evaluation of the bladder muscle layer was performed. In another study, the BOO rats were treated with intravenous tamsulosin at cystometry. The detrusor contractility in each group was evaluated using the modified Shafer's nomogram. RESULTS Two weeks after BOO, the rats showed significant increases in non-voiding contraction (NVCs) and residual urine volume (RUV) compared to the sham group. Moreover, 6 weeks after BOO, BOO vehicle rats showed significant increases in NVCs and RUV and decreases in detrusor contractility and in the nerve fiber density in the urinary bladder compared to the sham group. BOO-induced denervation of the urinary bladder was partially improved by oral treatment with TAC-302. Oral treatment with TAC-302 significantly reduced the amplitude and frequency of NVCs (P

AIMS Polyuria can lead to progressive chronic bladder overdistension. The impact of polyuria on the bladder has been extensively studied in settings of either diabetes or sucrose diuresis in animals. The goal of this study was to investigate the outcomes of polyuria in a hypertension setting. MATERIALS AND METHODS Male Dahl/SS rats, a hypertension model, received a high-salt or normal diet for 6 weeks. Twenty-four-hour water intake, micturition patterns, and blood pressures were recorded biweekly. Conscious cystometry was carried out at the end of this period. Bladders were collected to measure contractile force and for histological analysis. Paired t-tests were used to compare changes between Week 0 and Week 6 within each group. Unpaired t-tests were used for comparisons between groups for all parameters at Week 6. RESULTS Six weeks of high-salt diet significantly increased water intake and total urine. Blood pressures and volume of urine per micturition was higher in rats on high-salt diet. Bladder overdistension in the high-salt diet group was confirmed by cystometry, shown by a significantly higher bladder capacity, and compliance. No difference in detrusor contractility was observed between both groups. Collagen content was significantly higher in the lamina propria of the high-salt group compared to the normal group, while the opposite was observed in the muscularis. CONCLUSIONS Polyuria, in a hypertension context, leads to changes in bladder morphology and function. These findings help clarify the deleterious clinical impact of polyuria on voiding function, highlighting the variable consequences of bladder overdistension according to the underlying pathology.

Aims To investigate the role of nerve growth factor (NGF) in lower urinary tract dysfunction in mice with spinal cord injury (SCI). Methods Using 4-week SCI mice, single-filling cystometry and external urethral sphincter (EUS)-electromyography were performed under an awake condition. In some SCI mice, anti-NGF antibodies (10 µg/kg/h) were administered for 1 or 2 weeks before the urodynamic study. NGF levels in the bladder and L6/S1 spinal cord were assayed by ELISA. The transcript levels of P2X receptors and TRP channels in L6/S1 dorsal root ganglia (DRG) were measured by RT-PCR. Results In SCI mice, the area under the curve of non-voiding contractions (NVCs) during the storage phase was significantly decreased in both 1- and 2-week anti-NGF antibody-treated SCI groups. However, EUS-electromyogram parameters during voiding were not altered by the treatment. Bladder mucosal and spinal NGF levels were decreased after 2 weeks of anti-NGF antibody treatment. TRPA1 and TRPV1 transcripts in L6/S1 DRG were significantly decreased after 1- or 2-week anti-NGF treatment. Conclusions In SCI mice, NGF is involved in the emergence of NVCs in association with increased expression of TRP receptors that are predominantly found in C-fiber afferent pathways. Thus, NGF targeting treatments could be effective for treating storage problems such as detrusor overactivity after SCI.

Aims We investigated the effects of silodosin, an α1A-adrenoceptor (AR) antagonist, on bladder function, especially on non-voiding contractions (NVCs), in a male rat model of bladder outlet obstruction (BOO) by evaluating cystometry (CMG) findings and bladder mechanosensitive single-unit afferent activities (SAAs), related with microcontractions, which may be similar with NVCs and to be of myogenic origin, in the rat model. Methods BOO was created by partial ligation of the posterior urethra. At 4 days after surgery for BOO, an osmotic pump filled with silodosin (0.12 mg/kg/day) or its vehicle was subcutaneously implanted. At 10 days after surgery, CMG and SAAs measurements were taken under conscious and urethane-anesthetized conditions, respectively. The SAAs of Aδ- and C-fibers, which were identified by electrical stimulation of the pelvic nerve and by bladder distention, and intravesical pressure were recorded during constant bladder-filling with saline. Microcontractions were divided into three phases: "ascending," "descending," and "stationary." Results The silodosin-treated group showed a smaller number of NVCs in CMG measurements and lower SAAs of both Aδ- and C-fibers than the vehicle-treated group during bladder-filling. Moreover, in the vehicle-treated groups, the SAAs of both fibers for the ascending phase of microcontractions were significantly higher than those for the other two phases. On the contrary, no significant change was found between any of these three phases in the silodosin-treated group. Conclusion The present results suggest that silodosin inhibits the SAAs of mechanosensitive Aδ- and C-fibers at least partly due to suppressing myogenic bladder contractions in male BOO rats.

OBJECTIVES: To create an animal model for neurogenic underactive bladder disease (UAB) and identify markers to describe secondary myogenic changes in the bladder wall. MATERIALS AND METHODS: Male rats underwent either bilateral pelvic nerve injury or sham surgery. Four weeks after surgery functional evaluation was performed and tissue was harvested. Functional evaluation consisted of analysis of voiding pattern, 24-h urine collection in a metabolic cage, in vivo cystometry and in-vitro contractile function assessment. PCR and immunohistochemical localization of different smooth muscle cell and extracellular matrix markers was performed on bladder strips. RESULTS: After pelvic nerve injury, dry bladder weight increased and voiding contractions were absent, resulting in overflow incontinence. In-vitro contractile response to carbachol was decreased. This was paired with an upregulation of synthetic smooth muscle cell (SMC) markers mRNA expression such as retinol binding protein 1 (RBP1), myosin 10 (MYH10) and osteopontin (OPN), and a downregulation of contractile SMC marker smoothelin (SMTL). The SMTL/OPN mRNA ratio was 50 times higher in sham bladders compared to PNI bladders. CONCLUSIONS: The loss of in-vivo and in-vitro contractile function following pelvic nerve transection is characterized by a switch from a contractile to synthetic SMC phenotype, which is best characterized by the ratio SMTL/OPN mRNA expression. Modulating this phenotypical switch is a potential target for the development of UAB therapy. We suggest for the first time a set of markers that may be useful to evaluate therapeutic strategies on improvements in bladder wall structure. ispartof: NEUROUROLOGY AND URODYNAMICS vol:37 issue:5 pages:1594-1604 ispartof: location:United States status: published

We have recently identified a cholinergic chemosensory cell in the urethral epithelium, urethral brush cell (UBC), that, upon stimulation with bitter or bacterial substances, initiates a reflex detrusor activation. Here, we elucidated cholinergic mechanisms that modulate UBC responsiveness. We analyzed muscarinic acetylcholine receptor (M1–5 mAChR) expression by using RT-PCR in UBCs, recorded [Ca(2+)](i) responses to a bitter stimulus in isolated UBCs of wild-type and mAChR-deficient mice, and performed cystometry in all involved strains. The bitter response of UBCs was enhanced by global cholinergic and selective M2 inhibition, diminished by positive allosteric modulation of M5, and unaffected by M1, M3, and M4 mAChR inhibitors. This effect was not observed in M2 and M5 mAChR-deficient mice. In cystometry, M5 mAChR-deficient mice demonstrated signs of detrusor overactivity. In conclusion, M2 and M5 mAChRs attenuate the bitter response of UBC via a cholinergic negative autocrine feedback mechanism. Cystometry suggests that dysfunction, particularly of the M5 receptor, may lead to such symptoms as bladder overactivity.—Deckmann, K., Rafiq, A., Erdmann, C., Illig, C., Durschnabel, M., Wess, J., Weidner, W., Bschleipfer, T., Kummer, W. Muscarinic receptors 2 and 5 regulate bitter response of urethral brush cells via negative feedback.

AIMS We aimed to investigate the age-associated changes in movement coordination between the urinary bladder and the urethra in rats. METHODS A total of 17 female Sprague-Dawley rats were used. The rats were divided into young (3 months old) and middle-aged (12-15 months old) groups. In both groups, isovolumetric cystometry and urethral perfusion pressure (UPP) measurements were performed under urethane anesthesia. After the rhythmic bladder contractions stabilized, L-arginine, a nitric oxide (NO) substrate (100 mg/kg), was administered intravenously in both groups. Subsequently, N-nitro-L-arginine methyl ester hydrochloride (L-NAME) (50 mg/kg) was injected intravenously to inhibit NO synthase activity in both groups. RESULTS UPP change, defined as UPP nadir minus baseline UPP, was significantly smaller in middle-aged rats (64%) than in young rats (P

OBJECTIVE To investigate the effects of tadalafil on storage and voiding function in treatment-naive patients with lower urinary tract symptoms suggestive of benign prostatic hyperplasia, based on a urodynamic study. METHODS This was an open-labeled, single-center, prospective study. A total of 80 untreated outpatients with lower urinary tract symptoms suggestive of benign prostatic hyperplasia received tadalafil 5 mg/day for 12 weeks. Subjective symptoms and objective findings on voiding and storage function obtained through urodynamic studies, including cystometry and pressure flow study, were evaluated before and after treatment. RESULTS A total of 71 patients with a mean age of 70.2 years and a mean prostate volume of 45.6 mL were included in the analysis. In the International Prostate Symptom Score and Overactive Bladder Symptom Score, mean total scores significantly improved from 18.2 to 13.4 (P < 0.001) and 6.5 to 4.7 (P < 0.001), respectively, after treatment. Mean maximum bladder capacity significantly increased by approximately 35 mL (P < 0.001). Detrusor overactivity disappeared in 15 (39.5%) of 38 patients with detrusor overactivity at baseline (P < 0.001). Mean maximum flow rate on pressure flow study significantly increased from 7.1 to 9.1 mL/s (P < 0.001) and mean bladder outlet obstruction index significantly decreased from 61.3 to 47.1 (P < 0.001). CONCLUSIONS Treatment with tadalafil 5 mg once daily effectively relieves lower urinary tract symptoms based on objective improvement of storage and voiding function, such as detrusor overactivity and bladder outlet obstruction, in patients with lower urinary tract symptoms suggestive of benign prostatic hyperplasia.

The functions of the lower urinary tract have been investigated for more than a century. Lower urinary tract symptoms, such as incomplete bladder emptying, weak urine stream, daytime urinary frequency, urgency, urge incontinence and nocturia after partial bladder outlet obstruction, is a frequent cause of benign prostatic hyperplasia in aging men. However, the pathophysiological mechanisms have not been fully elucidated. The use of animal models is absolutely imperative for understanding the pathophysiological processes involved in bladder dysfunction. Surgical induction has been used to study lower urinary tract functions of numerous animal species, such as pig, dog, rabbit, guinea pig, rat and mouse, of both sexes. Several morphological and functional modifications under partial bladder outlet obstruction have not only been observed in the bladder, but also in the central nervous system. Understanding the changes of the lower urinary tract functions induced by partial bladder outlet obstruction would also contribute to appropriate drug development for treating these pathophysiological conditions. In the present review, we discuss techniques for creating partial bladder outlet obstruction, the characteristics of several species, as well as issues of each model, and their translational value.

Objectives To explore if the mechanism of the voiding dysfunction caused by spinal cord injury in rats can be improved by intravenous administration of the 5-HT2A/2C receptor agonist, DOI, and discuss whether it can be ascribed to serotonin 2A and 2C receptor up-regulation in lumbosacral cord motoneurons. Materials and Methods Female Sprague-Dawley rats were used, which were divided into two groups (Spinal cord injury group VS Normal control group). Under urethane anesthesia, cystometry was performed to examine the variation of urodynamic parameters before and after successive intrathecal administration of various doses of DOI into the lumbosacral cord. Additionally, the changes of serotonin 2A and 2C receptors in the lumbosacral cord were investigated by immunohistochemical staining and Western blot. Results Compared to controls, spinal cord injured rats had higher bladder capacity and post-void residual urine volume, and lower voiding efficiency. After spinal cord injury, DOI improved voiding efficiency likely via affecting external urethral sphincter activity. Immunohistochemical staining and Western blot analysis showed that serotonin 2A and 2C receptors were up-regulated in lumbosacral cord motoneurons. Conclusion In rats with spinal cord injury, DOI can improve voiding efficiency, and this may be due to serotonin 2A and 2C receptor up-regulation in lumbosacral cord motoneurons controlling external urethral sphincter activity. This article is protected by copyright. All rights reserved.

Objectives To compare the initial resting intravesical pressure (pves) and abdominal pressure (pabd) in the sitting position with the typical range of values, to assess the correlation between such pressures and patient xipho-pubic distance, body weight, height and body mass index (BMI), and to estimate if xipho-pubic distance can be a guide to interpret initial resting pressures in urodynamic testing. Methods Women with lower urinary tract symptomatology referred for urodynamic testing were consecutively enrolled in a prospective study. Conventional cystometry was done following “good urodynamic practices”. The correlation between initial resting pves and pabd and xipho-pubic distance, body weight, height and BMI were studied using simple and multiple linear regression analysis. Statistical significance was defined as P

Key points The lower urinary tract is regulated by reflexes responsible for maintaining continence and producing efficient voiding. It is unclear how sensory information from the bladder and urethra engages differential, state-dependent reflexes to either maintain continence or promote voiding. Using a new in vivo experimental approach, we quantified how sensory information from the bladder and urethra are integrated to switch reflex responses to urethral sensory feedback from maintaining continence to producing voiding. The results demonstrate how sensory information regulates state-dependent reflexes in the lower urinary tract and contribute to our understanding of the pathophysiology of urinary retention and incontinence where sensory feedback may engage these reflexes inappropriately. Abstract Lower urinary tract reflexes are mediated by peripheral afferents from the bladder (primarily in the pelvic nerve) and the urethra (in the pudendal and pelvic nerves) to maintain continence or initiate micturition. If fluid enters the urethra at low bladder volumes, reflexes relax the bladder and evoke external urethral sphincter (EUS) contraction (guarding reflex) to maintain continence. Conversely, urethral flow at high bladder volumes, excites the bladder (micturition reflex) and relaxes the EUS (augmenting reflex). We conducted measurements in a urethane-anaesthetized in vivo rat preparation to characterize systematically the reflexes evoked by fluid flow through the urethra. We used a novel preparation to manipulate sensory feedback from the bladder and urethra independently by controlling bladder volume and urethral flow. We found a distinct bladder volume threshold (74% of bladder capacity) above which flow-evoked bladder contractions were 252% larger and evoked phasic EUS activation 2.6 times as often as responses below threshold, clearly demonstrating a discrete transition between continence (guarding) and micturition (augmenting) reflexes. Below this threshold urethral flow evoked tonic EUS activity, indicative of the guarding reflex, that was proportional to the urethral flow rate. These results demonstrate the complementary roles of sensory feedback from the bladder and urethra in regulating reflexes in the lower urinary tract that depend on the state of the bladder. Understanding the neural control of functional reflexes and how they are mediated by sensory information in the bladder and urethra will open new opportunities, especially in neuromodulation, to treat pathologies of the lower urinary tract.

Aims We examined the effect of an E-series prostaglandin 1 (EP1) receptor antagonist on bladder activity using a rat model of spinal cord injury (SCI). Methods Female Sprague-Dawley rats were used. Six weeks after spinal cord transection, conscious-filling cystometry was performed. We evaluated the urodynamic parameters before and after intravenous (0.1 and 1.0 mg/kg) or intrathecal (0.1 and 1.0 µg) administration of SC51089, an EP1 antagonist. Spinal prostaglandin E2 (PGE2) concentration and EP1 receptor transcripts in the spinal cord and dorsal root ganglia (DRG) were measured by enzyme-linked immunosorbent assay and RT-PCR, respectively. Results The time to the first non-voiding contraction (NVC) was significantly prolonged after both 0.1 and 1.0 mg/kg of intravenous administration of SC51089 (75% prolongation at 1.0 mg/kg) whereas other parameters were not significantly changed compared to vehicle treatment. In addition, the time to the first NVC was also significantly prolonged after 1.0 µg of intrathecal administration of SC51089 (18% prolongation at 1.0 µg) whereas other parameters were not significantly changed. The spinal PGE2 concentration in SCI rats was significantly higher than that in spinal intact rats. The mRNA expressions of EP1 receptors in the both spinal cord and DRG from SCI rats were significantly higher than those from spinal intact rats. Conclusions The PGE2-induced activation of EP1 receptors in the spinal cord contributes to the initiation of detrusor overactivity in SCI. Thus, the EP1 receptor could be a therapeutic target for the treatment of neurogenic detrusor overactivity due to SCI.