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Study Objective: To explore the feasibility of nerve plane-sparing laparoscopic radical hysterectomy (NPS-LRH) as a simplified C1-type surgery for cervical cancer patients and to compare this technique with laparoscopic radical hysterectomy (LRH)., Design: A retrospective comparative study., Setting: An academic tertiary hospital affiliated with the Chinese National Cancer Center., Patients: Six hundred fifteen patients with Fédération Internationale de Gynécologie et d'Obstétrique stage Ib and IIa cervical cancer who underwent laparoscopic radical hysterectomy between January 2010 and December 2017 were enrolled. Among them, 263 patients underwent the NPS-LRH surgery, and 352 patients underwent the LRH surgery. Intraoperative data and postoperative outcomes were compared between the 2 groups., Interventions: NPS-LRH is a simplified type C1 procedure that preserves the ureteral mesentery and its nerve plane, whereas LRH is a type C2 procedure in the Querleu-Morrow surgical classification system., Measurements and Main Results: There were no statistically significant differences in age, body mass index, Fédération Internationale de Gynécologie et d'Obstétrique stage, tumor differentiation, pathological type, depth of invasion, lymphovascular space invasion, parametrial tissue invasion, lymphatic metastasis, neoadjuvant chemotherapy, or postoperative adjuvant radiotherapy and chemotherapy between the 2 groups. Compared with the LRH group, the NPS-LRH group had a shorter length of operation (238.7 ± 53.9 minutes vs 259.8 ± 56.6 minutes, p < .01), less intraoperative bleeding (p < .01), more resected lymph nodes (p = .028), shorter duration of urinary catheterization (p < .01), lower incidences of postoperative hydronephrosis (p = .044), less long-term frequent urination (p < .01), less acute urinary incontinence (p < .01), poor bladder sensation (p = .028), and constipation (p = .029). There were no statistically significant differences in the disease-free survival and overall survival between the 2 groups (p = .769 and .973, respectively)., Conclusion: NPS-LRH is a simplified, safe, and feasible type C1 operation that had a shorter length of operation, less intraoperative bleeding, more resected lymph nodes, and better postoperative bladder function compared with the LRH group. Further studies are required to assess its benefits on rectal function and long-term prognosis., (Copyright © 2019 AAGL. Published by Elsevier Inc. All rights reserved.)

A precise understanding of the autonomic innervation of the urinary tract is crucial to successful management of urologic disease given the important role that neurophysiology plays in genitourinary pathology. Recent studies using a combination of contemporary histopathology and imaging technologies have furthered our understanding of the spatial nerve distribution in the kidneys, ureters, and bladder. The findings of these recent studies may have important clinical applications in expanding our knowledge of the etiology and treatment of disease processes affecting the urinary tract. In this narrative review, our goal is to provide an overview of the autonomic innervation of the urinary tract. Specifically, we aim to provide a three-dimensional gender-specific description of renal, ureteral and vesical innervation. We also highlight some possible opportunities for clinical and investigational application of this new knowledge., (Copyright © 2019 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.)

Objective: To further evaluate relationships of the pelvic ureter to clinically relevant structures and to characterize the anatomy, histology, and nerve density of the distal ureter., Methods: In this observational cadaveric study, 35 female cadavers were examined, 30 by gross dissections and five microscopically. Ureter length and segments of pelvic ureter were measured. Closest distances between the ureter and clinically relevant points were recorded. The distal pelvic ureter and surrounding parametrium were evaluated microscopically. Nerve density was analyzed using automated quantification of peripheral nerve immunostaining. Average measurements of nerve density in the anterior and posterior quadrants surrounding the ureter were statistically compared using a two-tailed t test. Descriptive statistics were used for analyses with distances reported as mean±SD (range)., Results: Gross dissections revealed ureter length of 26.3±1.4 (range 24-29) cm (right), 27.6±1.6 (25-30.5) cm (left). Lengths of ureter from pelvic brim to uterine artery crossover were 8.2±1.9 (4.4-11.5) cm (right), 8.5±1.5 (4.5-11.5) cm (left) and from crossover to bladder wall 3.3±0.7 (2.4-5.8) cm (right), 3.2±0.4 (2.6-4.1) cm (left). Intramural ureter length was 1.5±0.3 (1-2.2) cm (right) and 1.7±1.2 (0.8-2.5) cm (left). Distances from the ureter to uterine isthmus: median 1.7 (range 1-3.0) cm (right) and 1.7 (1.0-2.9) cm (left); lateral anterior vaginal fornix 1.5 (1.0-3.1) cm (right) and 1.7 (0.8-3.2) cm (left); lateral vaginal apex 1.3 (1.0-2.6) cm (right) and 1.2 (1.1-2.2) cm (left) were recorded. Microscopy demonstrated denser fibrovascularity posteromedial to the ureter. Peripheral nerve immunostaining revealed greater nerve density posterior to the distal ureter., Conclusion: Proximity of the ureter to the uterine isthmus and lateral anterior vagina mandates careful surgical technique and identification. The intricacy of tissue surrounding the distal ureter within the parametrium and the increased nerve density along the posterior distal ureter emphasizes the importance of avoiding extensive ureterolysis in this region.

The genitofemoral nerve (GFN) has its unique anatomic characteristics of location, run and function in the male urinary system and its relationship with the ureter, deferens and inguinal region is apt to be ignored in clinical anatomic application. Clinical studies show that GFN is closely correlated with postoperative ureteral complications and pain in the inguinal region after spermatic cord or hernia repair. GFN transplantation can be used in the management of erectile dysfunction caused by cavernous nerve injury. Therefore, GFN played an important role in the clinical application of uroandrology. This review summarizes the advances in the studies of GFN in relation to different diseases in uroandrology.

Purpose: We sought to characterize and 3-dimensionally reconstruct the distribution of the autonomic innervation of the human ureter., Materials and Methods: Three male and 3 female pairs of ureters were evaluated at 2 mm serial transverse sections along the entire length of the ureter. The location of nerve tissue was immunohistochemically identified using the neuronal marker, S100 protein. ImageJ software was used to calculate nerve count and density in the adventitia and smooth muscle. Blender® graphics software was used to create a 3-dimensional reconstruction of autonomic nerve distribution., Results: Within the adventitia nerve density was highest in the mid and distal ureter (females 2.87 and 2.71 nerves per mm 2 , and males 1.68 and 1.69 nerves per mm 2 ) relative to the proximal ureter (females and males 1.94 and 1.22 nerves per mm 2 , respectively, p >0.0005). Females had significantly higher nerve density throughout the adventitia, especially in the distal ureter (2.87 vs 1.68 nerves per mm 2 , p <0.0005). In smooth muscle the nerve density progressively increased from the proximal to the distal ureter (p >0.0005). Smooth muscle nerve density was similar in the 2 genders (p = 0.928). However, in females nerve density was significantly higher in the first 2 cm of the distal ureter relative to the second 2 cm (3.6 vs 1.5 nerves per mm 2 , p <0.001) but not in males (3.0 vs 2.1 nerves per mm 2 , p = 0.126)., Conclusions: Nerve density was highly concentrated at the distal ureter in the adventitia and smooth muscle of the male and female human ureters. The female ureter had greater nerve density in the adventitia, and in smooth muscle nerves were significantly concentrated at the ureteral orifice and the ureteral tunnel., (Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Aims: Innervation of the pelvic ureter traditionally comes from the pelvic plexus. This innervation is independent: adrenergic and cholinergic. The purpose of this study was to describe more precisely the origin and nature of its innervation (adrenergic, cholinergic, nitrergic, and somatic)., Methods: Six specimens of normal human fetal pelvis (four male and two female) from 20 to 30 weeks gestation were studied. The sections of these fetuses, carried out every 5 µm without interval, were treated with Hematoxylin Eosin (HE), with Masson's trichrome (TriM), immunolabeling of smooth muscle cells with smooth anti-actin, of nerves with anti-S100 protein, anti-tyrosine hydroxylase, anti-VAChT, anti-nNOS, and with anti- peripheral myelin protein 22 (PMP 22). The slides were scanned and two-dimensional images reconstructed in 3D, and analyzed., Results: The terminal pelvic ureter travels above and inside the inferior hypogastric plexus (IHP). The nerve fibers that innervate the ureterovesical junction come mainly from the superior hypogastric plexus (SHP) which gives off the hypogastric nerves and pelvic branches of the sacral plexus that form the IHP. Most nerve fibers meet below the ureter, behind the bladder to form an ascending bundle, which innervates the pelvic ureter. Immunohistochemical analysis shows that the nerves of the pelvic ureter consist of adrenergic, cholinergic, and nitrergic fibers., Conclusion: The innervation of the distal ureter depends mainly on the SHP. This innervation is adrenergic, cholinergic, and nitrergic. It innervates the pelvic ureter in an ascending manner. This anatomical information can change rectal resection and ureteral reimplantation techniques and drug treatments for pelvic ureter stones. Neurourol. Urodynam. 36:271-279, 2017. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)

Laparoscopic radical hysterectomy has been widely performed for patients with early-stage cervical cancer. The operative techniques for nerve-sparing to avoid bladder dysfunction have been established during the past three decades in abdominal radical hysterectomy, but how these techniques can be applied to laparoscopic surgery has not been fully discussed. Prolonged operation time or decreased radicality due to less accessibility via a limited number of trocars may be a disadvantage of the laparoscopic approach, but the magnified visual field in laparoscopy may enable fine manipulation, especially for preserving autonomic nerve tracts. The present review article introduces the practical techniques for sparing bladder branches of pelvic nerves in laparoscopic radical hysterectomy based on understanding of the pelvic anatomy, clearly focusing on the differences from the techniques in abdominal hysterectomy., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Objective: Radical hysterectomy with pelvic lymphadenectomy (RHL) is the preferred treatment for early-stage cervical cancer. Although oncological outcome is good with regard to recurrence and survival rates, it is well known that RHL might result in postoperative bladder impairments due to autonomic nerve disruption. The pelvic autonomic network has been extensively studied, but the anatomy of nerve fibers branching off the inferior hypogastric plexus to innervate the bladder is less known. Besides, the pathogenesis of bladder dysfunction after RHL is multifactorial but remains unclear. We studied the 3-dimensional anatomy and neuroanatomical composition of the vesical plexus and describe implications for RHL., Materials and Methods: Six female adult cadaveric pelvises were macroscopically dissected. Additionally, a series of 10 female fetal pelvises (embryonic age, 10-22 weeks) was studied. Paraffin-embedded blocks were transversely sliced in 8-μm sections. (Immuno) histological analysis was performed with hematoxylin and eosin, azan, and antibodies against S-100 (Schwann cells), tyrosine hydroxylase (postganglionic sympathetic fibers), and vasoactive intestinal peptide (postganglionic parasympathetic fibers). The results were 3-dimensionally visualized., Results: The vesical plexus formed a group of nerve fibers branching off the ventral part of the inferior hypogastric plexus to innervate the bladder. In all adult and fetal specimens, the vesical plexus was closely related to the distal ureter and located in both the superficial and deep layers of the vesicouterine ligament. Efferent nerve fibers belonging to the vesical plexus predominantly expressed tyrosine hydroxylase and little vasoactive intestinal peptide., Conclusions: The vesical plexus is located in both layers of the vesicouterine ligament and has a very close relationship with the distal ureter. Complete mobilization of the ureter in RHL might cause bladder dysfunction due to sympathetic and parasympathetic denervation. Hence, the distal ureter should be regarded as a risk zone in which the vesical plexus can be damaged.

Objectives: To evaluate the influence of hypotonic solutions on ureteral relaxation mediated by the release of calcitonin gene-related peptide from intramural sensory nerve endings., Methods: Urine osmolarity of Sprague-Dawley rats drinking water low in salt content (Fiuggi water) or a reference water for 7 days was measured. Release of calcitonin gene-related peptide-like immunoreactivity from slices of rat ureter and urinary bladder by hypotonic solutions was assessed by an immunometric assay. The mechanism through which hypotonic solutions inhibit neurokinin A-induced phasic contractions of isolated rat ureters was evaluated by organ bath studies., Results: A 7-day consumption of Fiuggi water in rats reduced urine osmolarity by ~40%. Exposure to hypotonic solutions released calcitonin gene-related peptide-like immunoreactivity from slices of rat ureter. This response was abated in a calcium-free medium, after capsaicin desensitization, and in the presence of the unselective transient receptor potential channel antagonist, ruthenium red. Exposure of isolated rat ureteral preparations to a hypotonic solution inhibited neurokinin A-evoked phasic contraction. This response was attenuated by capsaicin desensitization and in the presence of the calcitonin gene-related peptide receptor antagonist, calcitonin gene-related peptide8-37 . Transient receptor potential vanilloid 1 or transient receptor potential vanilloid 4 antagonists did not affect the neurogenic and calcitonin gene-related peptide-dependent relaxation., Conclusion: Present data show that hypotonic solution evokes calcitonin gene-related peptide release from capsaicin-sensitive intramural sensory nerves, thus inhibiting ureteral contractility, through a transient receptor potential-dependent mechanism. However, this mechanism does not involve transient receptor potential vanilloid 1 or transient receptor potential vanilloid 4. Future studies with appropriate in vivo models should investigate the hypothesis that hypostenuric urine diffusing into the ureteral tissue might favor ureteral relaxation through this novel mechanism., (© 2015 The Japanese Urological Association.)

The article presents results of electrophysiological study of the function of the ureter in the frequency range of 0.6-35 Hz, conducted in 100 children aged 5 to 13 years with chronic pyelonephritis. Data of 35 healthy people were used as a control. It was shown that the features of ureter contractions were significantly different in the two groups. Marked decrease of amplitudes of signal harmonics was found at a frequency of 1.4 Hz in patients with pyelonephritis compared to controls. Myostimulation in pyelonephritis group has led to an approximation of harmonic amplitudes to the values of the control group.

Simultaneous recording of spontaneous electrical activity was conducted from the ending areas of the ureter (the zone bordered with pyeloureteral anastomosis and bladder, respectively), as well as of the proximal part of the bladder. Normally the activity of the distal ureter zone is a propagating from the perirenal area action potentials with increased amplitude (100 microV). In these conditions from the bladder were recorded action potentials with relatively lower values of amplitude and frequency rhythm (31.9 microV and 17 min(-1), respectively). Isolation of investigating ureter areas from each other and from the bladder leads to the emergence of spike activity in the peribladder area different from that in norm: in the background of oscillating waves arises the action potential. Isolation of the ureter from the bladder also affects the nature of the initial activity. Of all analyzed parameters of activity change (decrease) only the amplitude and the frequency of action potentials reaching respectively 24.5 microV and 14.2 min(-1). The results indicate the presence of different types of autonomous spontaneous activity in the extreme zones of the ureter and bladder. The adjustment of these activity parameters in the areas can be provided by their relationship with each other.

Background: Our objective was to concomitantly assess distribution of lymphatic and nerve structures in the parametrium., Methods: Twenty hemipelvises from ten fresh cadavers were dissected to differentiate between, three different parts of the parametrium: the lateral parametrium, the proximal and the distal part of the posterior parametrium. Histologic and immunofluorescence analyses of nerve and lymphatic structures were performed using NSE and LYVE-1 staining, respectively. The percentage of structures was independently scored as 0 (0%), 1 (1-20%), 2 (20-50%), 3 (50-80%), 4 (>80%)., Results: The lateral parametrium and the proximal part of the posterior parametrium contained both nerve (scored 2.25 and 2.50, respectively) and lymphatic (scored 2.50 and 2.00, respectively) structures. The distal part of the posterior parametrium also contained numerous nerve structures (scored 2.00) but lymphatic structures were rare (scored 0.88). No difference in nerve distribution was found according to the parts of parametrium while a significantly lower distribution of lymphatic vessels was observed in the distal part of the posterior parametrium (p=0.03)., Conclusion: The distal part of the posterior parametrium is of high nerve density and low lymphatic density raising the issue as to whether it should be removed during radical hysterectomy., (© 2013.)

Objectives: To investigate the presence of β-adrenoceptor subtypes in the human ureter, and to examine whether β(3) -adrenoceptors modulate relaxation of the human ureter., Methods: Expression of messenger ribonucleic acid of β-adrenoceptors in the human ureter was determined by reverse transcription polymerase chain reaction, and distribution of β-adrenoceptors was examined by immunohistochemistry. In functional studies, the relaxant effects of isoproterenol, procaterol, TRK-380, salbutamol and BRL 37344 on KCl-induced contraction of the human ureter were evaluated, and the inhibitory effects of isoproterenol, procaterol and TRK-380 on electrical field stimulation-induced contractions were determined., Results: Expression of β(1) -, β(2) - and β(3) -adrenoceptor messenger ribonucleic acid in the human ureter was confirmed by reverse transcription polymerase chain reaction. Positive staining for β(1) -, β(2) - and β(3) -adrenoceptor was identified not only in smooth muscle, but also in the urothelium of the human ureter. All β-adrenoceptor agonists decreased the tone of KCl-induced contractions of the human ureter with a rank order of relaxant effects of isoproterenol > procaterol > TRK-380 > salbutamol > BRL 37344. Furthermore, isoproterenol, procaterol and TRK-380 significantly decreased the amplitude of electrical field stimulation-induced contractions with a rank order of inhibitory effects of isoproterenol > procaterol > TRK-380., Conclusions: Human ureteral relaxation is mediated by both β(2) - and β(3) -adrenoceptor stimulation. β(3) -Adrenoceptor agonists have the potential to relax the human ureter, and their clinical application in the treatment of ureteral stones is expected., (© 2013 The Japanese Urological Association.)

Background/purpose: The controversy in management of primary obstructed megaureter necessitates further elucidation of the underlying pathophysiology. We evaluated smooth muscle contractility, and cholinergic, adrenergic and serotonergic activity of rabbit distal ureters after ureterovesical junction (UVJ) obstruction., Methods: Sham (SH) operation, partial obstruction (PO) and complete obstruction (CO) of the right UVJ were performed in rabbits. Three weeks later, distal ureters were isolated; spontaneous contractions (SC), contractile responses to electrical field stimulation (EFS), high KCl, carbachol, phenylephrine and serotonin were recorded., Results: SC amplitudes increased in CO compared to PO and SH (p<0.001). SC frequency was higher in CO (p<0.05). EFS-induced contraction amplitudes were greater in CO than other groups (p<0.05). High KCl-induced contractions were greater in CO (p<0.001) and PO (p<0.01). Carbachol-induced contractility was enhanced in CO and PO (p<0.05). Contractile response to phenylephrine was greater in CO than other groups (p<0.05). Serotonin induced contractile responses in CO and PO, greater in CO (p<0.05). UVJ obstruction also increased spontaneous contractility in contralateral PO and CO ureters., Conclusions: UVJ obstruction increased spontaneous and neurotransmitter-induced contractions in an obstruction grade-dependent manner. Obstruction also altered contractility of the contralateral ureters. Our findings may serve to provide further understanding of the pathophysiology of megaureter., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: Urinary retention is a known complication of using an extravesical approach for ureteral reimplantation, especially in bilateral cases. The etiology may be secondary damage to pelvic nerves during ureteral dissection. Recent literature suggests that it is possible to visually identify these nerves during a robotic assisted laparoscopic approach. We performed an exploratory study to identify and document them in pediatric patients by means of electrophysiologic recordings., Material and Methods: Seven consecutive patients undergoing robotic assisted laparoscopic ureteral reimplantation with extravesical approach were prospectively enrolled in the study. Following dissection of the ureter below the level of vas deferens in male and the uterine artery in female, staying close to the adventitia and approaching the ureterovesical junction, the fibers as described in human cadaveric studies were identified dorsomedial to the ureter and preserved. Stimulating and recording electrodes were passed through to record post-synaptic compound muscle action potentials of the bladder., Results: Even though the nerve fibers were visually identified, we were unable to consistently and reproducibly record compound muscle action potentials after stimulation of putative pelvic plexus fibers at the distal ureter, despite modulation in stimulation intensity, pulse characteristics, signal recording sensitivity and stimulator probe variation., Conclusions: In this pilot study, the inconsistent findings raise questions about the exact location of the neurovascular bundle, nature of bladder smooth muscle electrophysiology and the appropriate methodology of evaluation. This may provide a reason to reexamine the intraoperatively expected location of pelvic plexus nerve fibers., (Copyright © 2012. Published by Elsevier Ltd.)

Objective: The concept of the pelviureteric junction has existed for more than a century and yet there is no clear anatomical definition of this junction. This systematic review addresses the question of whether the human pelviureteric junction is a discrete anatomical entity., Methods: A systematic literature review was undertaken to investigate the normal gross and microscopic anatomy of the pelviureteric junction using the electronic databases MEDLINE, PubMed, Cochrane Library and Google Scholar., Results: In most individuals there is a gradual transition between the renal pelvis and ureter with no external features indicating the presence of a discrete pelviureteric 'junction'. Internally, however, luminal mucosal folds are prominent in this region. There is no consensus on the arrangement of muscle fibers at the pelviureteric junction (which may be age-dependent) although some studies suggest a focal thickening in the muscle wall consistent with physiological observations suggesting a high pressure zone capable of regulating urine flow. Studies of innervation have shown no evidence of specialization at this site., Conclusions: There is some evidence that a pelviureteric region can be delineated anatomically and physiologically. However, although it may be a useful clinical concept, there is no sound anatomical basis for an actual pelviureteric junction., (Copyright © 2011 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

The aim of this review is to describe the conceptual steps contributing to our current knowledge of purinergic signalling and to consider its involvement in the physiology and pathophysiology of the lower urinary tract. The voiding reflex involves ATP released as a cotransmitter with acetylcholine from parasympathetic nerves supplying the bladder and ATP released from urothelial cells during bladder distension to initiate the voiding reflex via P2X3 receptors on suburothelial low threshold sensory nerve fibres. This mechanosensory transduction pathway also participates, via high threshold sensory nerve fibres, in the initiation of pain in bladder and ureter. Treatment of prostate and bladder cancer with ATP is effective against the primary tumours in animal models and human cell lines, via P2X5 and P2X7 receptors, and also improves the systemic symptoms associated with advanced malignancy. Acupuncture is widely used for the treatment of urinary disorders, and a purinergic hypothesis is discussed for the underlying mechanism., (© 2012 The Author Acta Physiologica © 2012 Scandinavian Physiological Society.)

Models of the lower urinary tract are used to understand better the physiological and pathological functions of the tract and to gain insight into the relative importance of different components. The key requirement of a model is described, namely: to involve a continuous iteration with experiment; whereby experiments provide parameters and validation for components of the model, which is then used to generate hypotheses, which are tested experimentally. Different types of models are described: computational models that describe mathematically the whole urinary tract or components; physical models useful especially in testing medical devices; and tissue-engineered models. The purpose of modeling is first described in terms of the ability of models to predict the properties of the system of interest, using components that have a physiological interpretation, and to gain insight into the relative importance of different components. Examples are used to illustrate the use of modeling the urinary tract with reference to the different categories listed above., (Copyright © 2011 Wiley-Liss, Inc.)

Muscarinic receptors comprise five cloned subtypes, encoded by five distinct genes, which correspond to pharmacologically defined receptors (M(1)-M(5)). They belong to the family of G-protein-coupled receptors and couple differentially to the G-proteins. Preferentially, the inhibitory muscarinic M(2) and M(4) receptors couple to G(i/o), whereas the excitatory muscarinic M(1), M(3), and M(5) receptors preferentially couple to G(q/11). In general, muscarinic M(1), M(3), and M(5) receptors increase intracellular calcium by mobilizing phosphoinositides that generate inositol 1,4,5-trisphosphate (InsP3) and 1,2-diacylglycerol (DAG), whereas M(2) and M(4) receptors are negatively coupled to adenylyl cyclase. Muscarinic receptors are distributed to all parts of the lower urinary tract. The clinical use of antimuscarinic drugs in the treatment of detrusor overactivity and the overactive bladder syndrome has focused interest on the muscarinic receptors not only of the detrusor, but also of other components of the bladder wall, and these have been widely studied. However, the muscarinic receptors in the urethra, prostate, and ureter, and the effects they mediate in the normal state and in different urinary tract pathologies, have so far not been well characterized. In this review, the expression of and the functional effects mediated by muscarinic receptors in the bladder, urethra, prostate, and ureters, under normal conditions and in different pathologies, are discussed.

Dilated ureters are often due to mechanical obstruction. This case report describes a young adult lady with primary megaureter due to aganglionosis finally managed with extravesical Leech-Gregor Uretroneocystostomy.

Objectives: To investigate the extracellular matrix microenvironment and nerve supply of ureteropelvic junctions (UPJs) in children with intrinsic UPJ obstruction. Congenital UPJ obstruction is the most common cause of neonatal hydronephrosis. Although many studies investigating the molecular changes within this segment have been performed, the underlying mechanisms of UPJ obstruction are still unclear., Methods: Specimens were obtained from 21 children with a mean age of 103.2 months undergoing dismembered pyeloplasty. Control samples included 9 archival specimens from age-matched children without any history of urologic disease. Paraffin-embedded sections were immunostained to detect matrix metalloproteinase 2 (MMP-2), tenascin C (TN-C), and S-100 (for the neuronal supply). Expression patterns were investigated using semiquantitative high-power field magnification analyses, and the MMP-2 and TN-C immunoreactivity were scored. Differences between the 2 groups were examined statistically., Results: All UPJ specimens displayed a resolved muscular coat and replacement of smooth muscle cells by connective tissue. The degree of MMP-2 expression representing matrix turnover was statistically significantly elevated. Similarly, TN-C expression was found to be higher in obstructed specimens. Additionally, the mean S-100 staining was lower than in controls. Although S-100-positive nerve-fibers were more predominant in the adventitia with minimal submucosal and absent intramuscular staining in patient specimens, they were abundant in both adventitia and submucosa with minimal intramuscular staining in the controls., Conclusions: In intrinsic UPJ obstruction samples, a dissolved smooth muscular coat and an overexpression of extracellular matrix proteins, together with depleted nerve supply, was demonstrable., (Copyright 2010 Elsevier Inc. All rights reserved.)

1. Peristalsis in the smooth muscle cell (SMC) wall of the pyeloureteric system is unique in physiology in that the primary pacemaker resides in a population of atypical SMCs situated near the border of the renal papilla. 2. Atypical SMCs display high-frequency Ca(2+) transients upon the spontaneous release of Ca(2+) from inositol 1,4,5-trisphosphate (IP(3))-dependent stores that trigger cation-selective spontaneous transient depolarizations (STDs). In the presence of nifedipine, these Ca(2+) transients and STDs seldom propagate > 100 mum. Synchronization of STDs in neighbouring atypical SMCs into an electrical signal that can trigger action potential discharge and contraction in the typical SMC layer involves a coupled oscillator mechanism dependent on Ca(2+) entry through L-type voltage-operated Ca(2+) channels. 3. A population of spindle- or stellate-shaped cells, immunopositive for the tyrosine receptor kinase kit, is sparsely distributed throughout the pyeloureteric system. In addition, Ca(2+) transients and action potentials of long duration occurring at low frequencies have been recorded in a population of fusiform cells, which we have termed interstitial cells of Cajal (ICC)-like cells. 4. The electrical and Ca(2+) signals in ICC-like cells are abolished upon blockade of Ca(2+) release from either IP(3)- or ryanodine-dependent Ca(2+) stores. However, the spontaneous Ca(2+) signals in atypical SMCs or ICC-like cells are little affected in W/W(-v) transgenic mice, which have extensive lesions of their intestinal ICC networks. 5. In summary, we have developed a model of pyeloureteric pacemaking in which atypical SMCs are indeed the primary pacemakers, but the function of ICC-like cells has yet to be determined.

Purpose: The efficacy of the alpha1-adrenergic receptor antagonist against ureteral stones was clarified on the basis of ureteral sympathetic innervation., Methods: Semi-serial sections of retroperitoneal tissue were prepared from one each of donated male and female cadavers, and the nerve distribution in the ureter was investigated. Sympathetic nerve fibers were identified by immunostaining of tyrosine hydroxylase., Results: We were able to prepare semi-serial sections of the male right and female left ureters, in which 202 and 210 sympathetic nerve bundles were distributed. Sympathetic nerve bundles were distributed throughout the entire ureter. The number of nerve bundles was highest in the portion close to the bladder in the male right ureter (eight bundles/mm) and in the portion crossing the common iliac artery in the female left ureter (seven bundles/mm)., Conclusion: Adrenergic sympathetic nerve fibers were distributed throughout the ureter. Therefore, alpha1-adrenergic receptor antagonists may act on the entire ureter, reducing its tonus. As a result, these antagonists may be useful for improving the stone-freeing rate and inhibiting pain attacks.

The pyeloureteral function is to transport urine from the kidneys into the ureter toward the urinary bladder for storage until micturition. A set of mechanisms collaborates to achieve this purpose: the basic process regulating ureteral peristalsis is myogenic, initiated by active pacemaker cells located in the renal pelvis. Great emphasis has been given to hydrodynamic factors, such as urine flow rate in determining the size and pattern of urine boluses which, in turn, affect the mechanical aspects of peristaltic rhythm, rate, amplitude, and baseline pressure. Neurogenic contribution is thought to be limited to play a modulatory role in ureteral peristalsis. The myogenic theory of ureteral peristalsis can be traced back to Engelmann (1) who was able to localize the peristaltic pressure wave's origin in the renal pelvis and suggested that the ureteral contraction impulse passes from one ureteral cell to another, the whole ureter working as a functional syncitium. Recent studies of ureteral biomechanics, smooth muscle cell electrophysiology, membrane ionic currents, cytoskeletal components and pharmacophysiology much improved our understanding of the mechanism of how the urine bolus is propelled, how this process is disturbed in pathological states, and what could be done to improve it.

Objective: To determine the changes in number and morphology of interstitial cells of Cajal (ICC)-like cells (ICC-LC) at the ureteropelvic junction (UPJ) of rats after experimental distal ureteral obstruction., Materials and Methods: Of a total of 109 rats, 20 served as controls (C), 20 underwent sham-operations (SH) and 69 were in the study (S) groups. The UPJs were extracted initially in the C and SH groups, and 7, 14, 30, 60 and 90 days after ligation of the distal ureter in the study groups (S1, S2, S3, S4 and S5, respectively). The sections stained by c-kit anticore were studied under a light microscope., Results: The mean number of ICC-LC was 4.55+/-2.21 in C, 5.15+/-3.51 in SH, 7.40+/-6.88 in S1, 21.16+/-19.03 in S2, 12.63+/-8.16 in S3, 10.40+/-5.09 in S4, and 10.9+/-6.33 in S5. There was a statistically significant increase in ICC-LC in the study groups, except S1, compared to the C and SH groups. No significant difference was detected in Cajal cell morphology and distribution pattern between groups., Conclusions: Based on the changes in number of ICC-LC at the UPJ after obstruction of the distal ureter compared with the limited data available in the literature, we suggest that ICC-LC have a close relationship with motility of the ureter.

Background: To validate its safety and efficacy, we evaluated our preliminary results of the three-port minilaparoscopic nerve-sparing extravesical ureteral reimplantation for patients with vesicoureteral reflux (VUR)., Methods: Between July 2005 and February 2007, 9 consecutive patients (4 girls and 5 boys) with a mean age of 3.4 years (range, 7 months to 5 years) underwent a minilaparoscopic nerve sparing extravesical ureteral reimplantation for VUR. A 30-degree 3-mm telescope and two 3-mm trocars were used for the reimplantation. Minimal handling and dissection of the ureter and ureterovescial junction was adhered to spare the nerves., Results: A total of 14 ureters were reimplanted (4 unilateral and 5 bilateral). Mean follow-up period was 8.7 months. The mean operative time was 170 minutes in unilateral reimplantations and 218 minutes in the bilateral one. There was no intraoperative complication. All patients resumed oral intake in the first postoperative morning. The Foley catheters were removed within 24-36 hours after surgery. None of them had urinary retention after catheter removal. Voiding cystourethrography was done 3-4 months after surgery. A complete resolution of reflux was identified in 11 of 14 units, a downgrading of reflux in 2 of 14 units, and ureterovesical junction stenosis in 1 of 14. Open reimplantation was done for the ureter with postoperative ureterovesical junction stenosis., Conclusions: The three-port minilaparoscopic nerve-sparing extravesical ureteral reimplantation was a safe, effective techinique for the treatment of VUR.

Aims: The morphology and functional importance of the autonomic nervous system in the upper urinary tract is still not completely understood. Previous histological studies investigating the innervation of the urinary tract have mainly used conventional sections in which the three-dimensional structure of the intramural innervation is difficult to achieve. In contrast, the whole-mount preparation technique is a suitable method for visualizing the distribution of the mesh-like neuronal networks within the urinary tract., Methods: The distribution and regional variation of neurofilament (NF), tyrosine hydroxylase (TH), choline acetyltransferase (ChAT), and substance P-immunoreactive (SP-IR) neurons, as well as acetylcholinesterase (AChE) and nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d)-positive neurons were investigated using whole-mount preparations of the guinea pig upper urinary tract., Results: Two distinct nervous plexuses were detected within the muscle layers containing NF, TH, ChAT, and SP-IR nerves. AChE-positive nerves were seen in all layers. Only moderate NADPH-d-positive innervation was found. Renal pelvis, upper and lower part of the ureter showed an overall increased innervation compared to the middle portion of the ureter. Ganglia were found at the pelviureteric border displaying NF and TH immunoreactivity., Conclusion: The whole-mount preparation technique provides an elegant method for assessing the three-dimensional architecture of ureteral innervation. The guinea pig upper urinary tract is richly supplied with adrenergic, cholinergic, nitrergic, and sensory nerves which suggest that the autonomous nervous system plays an important role in controlling ureteral motility and blood flow., ((c) 2007 Wiley-Liss, Inc)

Purpose: We compared myocyte apoptosis index, microvessel density and nerve supply as well as muscular and collagen composition in the obstructed ureteral endings of children with primary obstructive megaureter and normal controls., Materials and Methods: Tissue specimens were obtained during ureteral reimplantation in 16 patients with primary obstructive megaureter. For the control group normal ureteral endings were taken at autopsy from 19 age and sex matched children. In all specimens we determined the myocyte apoptosis index, number of CD31 positive microvessels, alpha-actin positive muscular component and number of nerve terminals. The collagen fibers were also specifically stained., Results: The myocyte apoptosis index was higher in obstructed vesicoureteral junctions (10.14%+/-1.03%) compared to controls (2.11%+/-0.21%, p<0.001). Mean number of vascular elements per microscopic field was lower in ureteral endings of patients with obstructive megaureter compared to controls (p<0.001). The number of nerve endings was also significantly lower in obstructed ureteral endings. There was a negative correlation between the number of microvessels and myocyte apoptosis index in both study groups. In obstructed megaureters the number of nerve endings was also negatively correlated with myocyte apoptosis index but positively correlated with the number of microvessels. In obstructed vesicoureteral junctions the proportion of muscular component was lower and the proportion of collagen fibers was higher compared to normal controls. Positive correlation was found between the myocyte apoptosis index and the percentage of collagenous component in both study groups., Conclusions: Congenital defective vascular development may result in myocyte apoptosis, and reduction of neural elements and muscular components in obstructed vesicoureteral junctions. Subsequent substitution of connective tissue may lead to functional obstruction in primary obstructive megaureter.

Spontaneous electrical activity of the rat ureters per bladder zone was studied. In area of ureter connection with bladder, slow-wave activity was revealed. In bladder bordering ureter zone, rapid spike activity was found that was fully correlated with the genesis of upper located fluctuation processes.

Purpose: The mechanisms underlying functional maturation of the ureterovesical junction during infancy are still not fully understood. We analyzed the development of smooth muscle components of the ureterovesical junction and their nerve supply in the fetal, newborn and adolescent pig., Materials and Methods: Bladder specimens were obtained from porcine fetuses at gestational ages 60 days (5) and 90 days (5), newborn piglets (5) and 6-month-old pigs (4). Serial sections of the ureterovesical junction were investigated by Masson's trichrome, and hematoxylin and eosin histological staining, enzyme immunohistochemistry for alpha-smooth muscle actin and desmin, as well as double immunofluorescence staining using the neuronal marker peripherin and smooth muscle actin., Results: At day 60 the detrusor muscle already consisted of distinctive muscle bundles with rich innervation, while the smooth muscle coat of the extravesical ureter and subsequently the intravesical ureter had only started to differentiate. At day 60 innervation of the extravesical ureteral smooth muscle was well developed, while the innervation of the intramural part did not mature until birth. Muscle fibers of the periureteral sheath were well distinguishable at day 60 but innervation of these fibers was sparse during fetal life and showed a remarkable increase during the postnatal period. All smooth muscle components showed a striking increase in muscle bulk between the neonatal and adolescent stages., Conclusions: Our findings show that the smooth muscle components and innervation of the ureterovesical junction continue to mature during the postnatal period. This may have implications for managing ureterovesical junction disorders.

The effects of an acute increase in intraureteral pressure (IUP) on pelvic-urethra reflex potentiation were examined in urethane-anesthetized rats by recording the external urethral sphincter electromyogram activities evoked by the pelvic afferent stimulation. Compared with a single action potential elicited by the test stimulation (TS; characterized by an intensity that evoked a constant reflex response without facilitation, 1/30 Hz, 1.03 +/- 0.12 spikes/stimulation, n = 7), the repetitive stimulation [RS; identical stimulation intensity as the TS (1 Hz)] significantly induced spinal reflex potentiation (SRP; 16.90 +/- 2.00 spikes/stimulation, P < 0.01, n = 7). Such SRP was significantly attenuated by intrathecal 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo (F) quinoxaline [NBQX; a glutamatergic alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionat (AMPA) receptor antagonist] and d-2-amino-5-phosphonovalerate [APV; a glutamatergic N-methyl-d-aspartate (NMDA) antagonist; the spike number per stimulation: 11.0 +/- 0.70 for NBQX, 1.01 +/- 0.30 for APV, and 16.90 +/- 2.0 for RS, respectively, n = 7, P < 0.01]. Acute stepwise elevations of IUP gradually attenuated and eventually abolished the RS-induced SRP (16.80 +/- 1.30, 17.00 +/- 1.30, 16.30 +/- 1.30, 10.50 +/- 1.80, 8.80 +/- 1.90, 3.50 +/- 1.60, 0.80 +/- 0.20, 0.70 +/- 0.20, and 0.20 +/- 0.10 spikes/stimulation at intraureteral pressure of 0, 2.5, 5, 7.5, 10, 12.5, 15, 17.5, and 20 cmH(2)O, respectively, n = 7). Intrathecal NMDA (a glutamatergic NMDA receptor agonist) and bicuculline (a GABA receptor antagonist) both reversed the abolition of RS-induced SRP caused by unilateral ureteral distension (14.0 +/- 4.04 and 8.00 +/- 1.53 spikes/stimulation, respectively, n = 7, P < 0.01). All the results suggested unilateral ureteral distension might compensatorily relax the urethra via GABAergic inhibition of NMDA-dependent SRP.

Purpose: We assessed the smooth muscle cell apoptosis along with changes in cellular and extracellular components of the ureteropelvic junction in 23 patients with unilateral obstruction and compared them with 25 autopsies from ureteropelvic junction regions of age matched cadavers., Materials and Methods: Tissue specimens obtained from pyeloplasty were divided into 3 sections-renal pelvis above the obstruction, obstructed ureteropelvic junction and ureter below the obstructed region. For the control group the normal ureteropelvic junctions of age matched infants were autopsied. In paraffin embedded sections we determined myocyte apoptosis index (using TUNEL assay), and the amount of muscular components and nerve terminals (using image analysis techniques after immunohistochemical staining). The collagen and elastin fibers were specifically stained for evaluation of changes in extracellular matrix., Results: Smooth muscle cell apoptosis index was significantly increased at the site of ureteropelvic junction obstruction (5.68 +/- 0.18) compared to normal autopsied ureteropelvic junctions (3.60 +/- 0.11) and 2 other sections of obstructed ureteropelvic junction complex (renal pelvis 4.73 +/- 0.16, and ureter 3.97 +/- 0.16). The number of nerve terminals and the percentage of muscular component were significantly lower at the obstructed segments of affected patients compared to normal ureteropelvic junctions. Meanwhile, collagen fibers formed a significantly higher proportion of ureteral wall at the site of obstruction. Interestingly, there was negative correlation between myocyte apoptosis indices and number of nerve endings as well as amount of muscular components at the site of ureteropelvic junction obstruction. However, positive correlations were found between smooth muscle cell apoptosis and the percentage of collagen and elastin fibers., Conclusions: Our findings suggest an important role for myocyte apoptosis and defective neural development in the pathogenesis of congenital ureteropelvic junction obstruction that could pave the road for the emergence of new therapeutic modalities.

An alternative model for the measurement of ureteral peristalsis is described using the goat ureter. Ureters from freshly slaughtered goats (Capra aegagous hircus) were collected from a local slaughter house. The peristaltic reflex of these preparations was recorded using a specially designed apparatus. The preparations were mounted so that contractile responses to drugs could be recorded isometrically. Histological studies were undertaken to enable a correlation to be made between the anatomical observations and the functional studies. The spontaneous peristaltic reflex of the goat ureter (7 +/- 2 per 2 min) showed a 50% increase in the frequency of contraction (13.66 +/- 1.6, P<0.001) after application of histamine at a concentration of between 6.512 microM and 13.024 microM, but was blocked completely by 10.4 microM of pheniramine (P>0.05). The reflex was not blocked by the H2 blocker ranitidine (P<0.001). The effects of acetylcholine were variable. Calcium chloride at 6.8 microM resulted in a tetanic response (P<0.001). Nicorandil showed partial inhibition of spontaneous peristaltic reflex at 189.4 microM and complete inhibition at 473.4 microM (P<0.001). Although acetylcholine did not show any appreciable effect on the isometric contractions at a maximum dose of 275.2 microM, adrenaline increased the frequency of contractions by 8.2 +/- 6.5 (P<0.001), while salbutamol and isoprenaline had no effect. The histology revealed a striking resemblance to the human ureter, with a structure that explained the responses obtained. The anatomic, physiologic and histological similarities to the human ureter make it an effective alternative in tropical countries for research on ureteral peristalsis.

Storage and periodic expulsion of urine is regulated by a neural control system in the brain and spinal cord that coordinates the reciprocal activity of two functional units in the lower urinary tract (LUT): (a) a reservoir (the urinary bladder) and (b) an outlet (bladder neck, urethra and striated muscles of the urethral sphincter). Control of the bladder and urethral outlet is dependent on three sets of peripheral nerves: parasympathetic, sympathetic and somatic nerves that contain afferent as well as efferent pathways. Afferent neurons innervating the bladder have A-delta or C-fibre axons. Urine storage reflexes are organized in the spinal cord, whereas voiding reflexes are mediated by a spinobulbospinal pathway passing through a coordination centre (the pontine micturition centre) located in the brainstem. Storage and voiding reflexes are activated by mechanosensitive A-delta afferents that respond to bladder distension. Many neurotransmitters including acetylcholine, norepinephrine, dopamine, serotonin, excitatory and inhibitory amino acids, adenosine triphosphate, nitric oxide and neuropeptides are involved in the neural control of the LUT. Injuries or diseases of the nervous system as well as disorders of the peripheral organs can produce LUT dysfunctions including: (1) urinary frequency, urgency and incontinence or (2) inefficient voiding and urinary retention. Neurogenic detrusor overactivity is triggered by C-fibre bladder afferent axons, many of which terminate in the close proximity to the urothelium. The urothelial cells exhibit 'neuron-like' properties that allow them to respond to mechanical and chemical stimuli and to release transmitters that can modulate the activity of afferent nerves.

During the pelvic surgery ureters are dissected until they flow to the bladder. For this reason surgen must be knowleadgable about the anatomy of the vesico-ureteral unit and the blood supply of the ureters,because the majority of the early and late complications, especially following pelvic irradiation,are related to the function of kidneys and ureters. In the present review attention is paid on the ureters as an anatomical marker during the performance of radical hysterectomy and on the possible intraoperative complications, identification and avoidance of ureteral injuries,as well. Authors also discussed on the management of ureteral damages.

We studied functional asymmetry in the innervation of smooth muscle organs (right and left ureter, and right and left fallopian tubes). Asymmetry in the innervation of the right and left ureter is provided by activation of the purinergic system. Asymmetry in the innervation of the fallopian tubes is determined by the purinergic and serotoninergic mechanisms.

This study was conducted to determine whether adenosine 5'-triphosphate (ATP) contributes to nociceptor activity induced by ureter distension. Multifibre recordings of ureter afferents were made using the guinea pig ureter preparation perfused in vitro. Distension of the ureter resulted in an initial rapid and later maintained increase in afferent nerve discharge. Intraluminal application of ATP (10-1000 microM, 0.1 ml/min for 3 min) or alpha,beta-meATP (10-1000 microM) mimicked these increases in afferent activity. The afferent responses consisted of fast and slow components. Both agonists caused a sensitisation of the afferents to ureter distensions. TNP-ATP (30 microm), a P2X3 receptor antagonist, and the non-specific P2 antagonist, PPADS (100 microm), blocked the rapid and reduced the slower response to ATP. The remaining responses were blocked by the selective A1 receptor antagonist, DPCPX. TNP-ATP and PPADS reduced distension-induced afferent activity. The selective ecto-ATPase inhibitor, ARL-67156 (100, 200 microM) and suramin (100, 200 microM), an ecto-nucleotidase inhibitor as well as a P2 receptor antagonist, produced an increase in baseline and distension-induced discharge. These results indicate that the ureter epithelium may tonically (at rest) as well as phasically (on distension) release ATP, which stimulates afferent terminals by interacting with multiple P2 and P1 receptors.

Purpose: Prolonged urinary retention remains a controversial and feared complication following bilateral extravesical ureteral reimplantation. We report a modified approach to limit detrusor nerve damage during extravesical correction of bilateral ureteral reflux that significantly reduces this adverse outcome., Materials and Methods: A modified approach to the distal detrusor dissection and ureteral mobilization, along with limited periureteral dissection, was used to perform this technique. A retrospective review of 50 patients undergoing bilateral nerve sparing extravesical ureteral reimplantation (NSEVR) by a single surgeon between 1997 and 2002 was completed. Patient age, vesicoureteral reflux (VUR) grade, length of hospital stay, length of surgery and outcome were evaluated., Results: The study included 36 girls and 14 boys, with an average age of 4 years 11 months (range 1 to 14 years). Average preoperative VUR grade was 2.61 (range 1 to 5). Average length of surgery when NSEVR was the only procedure performed was 105 minutes (range 54 to 185) and average length of hospital stay was 1.76 days (0 to 3). Transient urinary retention developed in 1 child on postoperative day 1, with a successful trial of voiding the next day. The rate of immediate urinary retention was 2%. There was no long-term urinary retention, voiding dysfunction or urinary tract infections., Conclusions: NSEVR for the correction of bilateral VUR is a simple modification that provides a reproducible and minimally invasive approach to treatment. We believe that limited distal ureteral dissection, preservation of the medial ureterovesical hiatus and judicious manipulation of the surrounding tissues result in elimination of long-term urinary retention.

Purpose: Extracellular matrix (ECM) degrading enzymes and the nerve supply of the ureterovesical junction were investigated using immunohistochemical methods to gain insight into the pattern of refluxing ureteral endings., Materials and Methods: Specimens were obtained from ureterorenal units of 36 children undergoing reflux surgery with a mean age of 62.5 months and 9 age matched controls without reflux. Routine histological paraffin embedded sections were stained for general morphology. Indirect immunohistochemical methods assessing matrix metalloproteinase 1 were used to study the intensity of matrix turnover, and activated macrophage marker CD68 was quantified to describe scavenging of damaged ECM. The intramural neuronal network was explored using nerve specific immunoperoxidase for S-100 protein., Results: Refluxing ureteral endings demonstrated structural deficiencies of the smooth muscle wrap associated with a 3.8-fold increase of cellular matrix metalloproteinase 1 production and a significant increase of CD68+ macrophages, respectively. The S-100 pattern yielded significant diminution. Lacking B and T lymphocytes in the ECM precluded chronic inflammation., Conclusions: Refluxing ureteral endings showed a pathologically increased matrix remodeling combined with deprivation of the intramural nerve supply. Macrophage activation referring to altered morphology was represented by an increased expression of CD68 at the sites of increased ECM turnover.

Rats with an artificial stone in the left ureter display spontaneous pain behavior (ureteral 'crises') and referred hyperalgesia/contraction in the ipsilateral oblique musculature. To evaluate neuronal activation in both sensitive and motor pathways in this model, c-Fos expression was studied in the spinal cord of calculosis rats vs. sham controls. Fos-labeled cells were never observed in sham controls. In stone rats, they were found in the T10-L2 segments, throughout the dorsal horn, significantly more on the left than the right side (P < 0.002). Fos-labeled cells were also found in lamina IX, containing motoneurons; at the T11-T12 level, these were significantly more on the left than the right side (P < 0.03). Nociceptive input from the ureter thus activates not only sensory but also efferent neurons in the spinal cord, suggesting the triggering of reflex arcs by the visceral focus.

Objective: Transcranial magnetic stimulation can be used to test the motor efferents to the pelvic floor muscles. The aim of the present study was to assess the long-term test-retest reproducibility of pelvic floor MEPs., Methods: Eighteen healthy women without evidence of neurological or lower urinary diseases had serial measurements of pelvic floor MEPs with a mean test-retest interval of 39 weeks. Cortical and spinal transcutaneous magnetic stimulations were applied. Evoked potentials were recorded with concentric needle electrodes placed in the striated urethral sphincter and the puborectal muscle by a transvaginal route. Responses from the abductor hallucis were also recorded for comparison. Stimulations were performed with relaxed pelvic floor and with tonic contraction (facilitated responses). Student's t test was applied and mean latencies were plotted against differences to analyze test-retest variability., Results: There were no systematic effects of time or other variables that might differ between trials for all subjects. However, the means vs. differences plots revealed a large scatter of intra-individual test-retest values. The poor reproducibility was common for all tested pelvic floor muscles and modalities., Conclusions: The clinical use of pelvic floor MEPs is questionable.

Purpose: The anatomy of the ureterovesical junction is germane to surgical reconstruction in patients with significant reflux. In this study we refine the description of the neuroanatomy of the distal ureter and ureterovesical junction., Materials and Methods: The distal ureter and bladder including the ureterovesical junction from 6 normal human fetuses (3 female and 3 male) at 21 to 40 weeks of gestation were studied using immunohistochemical analysis and 3-dimensional imaging techniques with antibodies against the nonspecific neuronal markers S-100 and nitric oxide synthase (nNOS)., Results: Nerves were observed to occupy the medial aspect of the distal ureter. At the ureterovesical junction the nerves encircled the entire ureter. They traveled just outside Waldeyer's sheath, leaving a safe area for surgical dissection under the sheath. As the ureter tunneled into the bladder, the nerves localized to the lateral wall of detrusor muscle. The nerves originating from the ureter and bladder and innervating the trigonal area were immunoreactive to S-100 and nNOS. nNOS positive nerve fibers arising from the bladder and ureteral nerves were found spreading among the detrusor fibers in the trigonal area., Conclusions: A detailed knowledge of the distal ureteral and ureterovesical junction neuroanatomy and the pathway of these nerves in relation to the anatomical landmarks is critical for preserving bladder function. Based on these anatomical dissections, we would recommend careful dissection within Waldeyer's sheath during ureteral reconstructive surgery.

Objectives: To determine the organization of striated muscle fibre (FMS) of the rat striated sphincter (SS) and to characterize the motor endplates (MEP)., Material and Methods: The urethras of 30 male and female rats were studied. Two thousand hematein-eosin stained serial sections and 800 sections simultaneously stained for MEPs and nerve endings were studied., Results: The SMFs of the SS are organized in the urethral wall in four symmetrical bands. MEPs are predominantly found in the cranial third of the SS (22 MEPs per section). Sixty sixteen per cent of MEPs were situated in the lateral regions. Motor units were composed of a maximum of five SMFs., Conclusion: The SMFs of the SS are organized in four symmetrical bands. Myoconnective insertions of SMFs emphasize the importance of the connective tissue in their contractile action. They are innervated by a single MEP, in the same way as skeletal striated muscle fibres. In the SS, MEPs are predominantly located laterally to the right and to the left. The specific organization of motor units suggests an original mechanism of reinforcement of muscle contraction of the SS.

Purpose: Earlier anatomical studies have shown a close connection between the ureterovesical junction and detrusor innervation. It prompted us to develop an animal model to demonstrate the risk of partial or complete impairment of this neuronal connection during antireflux surgery., Materials and Methods: Six female Göttinger minipigs were anesthetized and laminectomized. After placement of the S3 sacral nerves into separate electrode compartments of a modified Brindley electrode the lower urinary tract was exposed by an abdominal midline incision. After bladder instillation with 150 ml NaCl 1 bilateral and 2 unilateral stimulations (left and right sides) were performed and intravesical pressure was recorded urodynamically. The left ureter was then prepared circularly in 3 steps 10, 5 and 1 cm, respectively, proximal to the ureterovesical junction. After each preparation step bilateral and unilateral stimulation was repeated. Results were recorded urodynamically and video documented., Results: Bilateral stimulation before preparation of the left ureter led to a concentric detrusor contraction with an average maximum detrusor pressure of 51 cm H(2)O. Unilateral stimulation resulted in ipsilateralbound bladder tilting with an intravesical pressure of 18 and 19 cm H(2)O on the right and left sides, respectively. After preparation of the left ureter 10, 5 and 1 cm from the ureterovesical junction a maximum detrusor pressure of 17, 10 and 1 cm H(2)O was documented, respectively. While there was almost no stimulation response of the bladder after the last preparation step at 1 cm on the left ureter, the initial bladder pressure of 18 cm H(2)O could be reproduced under stimulation on the right side., Conclusions: Analogous to human cadaver studies, we were able to prove neurophysiologically strictly unilateral detrusor innervation, drawing from the pelvic plexus dorsomedial to the ureterovesical junction into the bladder. Preparation of this ureterovesical junction during antireflex surgery, coagulating measures in this area or the affixation of anchor sutures after a Vest suture involves the risk of unilateral or bilateral detrusor decentralization.

Background/purpose: It is well realized that Anderson-Hyne's pyeloplasty fails to improve the drainage pattern and renal functional parameters in a few cases of hydronephrosis because of pelviureteric junction (PUJ) obstruction. The purpose of this study is to delineate the lower extent of the abnormally innervated pelviureteric junction by S-100 immunohistochemistry, which requires surgical removal., Methods: Thirty pelviureteric junction (PUJ) specimens were analyzed by histology and by S-100 immunohistochemistry after serial sectioning of the resected ureter and compared with the variables age, calyceal separation, parenchymal thickness, differential renal function, glomerular filtration rate (GFR), and the measured constricted ureteral segment on gross examination., Results: No significant correlation was noted (P >.05) when the histology was analyzed to find any association with any of the variables studied. The length of the visible constricted segment ranged from 2 mm to 15 mm (mean, 5.37 mm). The abnormally innervated segment was much longer than the length of the visible constricted segment in 24 and of the same length in 5 specimens. However, in 1 case, the abnormal innervation segment was shorter than the macroscopic constriction by 3 mm. The maximum difference in length between the visible constriction and the lower limit of defective innervation was 8 mm., Conclusions: The abnormally innervated ureteral segment below the PUJ in hydronephrosis is longer than the visible constricted segment at the time of surgery, and the ureter should be excised at least 8 mm or more beyond the visible lower limit of the constricted segment in cases of Anderson-Hyne's pyeloplasty.

Objective: To establish a model for investigating the pathophysiology of pelvi-ureteric junction (PUJ) obstruction, using benzalkonium chloride (BCI) treatment of the upper urinary tract of rabbits, and thus further elucidate the pathophysiology of PUJ obstruction, the most common urinary tract obstruction in children., Materials and Methods: Although various histological abnormalities have been described, PUJ obstruction may be functional. Defective innervation in PUJ has been suggested to be a major factor in the failure to transmit peristaltic waves across the PUJ. Previously established animal models of hydronephrosis deal mostly with surgical obstruction of the PUJ, which does not correlate with human congenital hydronephrosis. BCl has been used to ablate selectively neurones of the gastrointestinal myenteric plexus, which generated spastic segments with impaired peristalsis. Thus 12 rabbits were treated with BCl at the PUJ; the right upper urinary tract was dissected extraperitoneally and treated with a local application of 0.1% or 0.5% BCl (six each) for 15 min. The controls were four sham-operated animals treated with saline. The animals were assessed by intravenous urography (IVU) at 4 and 8 weeks after treatment, after which the animals were killed, the upper urinary tracts removed and whole-mounts prepared. Acetylcholinesterase (AChE) histochemistry, and neurofilament and tyrosine hydroxylase (TH) single-enzyme immunohistochemistry were used to detect the intrinsic innervation., Results: None of the animals had hydronephrosis on the IVU or at death. AChE histochemistry, TH and neurofilament immunohistochemistry showed no or very few nerve fibres within the BCl-treated PUJs in both (0.1% and 0.5%) groups. After saline treatment there was normal development of the neuronal plexus within the submucosal, muscular and adventitial layers of the upper urinary tract., Conclusion: These results suggest that treatment with BCl is useful for ablating the intrinsic innervation in the upper urinary tract. Defective intrinsic innervation of the upper urinary tract did not lead to clinically or radiologically evident hydronephrosis. Further physiological studies using this model are needed to further elucidate the neuronal and myogenic influence on the development of PUJ obstruction.

Histamine changed characteristics of the perinephric spontaneous spike activity and of the spreading electrical wave. It was shown that histamine could activate latent pacemakers of the ureter's middle area. Morphological picture of the histamine effect was also shown.

Aims: To examine the effects of N-methyl-D-aspartate (NMDA) receptor antagonists on the frequency/volume (F/V) characteristics of micturition of conscious and anesthetized rats in relation to the mechanisms of renal urine output and pyelo-ureteral transport function of the upper urinary tract., Methods: Micturition F/V characteristics of 24 conscious female Sprague-Dawley rats, each weighting 160-180 g, were evaluated in a metabolic chamber. Control values of (F/V) were first obtained after administration of a 5-mL loading dose of saline solution and compared with intraperitoneal (i.p.) injection of 0.3-6.0 mg/kg of LY274614 (LY) and 0.3-40 mg/kg of dextromethorphan (DEX). Upper urinary tract studies were performed on two groups of urethane anesthetized rats (1.2 g/kg, s.c.). A group of 17 rats was used for intravenous (i.v.) injection of 1-30 mg/kg of LY and 1-10 mg/kg of DEX. In a second group of 12 rats, 0.2 mg/kg of LY and DEX were administered intracerebroventricularly (i.c.v.), by placing a catheter into the third ventricle. In anesthetized rats, continuous cystometrograms (CMG) were done while perfusing the renal pelvis with indigo carmine, and measuring pelvic and arterial pressure and as well as visualizing the transport of urine within the upper urinary tract by using videomicroscopic imaging., Results: In conscious rats, the i.p. injection of LY and DEX produced a significant and dose-dependent increase in functional bladder capacity and a considerable increase in diuresis. In anesthetized rats, i.v. and i.c.v. administration of LY and DEX affected the micturition reflex, reflected as a significant increase in bladder capacity and preleakage pressure. Videomicroscopic imaging shows dilation of the ureter and a dilution of the dyed urine after the i.v. and i.c.v. injection of LY and DEX. The frequency of ureteral peristalsis and renal pelvic contractions were significantly decreased after i.v. and i.c.v. injection of LY as well as DEX., Conclusions: The present study shows that the NMDA receptor antagonists LY and DEX given systemically (i.v. and i.p.) or intracerebroventricularly influence the micturition reflex and modulate pyelo-ureteral motility as well as the rate of urine production. From the present study, it is suggested that NMDA receptors are directly involved in regulating pyelo-ureteral peristalsis as well as in the coordination of urine transport between upper and lower urinary tract., (Copyright 2003 Wiley-Liss, Inc.)