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This study determined the effect of pelvic organ decentralization and reinnervation 1 yr later on the contribution of muscarinic and purinergic receptors to ex vivo, nerve-evoked, bladder smooth muscle contractions. Nineteen canines underwent decentralization by bilateral transection of all coccygeal and sacral (S) spinal roots, dorsal roots of lumbar (L)7, and hypogastric nerves. After exclusions, 8 were reinnervated 12 mo postdecentralization with obturator-to-pelvic and sciatic-to-pudendal nerve transfers then euthanized 8-12 mo later. Four served as long-term decentralized only animals. Controls included six sham-operated and three unoperated animals. Detrusor muscle was assessed for contractile responses to potassium chloride (KCl) and electric field stimulation (EFS) before and after purinergic receptor desensitization with α, β-methylene adenosine triphosphate (α,β-mATP), muscarinic receptor antagonism with atropine, or sodium channel blockade with tetrodotoxin. Atropine inhibition of EFS-induced contractions increased in decentralized and reinnervated animals compared with controls. Maximal contractile responses to α,β-mATP did not differ between groups. In strips from decentralized and reinnervated animals, the contractile response to EFS was enhanced at lower frequencies compared with normal controls. The observation of increased blockade of nerve-evoked contractions by muscarinic antagonist with no change in responsiveness to purinergic agonist suggests either decreased ATP release or increased ecto-ATPase activity in detrusor muscle as a consequence of the long-term decentralization. The reduction in the frequency required to produce maximum contraction following decentralization may be due to enhanced nerve sensitivity to EFS or a change in the effectiveness of the neurotransmission.

INTRODUCTION AND OBJECTIVE:This study determined the effect of pelvic organ long-term decentralization and reinnervation one year later on the contribution of muscarinic and purinergic receptors to...

Aims We sought to determine whether somatic lumbar nerve transfer to the pelvic nerve's anterior vesical branch after sacral decentralization for detrusor muscle reinnervation also leads to aberrant innervation of the bladder outlet. Methods Twenty‐six female mongrel hound dogs underwent transection of sacral dorsal and ventral spinal roots (ie, sacral decentralization). Immediately afterward, 12 received genitofemoral nerve transfer and 9 received femoral nerve branch transfer. Five were left sacrally decentralized. Controls included 3 sham‐operated and 6 unoperated. Eight months postsurgery, the bladder and urethra were injected with retrograde tracing dyes cystoscopically. After 3 weeks, detrusor and urethral pressures were assayed electrophysiologically immediately before euthanasia and characterization of neural reinnervation. Results Electrical stimulation of spinal cords or roots did not lead to increased urethral sphincter pressure in nerve transfer animals, compared with decentralized animals, confirming a lack of functional reinnervation of the bladder outlet. In contrast, mean detrusor pressure increased after lumbar cord/root stimulation. In sham/unoperated animals, urethral and bladder dye injections resulted in labeled neurons in sacral level neural structures (dorsal root ganglia [DRG], sympathetic trunk ganglia [STG], and spinal cord ventral horns); labeling absent in decentralized animals. Urethral dye injections did not result in labeling in lumbar or sacral level neural structures in either nerve transfer group while bladder dye injections lead to increased labeled neurons in lumbar level DRG, STG, and ventral horns, compared to sacrally decentralized animals. Conclusion Pelvic nerve transfer for bladder reinnervation does not impact urethral sphincter innervation.

We determined the effect of pelvic organ decentralization and reinnervation 1 yr later on urinary bladder histology and function. Nineteen canines underwent decentralization by bilateral transection of all coccygeal and sacral (S) spinal roots, dorsal roots of lumbar (L)7, and hypogastric nerves. After exclusions, eight were reinnervated 12 mo postdecentralization with obturator-to-pelvic and sciatic-to-pudendal nerve transfers, then euthanized 8-12 mo later. Four served as long-term decentralized only animals. Before euthanasia, pelvic or transferred nerves and L1–S3 spinal roots were stimulated and maximum detrusor pressure (MDP) recorded. Bladder specimens were collected for histological and ex vivo smooth muscle contractility studies. Both reinnervated and decentralized animals showed less or denuded urothelium, fewer intramural ganglia, and more inflammation and collagen, than controls, although percent muscle was maintained. In reinnervated animals, pgp9.5+ axon density was higher compared with decentralized animals. Ex vivo smooth muscle contractions in response to KCl correlated positively with submucosal inflammation, detrusor muscle thickness, and pgp9.5+ axon density. In vivo, reinnervated animals showed higher MDP after stimulation of L1–L6 roots compared with their transected L7–S3 roots, and reinnervated and decentralized animals showed lower MDP than controls after stimulation of nerves (due likely to fibrotic nerve encapsulation). MDP correlated negatively with detrusor collagen and inflammation, and positively with pgp9.5+ axon density and intramural ganglia numbers. These results demonstrate that bladder function can be improved by transfer of obturator nerves to pelvic nerves at 1 yr after decentralization, although the fibrosis and inflammation that developed were associated with decreased contractile function.

BackgroundCurrent recommendations in the United States are that subjects with a previous history of COVID-19 disease receive the full 2 dose mRNA vaccine regimen. We tested the hypothesis that humoral immune responses and reactogenicity to a SARS-CoV-2 mRNA vaccine (BNT-162b2) differ qualitatively and quantitatively in subjects with prior SARS-CoV-2 infection versus infection-naïve subjects.MethodsHealth care workers (n=61) from a single academic institution with and without prior COVID-19 received two 30 µg doses of BNT162b2 vaccine 3 weeks apart. The COVID group (n=30) received vaccine approximately 7 months post infection. IgG antibody against the Spike receptor-binding domain (RBD), serum neutralizing activity and vaccine adverse reactions were assessed every 2 weeks for 56 days after the 1st injection. A longitudinal design and long study duration allowed the onset, maximum response and initial decay rate of Spike IgG antibody to be assessed in each subject. In addition, Spike IgG antibody levels are expressed as µg / mL to provide normal values for clinical decision making.FindingsSpike IgG responses were highly variable in both groups. However, the COVID group manifested rapid increases in Spike IgG antibody and serum neutralizing activity post 1st vaccine dose but little or no increase in Spike IgG or serum neutralizing activity after the 2nd dose. In fact, Spike IgG was maximum prior to the 2nd dose in 36% of the COVID group and 0% of controls. Peak IgG antibody was lower but appeared to fall more slowly in the COVID than in the control group. Finally, adverse systemic reactions e.g., fever, headache and malaise, after both the 1st and 2nd injection were more frequent and lasted longer in the COVID group than in the control group.ConclusionsHealth care workers with prior COVID-19 demonstrate a robust, accelerated humoral immune response to the 1st dose of the COVID-19 mRNA vaccine but attenuated response to the 2nd dose. They also experience greater reactogenicity than controls. Accordingly, subjects with prior COVID-19 may require only a single dose of vaccine.

INTRODUCTION AND OBJECTIVE:The new sensory role of the urothelium and its pathological implications in bladder dysfunction has generated intense interest in identifying its pathological mediators. ...

Aims To assess bladder smooth muscle function and innervation after long-term lower spinal root transection in canines. Methods Thirteen female mixed-breed hound dogs underwent bladder decentralization, which included transection of all sacral dorsal and ventral roots caudal to L7 and hypogastric nerves, bilaterally (n = 3); all sacral roots and hypogastric nerves plus transection of L7 dorsal roots, bilaterally (n = 4); or a sham operation (n = 6). At a year after initial surgery, bladder function was assessed in vivo by stimulation of the pelvic plexus. The bladder tissue was harvested for ex vivo smooth muscle contractility studies. Remaining bladder was evaluated for nerve morphology immunohistochemically using neuronal marker PGP9.5, apoptotic activity using terminal deoxynucleotidyl transferase dUTP nick end labeling, and histopathology using a hematoxylin and eosin stain. Results Sacral root decentralization did not reduce maximum strength of pelvic plexus stimulation-induced bladder contraction, although long-term sacral dorsal and ventral root plus L7 dorsal root transection significantly decreased contraction strength. Electric field stimulation-induced contractions of the detrusor from all decentralized animals were preserved, compared to controls. Viable nerves and intramural ganglia were visualized in the bladder wall, regardless of group. There was no difference in amount of apoptosis in bladder smooth muscle between groups. Conclusion Bladder smooth muscle cells maintain their function after long-term bladder decentralization. While pelvic plexus-induced bladder contractions were less robust at 1 year after lower spinal root transection, the absence of atrophy and preservation of at least some nerve activity may allow for successful surgical reinnervation after long-term injury.

Many studies examining the innervation of genitourinary structures focus on either afferent or efferent inputs, or on only one structure of the system. We aimed to clarify innervation of the bladder, external urethral sphincter (EUS) and clitoris. Retrograde dyes were injected into each end organ in female dogs. Spinal cord, mid-bladder, and spinal, caudal mesenteric, sympathetic trunk and pelvic plexus ganglia were examined for retrograde dye-labeled neurons. Neurons retrogradely labeled from the bladder were found primarily in L7-S2 spinal ganglia, spinal cord lateral zona intermedia at S1-S3 levels, caudal mesenteric ganglia, T11-L2 and L6-S2 sympathetic trunk ganglia, and pelvic plexus ganglia. The mid-bladder wall contained many intramural ganglia neurons labeled anterogradely from the pelvic nerve, and intramural ganglia retrogradely labeled from dye labeling sites surrounding ureteral orifices. Neurons retrogradely labeled from the clitoris were found only in L7 and S1 spinal ganglia, L7-S3 spinal cord lateral zona intermedia, and S1 sympathetic trunk ganglia, and caudal mesenteric ganglia. Neurons retrogradely labeled from the EUS were found in primarily at S1 and S2 spinal ganglia, spinal cord lamina IX at S1-S3, caudal mesenteric ganglia, and S1-S2 sympathetic trunk ganglia. Thus, direct inputs from the spinal cord to each end organ were identified, as well as multisynaptic circuits involving several ganglia, including intramural ganglia in the bladder wall. Knowledge of this complex circuitry of afferent and efferent inputs to genitourinary structures is necessary to understand and treat genitourinary dysfunction. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.

Aims Lumbar to sacral rerouting surgery can potentially allow voiding via a skin-central nervous system-bladder reflex pathway. Here, we assessed if this surgery was effective in treating neurogenic bladder dysfunction/sphincter in felines. Methods Eight cats underwent spinal cord transection (SCT) at thoracic level 10/11. Unilateral L7 to S1 ventral root anastomosis was performed 1 month later in six cats. Two cats served as transection-only controls. Electrical and manual stimulation of L6-S1 dermatomes, and urodynamics were performed at 3, 5, 7, and 9/10 months post transection. At 9/10 months, cats were also evaluated by direct electrophysiological testing of anastomosed roots with urodynamics, then tissue collection and examination of the root anastomosis site and lumbosacral cord ventral horns for cells retrogradely labeled from tracer dye injected 2 weeks earlier into the bladder wall. Results At 9/10 months, four of six rerouted cats exhibited increased detrusor pressure provoked by cutaneous stimulation, one cat bilaterally. Two cats presented with a voiding stream after ipsilateral cutaneous stimulation at 7 and 9 months. All six rerouted animals showed regrowth of axons from the L7 ventral horn to the bladder, although some aberrant axonal regrowth was also observed. Conclusion L7 to S1 ventral root rerouting below the level of SCT showed successful axonal regrowth to the bladder from the L7 spinal cord segment in all rerouted animals, and induced increased detrusor pressure response to cutaneous stimulation in a subset. This feasibility study paves the way for future animal studies for bladder reinnervation.

Background Peripheral nerve interfacing has many applications ranging from investigation of neural signals to therapeutic intervention for varied diseases. This need has driven technological advancements in the field of electrode arrays and wireless systems for in-vivo electrophysiological experiments. Hence we present our fully implantable, programmable miniaturized wireless stimulation and recording devices. New method The method consists of technological advancements enabling implantable wireless recording up to 128 channels with a sampling rate of 50Khz and stimulation up to ±4 mA from 15 independent channels. The novelty of the technique consists of induction charging cages which enables freely moving small animals to undergo continuous electrophysiological and behavioral studies without any impediments. The biocompatible hermetic packaging technology for implantable capsules ensures stability for long-term chronic studies. Results Electromyographs wirelessly recorded from leg muscles of a macaque and a rat using implantable technology are presented during different behavioral task studies. The device's simultaneous stimulation and recording capabilities are reported when interfaced with the vagus and pelvic nerves. Comparison with existing method(s) The wireless interfacing technology has a large number of recording and stimulating channels without compromising on the signal quality due to sampling rates or stimulating current output capabilities. The induction charging technology along with transceiver and software interface allows experiments on multiple animals to be carried out simultaneously. Conclusions This customizable technology using wireless power transmission, reduced battery size, and miniaturized electronics has paved way for a robust, fully implantable, hermetic neural interface system enabling the study of bioelectronic medical therapies.

INTRODUCTION AND OBJECTIVES:Carbachol, a mixed muscarinic and nicotinic agonist similar to acetylcholine, is often used for in-vitro bladder contraction with the implicit assumption that it causes ...

INTRODUCTION AND OBJECTIVES:We aim to surgically reinnervate a lower motor neuron neurogenic bladder via obturator-to-pelvic and sciatic-to-pudendal nerve transfer. Behavioral observations provide the most global assessment of functional recovery. We sought to determine whether observed micturition postures disappear in decentralized animals and reappear after reinnervation.METHODS:Three groups of female canines were used: 1) Long-term survival (12 months) after transection of all ventral and dorsal sacral roots, the dorsal roots of L7 and hypogastric nerves, bilaterally (n=4); 2) Procedures described in Group 1, followed by obturator-to-pelvic nerve and sciatic-to-pudendal nerve transfer (n=3); 3) Unoperated control animals (n=3). Micturition postures were monitored for 24 hours at monthly intervals via video recording. Bacteriuria was tracked midway through the study with urine Multistix test strip assays, body temperature, and cultured urine specimens by a commercial clinical laboratory. Awake cystomet...

INTRODUCTION AND OBJECTIVES:Recognition of the urothelium as a new sensory structure and its potential role in mediating bladder dysfunction has led to great interest in identifying its pathologica...

OBJECTIVEPrevious patient surveys have shown that patients with spinal cord or cauda equina injuries prioritize recovery of bladder function. The authors sought to determine if nerve transfer after long-term decentralization restores bladder and sphincter function in canines.METHODSTwenty-four female canines were included in this study. Transection of sacral roots and hypogastric nerves (S Dec) was performed in 6 animals, and 7 animals underwent this procedure with additional transection of the L7 dorsal roots (L7d+S Dec). Twelve months later, 3 L7d+S Dec animals underwent obturator-to-pelvic nerve and sciatic-to-pudendal nerve transfers (L7d+S Dec+Reinn). Eleven animals served as controls. Squat-and-void behaviors were tracked before and after decentralization, after reinnervation, and following awake bladder-filling procedures. Bladders were cystoscopically injected with Fluoro-Gold 3 weeks before euthanasia. Immediately before euthanasia, transferred nerves were stimulated to evaluate motor function. Dorsal root ganglia were assessed for retrogradely labeled neurons.RESULTSTransection of only sacral roots failed to reduce squat-and-void postures; L7 dorsal root transection was necessary for significant reduction. Three L7d+S Dec animals showing loss of squat-and-void postures post-decentralization were chosen for reinnervation and recovered these postures 4–6 months after reinnervation. Each showed obturator nerve stimulation–induced bladder contractions and sciatic nerve stimulation–induced anal sphincter contractions immediately prior to euthanasia. One showed sciatic nerve stimulation–induced external urethral sphincter contractions and voluntarily voided twice following nonanesthetized bladder filling. Reinnervation was confirmed by increased labeled cells in L2 and the L4–6 dorsal root ganglia (source of obturator nerve in canines) of L7d+S Dec+Reinn animals, compared with controls.CONCLUSIONSNew neuronal pathways created by nerve transfer can restore bladder sensation and motor function in lower motor neuron–lesioned canines even 12 months after decentralization.

The high-pressure zone of the gastroesophageal junction acts as a multifunctional valve that comprises different groups of smooth muscles located in the distal esophagus and the proximal stomach, in addition to the extrinsic crural diaphragm, composed of skeletal muscle. In this review article, we evaluate the current literature with respect to human subjects, discussing the anatomic locations and physiologic and pharmacologic processes controlling these muscles. These muscles work individually and as a group to prevent reflux of gastric contents while allowing anterograde passage of food and liquid and retrograde passage of gas. We also reviewed new findings with respect to abnormalities that are permissive of reflux of gastric contents into the esophagus, which may lead to gastroesophageal reflux disease.

Aims Complete spinal cord injury does not block perceptual responses or inferior solitary nucleus activation after genital self-stimulation, even though the vagus is not thought to innervate pelvic structures. We tested if vagus nerve endings sprout after bladder decentralization to innervate genitourinary structures in canines with decentralized bladders. Methods Four reinnervation surgeries were performed in female hounds: bilateral genitofemoral nerve transfer to pelvic nerve with vesicostomy (GNF-V) or without (GFN-NV); and left femoral nerve transfer (FNT-V and FNT-NV). After 8 months, retrograde dyes were injected into genitourinary structures. Three weeks later, at euthanasia, reinnervation was evaluated as increased detrusor pressure induced by functional electrical stimulation (FES). Controls included un-operated, sham-operated, and decentralized animals. Results Increased detrusor pressure was seen in 8/12 GFNT-V, 4/5 GFNT-NV, 5/5 FNT-V, and 4/5 FNT-NV animals after FES, but not decentralized controls. Lumbar cord segments contained cells labeled from the bladder in all nerve transfer animals with FES-induced increased detrusor pressure. Nodose ganglia cells labeled from the bladder were observed in 5/7 nerve transfer animals (1/2 GNT-NV; 4/5 FNT-V), and from the clitoris were in 6/7 nerve transfer animals (2/2 GFNT-NV; 4/5 FNT-V). Dorsal motor nucleus vagus cells labeled from the bladder were observed in 3/5 nerve transfer animals (1/2 GFNT-NV; 2/3 FNT-V), and from the clitoris in 4/5 nerve transfer animals (1/2 GFNT-NV; 3/3 FNT-V). Controls lacked this labeling. Conclusions Evidence of vagal nerve sprouting to the bladder and clitoris was observed in canines with lower motoneuron lesioned bladders. Neurourol. Urodynam. © 2015 Wiley Periodicals, Inc.

During the past century, diverse studies have focused on the development of surgical strategies to restore function of a decentralized bladder after spinal cord or spinal root injury via repair of the original roots or by transferring new axonal sources. The techniques included end-to-end sacral root repairs, transfer of roots from other spinal segments to sacral roots, transfer of intercostal nerves to sacral roots, transfer of various somatic nerves to the pelvic or pudendal nerve, direct reinnervation of the detrusor muscle, or creation of an artificial reflex pathway between the skin and the bladder via the central nervous system. All of these surgical techniques have demonstrated specific strengths and limitations. The findings made to date already indicate appropriate patient populations for each procedure, but a comprehensive assessment of the effectiveness of each technique to restore urinary function after bladder decentralization is required to guide future research and potential clinical application.

In 1990, although the etiology and pathogenesis of the condition then referred to as “interstitial cystitis” (IC) was admitted to be largely or even completely unknown, the widely held implicit working assumptions held that it is a bladder disease. These assumptions implied that if we could discover and correct what was wrong with the bladder itself then we could cure the condition. These assumptions have proved to be largely off base. At that time, the previous suggestions that IC might have a primarily autoimmune or infectious etiology were largely abandoned. The autoimmune hypothesis still remains but has yet to be either been proven nor disproven conclusively.

Aims Detrusor underactivity, resulting in either prolonged or inefficient voiding, is a common clinical problem for which treatment options are currently limited. The aim of this report is to summarize current understanding of the clinical observation and its underlying pathophysiological entities.

Anatomical variations in lumbosacral plexus or nerves to genitourinary structures in dogs are under described, despite their importance during surgery and potential contributions to neuromuscular syndromes. Gross dissection of 16 female mongrel hound dogs showed frequent variations in lumbosacral plexus classification, sympathetic ganglia, ventral rami input to nerves innervating genitourinary structures and pudendal nerve (PdN) branching. Lumbosacral plexus classification types were mixed, rather than pure, in 13 (82%) of dogs. The genitofemoral nerve (GFN) originated from ventral ramus of L4 in 67% of nerves, differing from the expected L3. Considerable variability was seen in ventral rami origins of pelvic (PN) and Pd nerves, with new findings of L7 contributions to PN, joining S1 and S2 input (23% of sides in 11 dogs) or S1–S3 input (5%), and to PdN, joining S1–S2, unilaterally, in one dog. L7 input was confirmed using retrograde dye tracing methods. The PN also received CG1 contributions, bilaterally, in one dog. The PdN branched unusually in two dogs. Lumbosacral sympathetic ganglia had variant intra-, inter- and multisegmental connectivity in 6 (38%). Thus, the anatomy of mongrel dogs had higher variability than previously described for purebred dogs. Knowledge of this variant innervation during surgery could aid in the preservation of nerves and reduce risk of urinary and sexual dysfunctions.

ObjectiveWe aimed to refine electroneurogram techniques for monitoring hypogastric nerve activity during bladder filling, and then examined nerve activity in normal intact versus acutely decentralized bladders.MethodsEffects of electrical stimulation of hypogastric nerves or lumbar ventral roots on detrusor pressure were examined, as were effects of isoflurane versus propofol anesthetics on hypogastric nerve stimulation evoked pressure. Hypogastric nerve activity was then recorded using custom-made bipolar cuff electrodes during bladder filling before and after its transection between the spinal cord and electrode to eliminate efferent nerve signals.ResultsElectrical stimulation of hypogastric nerves evoked low amplitude detrusor pressures that did not differ between the two anesthetics. Upper lumbar (L2) ventral root stimulation evoked detrusor pressures were suppressed, yet not eliminated, after transection of hypogastric nerves and all spinal roots below L5. Afferent and efferent hypogastric nerve activity did not change with bladder filling in neuronally intact bladders yet decreased in decentralized bladders. No change in afferent activity was observed during bladder filling in either intact or decentralized bladders.ConclusionsThese findings indicate that a more complete decentralized bladder model should include transection of lumbosacral spinal roots innervating the bladder as well as hypogastric nerves. These refined electroneurogram recording methods may be suitable for evaluating the effectiveness of nerve transfer surgeries for bladder reinnervation by monitoring sensory activity in the transferred nerve.

The following discussion on the physiology of the esophagus includes commentaries on the function of the muscularis mucosa and submucosa as a mechanical antireflux barrier in the esophagus; the different mechanisms of neurological control in the esophageal striated and smooth muscle; new insights from animal models into the neurotransmitters mediating lower esophageal sphincter (LES) relaxation, peristalsis in the esophageal body (EB), and motility of esophageal smooth muscle; differentiation between in vitro properties of the lower esophageal circular muscle, clasp muscle, and sling fibers; alterations in the relationship between pharyngeal contraction and relaxation of the upper esophageal sphincter (UES) in patients with dysphagia; the mechanical relationships between anterior hyoid movement, the extent of upper esophageal opening, and aspiration; the application of fluoroscopy and manometry with biomechanics to define the stages of UES opening; and nonpharmacological approaches to alter the gastroesophageal junction (GEJ).

Object Nerve transfers are an effective means of restoring control to paralyzed somatic muscle groups and have recently been shown to be effective in denervated detrusor muscle in a canine model. A cadaveric study was performed to examine the anatomical feasibility of transferring femoral muscular nerve branches to vesical branches of the pelvic nerve as a method of potentially restoring innervation to control the detrusor muscle in humans. Methods Twenty cadavers were dissected bilaterally to expose pelvic and femoral muscular nerve branches. Ease of access and ability to transfer the nerves were assessed, as were nerve cross-sectional areas. Results The pelvic nerve was accessed at the base of the bladder, inferior to the ureter, and accompanied by inferior vesical vessels. Muscular branches of the femoral nerve to the vastus medialis and intermedius muscles (L-3 and L-4 origins) were followed distally for 17.4 ± 0.8 cm. Two muscle branches were split from the femoral nerve trunk, and tunneled inferior to the inguinal ligament. One branch was moved medially toward the base of the bladder and linked to the ipsilateral pelvic nerve. The second branch was tunneled superior to the bladder and linked to the contralateral pelvic nerve. The cross-sectional area of the pelvic nerve vesical branch was 2.60 ± 0.169 mm2 (mean ± SEM), and the femoral nerve branch at the suggested transection site was 4.40 ± 0.41 mm2. Conclusions Use of femoral nerve muscular branches from the vastus medialis and intermedius muscles for heterotopic nerve transfer of bilateral pelvic nerves is surgically feasible, based on anatomical location and cross-sectional areas.

Object Nerve transfers are effective for restoring control to paralyzed somatic muscle groups and, recently, even to denervated detrusor muscle in a canine model. A pilot project was performed in cadavers to examine the feasibility of transferring somatic nerves to vesical branches of the pelvic nerve as a method for potentially restoring innervation to control the detrusor muscle in humans. Methods Eleven cadavers were dissected bilaterally to expose intercostal, ilioinguinal, and iliohypogastric nerves, along with vesical branches of the pelvic nerve. Ease of access and ability to transfer the former 3 nerves to the pelvic vesical nerves were assessed, as were nerve cross-sectional areas. Results The pelvic vesical nerves were accessed at the base of the bladder, inferior to the ureter and accompanied by inferior vesical vessels. The T-11 and T-12 intercostal nerves were too short for transfer to the pelvic vesical nerves without grafting. Ilioinguinal and iliohypogastric nerves (L-1 origin) were identified retroperitoneally and, with full dissection, were easily transferred to the pelvic vesical nerves intraabdominally. The mean cross-sectional area of the dominant pelvic vesical branch was 2.60 ± 0.169 mm2; ilioinguinal and iliohypogastric branches at the suggested transection site were 2.38 ± 0.32 mm2 (the means are expressed ± SEM). Conclusions Use of the ilioinguinal or iliohypogastric nerves for heterotopic transfer to pelvic vesical nerves is surgically feasible, based on anatomical location and cross-sectional areas.

Object Nerve transfers are an effective means of restoring control to paralyzed somatic muscle groups and, recently, even denervated detrusor muscle. The authors performed a cadaveric pilot project to examine the feasibility of restoring control to the urethral and anal sphincters using a femoral motor nerve branch to reinnervate the pudendal nerve through a perineal approach. Methods Eleven cadavers were dissected bilaterally to expose the pudendal and femoral nerve branches. Pertinent landmarks and distances that could be used to locate these nerves were assessed and measured, as were nerve cross-sectional areas. Results A long motor branch of the femoral nerve was followed into the distal vastus medialis muscle for a distance of 17.4 ± 0.8 cm, split off from the main femoral nerve trunk, and transferred medially and superiorly to the pudendal nerve in the Alcock canal, a distance of 13.7 ± 0.71 cm. This was performed via a perineal approach. The cross-sectional area of the pudendal nerve was 5.64 ± 0.49 mm2, and the femoral nerve motor branch at the suggested transection site was 4.40 ± 0.41 mm2. Conclusions The use of a femoral nerve motor branch to the vastus medialis muscle for heterotopic nerve transfer to the pudendal nerve is surgically feasible, based on anatomical location and cross-sectional areas.

Department of Anatomy & Cell Biology, Temple University, PennsylvaniaAims: Lower motor neuron damage to sacral roots or nerves can result in incontinence and a flaccid urinary bladder.We showed bladder reinnervation after transfer of coccygeal to sacral ventral roots, and genitofemoral nerves (L1, 2origin) to pelvic nerves. This study assesses the feasibility of urethral and anal sphincter reinnervation using transferof motor branches of the femoral nerve (L2–4 origin) to pudendal nerves (S1, 2 origin) that innervate the urethral andanal sphincters in a canine model. Methods: Sacral ventral roots were selected by their ability to stimulate bladder,urethral sphincter, and anal sphincter contraction and transected. Bilaterally, branches of the femoral nerve, specifi-cally, nervus saphenous pars muscularis [Evans HE. Miller’s anatomy of the dog. Philadelphia: W.B. Saunders; 1993],were transferred and end-to-end anastomosed to transected pudendal nerve branches in the perineum, then enclosedin unipolar nerve cuff electrodes with leads to implanted RF micro-stimulators. Results: Nerve stimulation inducedincreased anal and urethral sphincter pressures in five of six transferred nerves. Retrograde neurotracing from thebladder, urethral sphincter, and anal sphincter using fluorogold, fast blue, and fluororuby, demonstrated urethral andanal sphincter labeled neurons in L2–4 cord segments (but not S1–3) in nerve transfer canines, consistent with rein-nervation by the transferred femoral nerve motor branches. Controls had labeled neurons only in S1–3 segments.Postmortem DiI and DiO labeling confirmed axonal regrowth across the nerve repair site. Conclusions: These resultsshow spinal cord reinnervation of urethral and anal sphincter targets after sacral ventral root transection and femoralnerve transfer (NT) to the denervated pudendal nerve. These surgical procedures may allow patients to regain conti-nence. Neurourol. Urodynam. 30:1695–1704, 2011. 2011 Wiley Periodicals, Inc.Key words: reinnervation; pudendal nerve; femoral nerve; urethral sphincter; anal sphincter; incontinence; spinalinjury

The following discussion of the esophagogastric junctions includes commentaries on the three component structures of the sphincteric segment between the stomach and the esophagus; the pressure contributions from the three sphincteric components in normal subjects and in gastroesophageal reflux (GERD) patients; the mechanism of action of endoscopic plication to determine the underlying pathophysiology of GERD; and in vitro muscle strip studies of defects within the gastroesophageal sphincteric segment potentially leading to GERD.

Department of Computer & Electrical Engineering, Temple University, Philadelphia, PennsylvaniaAims: This is a continuation of studies examining the effectiveness of root repairs and nerve transfers for bladderreinnervation. Our previous retrograde fluorogold tracing studies from the bladder to the spinal cord found regrowth ofaxonsfromthespinalcordthroughthenerverepairsitetothebladderwhichwasconfirmedelectrophysiologically[Ruggieriet al. J Neurotrauma 25:214–24, 2006]. The current study determines whether the pattern of axonal regrowth from therepaired nerves or roots to the bladder is different between the surgical reanastomosis methods. Methods: The caninebladder was denervated by transection of all nerve roots from the sacral spinal cord mediating bladder contraction.Reinnervation surgeries included end-on-end repair of transected sacral ventral roots, transfer of coccygeal to sacralventralroots(CGNT),ortransferofgenitofemoraltopelvicnerves(GFNT).Results: Postmortemdialkylcarbocyaninedyetracing with Neurotrace DiI from the distal pelvic nerve to the bladder wall, combined with PGP9.5 neuronal immuno-histochemistry, demonstrated innervation by DiI-labeled axons of only parasympathetic postganglionic intramuralgangliainnormalcontrolsandshamoperatedcontrols,butreinnervationofbothintramuralgangliaanddetrusormuscledirectly after repair of sacral ventral roots. GF NT and CG NT also resulted in reinnervation of both intramural gangliaanddetrusormuscle,althoughtoalesserextentthanrepairedroots.Conclusions: Bladderreinnervationwitheitherthesame nerve (orthotopic reinnervation) or with either a primarily somatic nerve (coccygeal) or a primarily sensory nerve(genitofemoral) results in reinnervation of both intramural ganglia as well as direct innervation of detrusor muscle.Neurourol. Urodynam. 30:599–605, 2011. 2011 Wiley-Liss, Inc.Key words: carbocyanines; denervation; nerve regrowth; urinary bladder

Anticholinergic medications are commonly used to treat urinary urgency and frequency. Muscarinic receptors are located in areas beyond the detrusor muscle. In this study we measured changes in central nervous system activity in patients with lower urinary tract symptoms treated with tolterodine or a placebo.A total of 20 female patients with urinary frequency were randomized to 4 weeks of treatment with tolterodine or a placebo. Functional magnetic resonance imaging based on blood oxygenation level dependant imaging of the brain during bladder filling was performed before and after treatment. For each patient the bladder was filled by a urethral catheter and emptied 5 times.Multiple brain areas showed significant activation with bladder filling compared to the empty state and many areas also showed deactivation. Overall brain activation with bladder filling was decreased after treatment in both groups. After treatment 2 areas of the parietal cortex (precuneus and postcentral gyrus) showed significantly greater activity in patients treated with tolterodine vs placebo. Two areas of the cerebellum (anterior lobe and culmen) showed significantly greater activity in the placebo group, and these were also areas of significant deactivation in the tolterodine group.Brain activity changes as well as the areas of activation after treatment of lower urinary tract symptoms in patients with an anticholinergic medication or placebo are different in the 2 groups. Whether this finding represents action at the central nervous system or the bladder level is not known.

In the immediate management of patients with spinal cord injury (SCI), patients are typically observed for a period of time to determine whether voluntary control of bladder function returns. Therefore, bladder reinnervation surgeries are not likely to be performed immediately after the injury. We performed genitofemoral to pelvic nerve transfer (GF NT) surgery in canines at 1 and 3 months after bladder denervation (transection of S1 and S2 spinal roots) to determine whether this type of bladder reinnervation surgery has potential clinical feasibility. Nerve cuff electrodes were implanted on the genitofemoral nerves proximal to the pelvic nerve transfer site. Evidence for bladder reinnervation includes (1) increased bladder pressure and urethral fluid flow following electrical stimulation in four out of 20 nerve cuff electrodes implanted on the transferred GF nerves, (2) bilateral pelvic nerve stimulation induced bladder pressure and urethral fluid flow in three of four denervated animals with 1-month delay GF NT, and in five of six denervated animals with 3-month delay GF NT, and (3) abundant L1 and L2 spinal cord cell bodies (the origin of the GF nerve) retrogradely labeled with fluorogold injected into the bladder in all 10 of the GF NT animals, except one animal on one side. This study presents initial proof of concept that GF NT is a potentially viable clinical approach to reinnervation of the lower motor neuron-lesioned urinary bladder.

Objective Surgical rerouting of neuronal pathways may allow functional reinnervation of the bladder. We aim to develop techniques to monitor afferent (sensory) nerve activity during bladder filling in normal intact bladders for eventual application to monitoring sensory reinnervation of the bladder following nerve transfer. Methods Electroneurogram recordings were performed in anesthetized rats under isoflurane (1–2% induction dose, inhalation) of: (I) sciatic nerves during stimulation of the hindpaw with Semmes-Weinstein monofilaments of varying forces (10–300 g); and (II) bladder nerves during bladder filling with infusion rate of 0.5 mL/min, in acute experiments. Bipolar cuff electrodes were wrapped around the sciatic nerve (n=7) and ureter (and associated bladder nerves) proximal to the bladder wall (n=7), to record sciatic and bladder nerve discharges, respectively. The sciatic nerve was transected between the spinal cord and the electrode, to eliminate efferent nerve signals and record afferent fibers discharge only with hindpaw stimulation. Whereas, recordings were made of the discharges of both afferent and efferent fibers from bladder nerves during bladder filling. All recordings were performed using a low noise amplifier (SR560, filtered 300 Hz–10 kHz, gain ×10k), sampled at 20 kHz using PowerLab software (AD Instruments) and displayed using LabChart software. Bladder pressure was also recorded during filling. Results Sciatic nerve recordings consistently showed increased afferent fibers discharge with increased size of monofilament used to stimulate the hindpaw, with the highest discharge observed with the 300 g monofilament and lowest with 10 g. In contrast, recording from bladder nerves showed that combined afferent and efferent discharges increased substantially in response to bladder filling in 2 of 7 rats, and increased moderately in 2 other rats. However, there was no response in the remaining rats, perhaps due to nerve damage during cuff placement. Conclusions We found an increase in afferent discharges during paw stimulation with increased monofilaments sizes. Also, recordings from the cuff around the ureter-bladder nerve complex revealed that the afferent and efferent discharges coincided with an increase in bladder pressure during bladder filling. We could not isolate single fibers (units) from these whole nerve recordings, thus we cannot report on individual nerve fiber activity. However, based on these results, we conclude that the present technique used to record nerve activity in the rat model may be suitable to record nerve activity during bladder filling in canines with surgically rerouted neural pathways. Funding Source(s) NIH 1R01NS070267

Objective We demonstrated motor reinnervation of the decentralized canine urinary bladder by increased detrusor pressure induced by electrical stimulation of the transferred genitofemoral or femoral nerves in 21 of 28 animals. We previously reported evidence of bladder and bowel fullness sensation in these new neuronal pathways based on observation of micturition and defecation postures in the reinnervated animals. Our focus here was to determine whether these postures are eliminated in decentralized animals. Methods The pelvis was decentralized by bilateral transection of the hypogastric nerves and all spinal nerve roots caudal to L7 in 6 female canines. A separate group of 6 female canines was decentralized identically with the additional bilateral transection of L7 dorsal roots. Video surveillance of the housing cages allowed measurement of the frequency and duration of urination and defecation postures at monthly intervals post operatively (PO) by observers blinded to the surgical interventions. Results In the 6 animals with intact L7 dorsal roots, 3 displayed micturition postures 1 month, 6/6 at 2 and 3 months and 5/6 at 4 months PO. In the 6 animals with the additional L7 dorsal root transections, micturition postures were observed in 2/6 at 1 and 2 months and 3/6 at 3 and 4 months PO. In the L7 dorsal root intact animals, defecation postures were observed in 0/6 at 1 month and 2/6 at 2, 3 and 4 months PO. In the L7 dorsal root transected group, 1/6 showed defecation postures at 1 and 2 months but not at 4 months, and 1/6 showed these postures at 3 and 4 months PO. Conclusions In the L7 dorsal root intact animals, although half were unable to sense bladder fullness and 0/6 could not sense bowel fullness at 1 month PO, all were able to sense bladder fullness at 2 and 3 months and all but 1 at 4 months PO, suggesting sprouting of sensory bladder innervation likely from the remaining lower lumbar dorsal root fibers. Fewer dogs with L7 dorsal root transected were able to detect bladder fullness. The ability of 3/6 animals in the L7 dorsal root transected group to sense bladder fullness at 2–4 months PO may be from sensory nerve sprouting or variations in the bladder sensory innervation, as we described previously. Bowel fullness sensation appears to be primarily mediated by sacral sensory innervation. Funding Source(s) NIH 1R01NS070267

Objective Somatic nerve transection causes rapid loss of skeletal muscle mass and contractility. While skeletal muscle degeneration following nerve injury has been well investigated, less is known about the effects of autonomic nerve transection on smooth muscle. We explored changes in the nerve-smooth muscle functional unit following sacral root decentralization to determine integrity after decreased innervation. Methods Female mixed-breed hound dogs were surgically decentralized by bilateral transection of all spinal roots caudal to L7, including the dorsal root of L7 in a subgroup. Three weeks prior to the terminal surgery, bladders were injected cystoscopically with fluorogold around the ureterovesical junction for retrograde neuronal labeling. Tissue function was tested during the terminal procedure after 6-month (n=2) and 12-month (n=6) decentralization and compared to sham/unoperated control animals (n=13). Immediately prior to euthanasia, in vivo detrusor pressure after stimulation of nerves originating from the pelvic plexus (e.g., the anterior vesicle branch) was recorded. Collected bladder and pelvic plexus tissues from controls and 6-month decentralized dogs were harvested (n=3–6/group), cryosectioned, and examined for fluorogold labeling. Bladder tissues were stained for caspase-3 and immunostaining was quantified. Gastric tissue and red blood cells within bladder walls were used as positive controls. Data was analyzed using unpaired ANOVA. Results Nerve stimulation caused a robust increase in detrusor pressure in both control and decentralized groups. Likewise, abundant fluorogold-labeled neuronal cell bodies were observed in ganglia in the pelvic plexus of both sham and decentralized animals. Immunohistochemical stain for caspase-3 showed no difference across groups. Also, we did not observe co-localization of fluorogold-positive neuronal tissue and caspase-3, or presence of caspase-3 in smooth muscle fibers of the bladder wall. Conclusions The presence of fluorogold-labeled pelvic plexus ganglia in decentralized animals demonstrates that the ganglia remained intact up to 6 months after decentralization. Caspase-3 staining results showed no increase in apoptosis in the neuronal tissues or bladder smooth muscle in decentralized dogs, suggesting no increased apoptotic cell death. No significant difference between detrusor pressure responses across groups after nerve-evoked stimulation indicates that the nerve-smooth muscle functional unit of the bladder is intact up to 12 months after injury and therefore, nerve reinnervation strategies could be successful. Funding Source(s) NIH-NINDS NS070267

Objective In experimental models, animals with induced colitis have increased urinary frequency and abnormalities in bladder contraction to cholinergic and electric field stimulation (EFS). Nuclear factor kappa B (NFκB) is a major mediator of the inflammatory response in inflammatory bowel disease and syndrome. The aim of the present study was to determine the effect of increased NFκB signalling in enteric neurons on bladder contraction with and without experimentally induced colitis. Methods Calretinin-Cre-ERT2-IKK2CA/tdTomato transgenic (TG) mice were generated and compared to littermate wild-type (WT) controls. At two months of age, the mice were treated for three days with tamoxifen causing continuous NFκB activation in enteric neuronal cells. One month later, the mice were treated with vehicle or 2.5% dextran sulfate sodium (DSS) for 7 days to induce colitis. Full thickness urinary bladder strips were stimulated with potassium and then EFS to induce nerve mediated contraction. The effect of atropine to inhibit muscarinic receptors and alpha, beta methylene ATP (ATP) to desensitize purinergic receptors was determined. Results Even though the bladder contractile response to high potassium stimulation was similar between sexes in both WT and TG mice, the EFS induced maximal contraction was greater in WT males than in WT females. Bladder strips from WT female mice had a significantly greater atropine resistant (purinergic) component of EFS induced contraction, compared to WT male mice, but this was not found in TG mice. The cholinergic component of EFS induced contraction was not different between male and female mice (WT or TG). Acute colitis significantly reduced KCl stimulated and nerve mediated contraction in bladder strips from WT female and male mice, and from TG female mice. Constitutive activation of neuronal NFκB preserved the nerve mediated and KCL induced contractile response in male mice. Acute colitis increased the purinergic component of nerve mediated contractions in male WT mice only. Conclusions Experimentally induced colitis causes decreased bladder contraction. Neuronal NFκB signalling rescued the decreased bladder contraction due to colitis, perhaps through purinergic regulation in males. Neurogenic inflammation in the bladder may cause a larger degree of bladder dysfunction in female than in male mice perhaps because females have a greater purinergic component of nerve mediated bladder contraction that does not further increase due to colitis Funding Source(s) RO1DK075684; P2ODK097819

Objective Preganglionic sympathetic axons to pelvic viscera originate from lumbar preganglionic neurons and contribute to sympathetic chain ganglia and lumbar splanchnic nerves to the inferior mesenteric ganglia (many via the hypogastric nerve). Postganglionic sympathetic axons to the urinary bladder originate mostly from L7–S2 sympathetic chain ganglia and inferior mesenteric ganglion. We tested if after bladder decentralization and transfer of a lumbar originating nerve, postganglionic sympathetic axons will sprout from the lumbar nerves to reinnervate the urinary bladder. Methods A canine lower motoneuron lesioned bladder model was created by transecting sacral nerve roots that increased detrusor pressure using intraoperative electrical stimulation, and all roots caudal to S1. Female hounds underwent bladder decentralization and then femoral or genitofemoral nerve transfer (FNT, n=10, and GFNT, n=17, respectively) to the anterior vesicle branch of the pelvic nerve, or remained decentralized (n=3). Six sham/unoperated controls were included. Bladder emptying in animals without vesicostomies was accomplished by the Credé maneuver during the 8-month recovery period (242±6.2 days). Three weeks prior to euthanasia, a retrograde dye, Fluorogold, was injected into the bladder wall lateral to ureteral orifices. At euthanasia, T10 through coccygeal sympathetic ganglia and the inferior mesenteric ganglia were collected and examined for retrogradely labeled neuronal cell bodies. Multifactoral ANOVAs were performed (with the factors segment and group). The Bonferroni method of post hoc analysis for multiple comparisons with adjusted P values (adjusted down from P

Although the 'purinergic nerve hypothesis' proposed by Burnstock in the early 1970s was met with considerable skepticism, it is now accepted that certain neurons use a purine nucleotide or nucleoside such as ATP or adenosine as a neurotransmitter. Likewise, early studies indicated that the human bladder is devoid of purinergic nerves mediating contraction; however, later studies demonstrated that purinergic nerve-mediated bladder contraction is increased in pathologic conditions such as interstitial cystitis. Cloning and sequencing studies have revealed four subtypes of adenosine receptors and eight subtypes of P2Y receptors, all of which are G-protein-coupled receptors. There are no reports of the cellular location of these receptors in the human bladder. P2X receptors are ligand-gated ion channels, and seven subunits have been cloned and sequenced. Immunohistochemical studies have determined that P2X(1,2,4) subunits are on detrusor-muscle cells, P2X(1-3,5) subunits are on bladder nerves and P2X(2,3,5) subunits are on bladder urothelial cells. Development of purinergic antagonist drugs with selectivity for P2X(1) receptors on detrusor muscle cells might be useful for treatment of detrusor overactivity. Antagonists with selectivity for P2X(3) receptors on bladder sensory nerves might be clinically beneficial for treatment of urinary urgency, and perhaps chronic pelvic pain.

During the last century, diverse studies have focused on the development of surgical strategies for restoration of function of a decentralized bladder after spinal cord or spinal root injury via repair of the original roots or by transferring in new axon sources. These techniques have included end-to-end sacral root repairs, transfer of roots from other segments to sacral roots, transfer of intercostal nerves to sacral roots, transfer of various somatic nerves to the pelvic or pudendal nerve, direct neurotization of the detrusor muscle, and creation of an artificial “skin-CNS-bladder” reflex pathway. We have comprehensively reviewed these surgical techniques, the strengths and limitations of each, and have discussed the most appropriate patient population for each procedure. Our purpose is to critically assess the potential efficacy of nerve transfer techniques as options for restoring urinary function after bladder decentralization.