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Using the thiocholine method and histological techniques the intermesenteric plexus of the pigeon was studied. The intermesenteric plexus of this species is a plexo-ganglionic structure with several (five to seven) ganglia and nerve fibres. The ganglia have an oval-, spindle- or star-like shape. Single nerve cells along the nerve fibres were observed. The intermesenteric plexus of the pigeon is situated on the ventrolateral surface of the aorta, between the cranial mesenteric artery and caudal mesenteric artery. The connections between the intermesenteric and other vegetative plexuses (coeliac plexus, mesenteric inferior plexus) and the pelvic nerve were observed.

The pelvic nerve (PN) plays a crucial role in control of bladder function. However, repair of the PN during operation or transplantation of the urinary bladder preserving PN control has never been reported. This study was undertaken to explore the possibilities of restoring PN function to the canine bladder after PN-PN reattachment and of transplanting the bladder while preserving PN function. Responses of the bladder to electrical stimulation of the PN were examined in dogs that had undergone PN-PN reattachment or auto-transplantation of the bladder with PN-PN reattachment. Cystometry was performed in dogs that had undergone bladder transplantation. Eighteen months after unilateral PN-PN reattachment, stimulation of each of five PNs sutured in five dogs elicited elevation of bladder pressure. Twelve months after bilateral PN-PN reattachments in five dogs, eight of 10 PNs stimulated elicited elevation of bladder pressure. Three of five dogs that had undergone auto-transplantation of the bladder showed a long survival. Nine months after the operation, each of the six PNs stimulated in the three dogs elicited elevation of bladder pressure. Voiding reflex was observed in two of the three dogs on cystometry. All the 13 dogs examined above preserved sufficient bladder capacity and all but one demonstrated small volume of residual urine. The above results indicate that the function of the PN to the canine bladder can be restored after PN-PN reattachment and that transplantation of the bladder preserving control of the PN is possible.

We studied evoked potentials (EP) and responses of single neurons in fields 24 and 25 of the cingulate gyrus of the cat brain cortex. The responses were elicited by stimulations of a parasympathetic, a sympathetic, and a somatic nerve (the pelvic, splanchnic, and sciatic nerves). The configuration and amplitude/temporal characteristics of both EP and neuronal responses showed that the organization of the visceral and somatic afferent inputs to the cortical fields under study is to a great extent similar. Localization of the foci of maximum activity for EP within field 24 and their overlapping, the higher responsiveness of the neurons of this field to afferent volleys as compared with that in field 25, the dominance of short-latency neuronal responses in field 24, and the presence of polysensory neurons with modally specific opposite responses in this field allow us to conclude that field 24 (compared with field 25) plays a more significant role in the perception and analysis of viscerosomatic afferent information. Taking into account earlier published data that the zones of concentration of the efferent neurons (forming a descending limbico-sympathetic discharge in the L2-L3 white connective branches and a limbico-parasympathetic discharge in the pelvic nerve) are localized within field 25 and overlap each other, we discuss the functional roles of fields 24 and 25 of the cingulate gyrus in viscerosensory and visceromotor control.

The striated muscle forms an outer sleeve around the urethra and occupies about 80% of the wall. In humans more than 60% of the muscle consists of slow, fatigue resistant type I fibres whereas in male greyhounds only about 6% are type I. Most of the remainder (70% of fibres) are type IIa which are classified as fast but can contract for several hours with little decline in amplitude. Stimulation of pudendal but not pelvic nerves produces contraction of the striated muscle and a rapid increase in urethral pressure. Pelvic nerve branches enter the striated muscle sleeve but pass through it to supply the inner layer of smooth muscle. The striated muscles are well suited to maintain contraction necessary for continence.

We studied the effects of intracolonic administration of opioid receptor agonists (ORAs) on responses of pelvic nerve afferent fibers to colorectal distension (CRD) and heat. Single-fiber recordings were made from the decentralized S1 dorsal rootlet in the rat. An approximately 7-cm length of descending colon was isolated in situ to permit intracolonic perfusion with Krebs solution, which, when the outflow was clamped, was used to distend the colon. Responses to noxious CRD (40 mmHg, 30 s) were tested after intracolonic instillation of mu-, delta- or kappa-ORAs. Intracolonic administration of the kappa-ORAs EMD 61,753 (n = 5/12) and U62,066 (n = 8/11), but not either the mu-ORA fentanyl or the delta-ORA SNC-80, concentration-dependently inhibited responses of afferent fibers. For fibers unaffected by intracolonic administration of EMD 61,753 or U62,066, intra-arterial administration of kappa-ORAs was effective. Forty-one of 54 mechanosensitive fibers also responded to intracolonic instillation of heated Krebs solution (50 degrees C). Intra-arterial injection of fentanyl or SNC-80 did not attenuate responses to heat. Either intracolonic or intra-arterial administration of EMD 61,753 or U62, 066, however, inhibited afferent fiber responses to heat. These results document that mechanical and thermal sensitivity of polymodal pelvic nerve afferent fibers innervating the rat colon can be inhibited peripherally by intracolonic instillation of kappa-ORAs.

In the rat the pelvic nerve consists of a viscerocutaneous (sensory) branch which receives information from pelvic viscera and the midline perineal region, and a somatomotor (muscular) branch which innervates the ilio- and pubococcygeous muscles. To investigate the contribution of these branches to the parturition process, the length of gestation and course of delivery were closely monitored in 43 pregnant, Wistar-strain rats randomly assigned to five groups: untreated control animals, animals in which the somatomotor branch of the pelvic nerve was bilaterally sectioned on Day 14 of gestation, animals in which the viscerocutaneous branch of the pelvic nerve was bilaterally sectioned on Day 14 of gestation, animals treated similarly to the previous group but with young delivered by C-section at term, and sham-operated controls. Sectioning the viscerocutaneous branch seriously disrupted parturition and resulted in major dystocia and a high percentage of stillbirths in all females. In contrast, sectioning the somatomotor branch had no apparent effect on parturition and no significant differences were found between females of this group and sham or control dams on any of the measures recorded. It is concluded that the viscerocutaneous branch of the pelvic nerve is vital for the normal course of parturition in the rat but that the somatomotor branch plays little role, if any.

Background: We examined the mechanism of urinary bladder motility return after bladder areflexia induced by interruption of the sacral parasympathetic outflow to the urinary bladder following damage to the sacral cord or pelvic nerves in the rat. Methods: The L6 and SI nerve bundles were resected near the vertebrae, and bilateral pelvic nerve resections (PNR) performed. Spinal cord injury (SCI) was performed by means of a legion generator at the T12 vertebra. Thirty days after PNR and SCI, cystometrograms were recorded under anesthesia. Results: In all rats subjected to PNR or SCI, overflow incontinence continued, yet some rats subjected to SCI recovered within 2 weeks after the operation. Cystometrograms showed that repetitive bladder contractions appeared in rats subjected to SCI irrespective of hypogastric nerve (HCN) innervation, while bladder contractions did not appear in rats subjected to PNR. Electrical stimulation of the HGN induced higher bladder pressure elevation in rats who underwent PNR than in rats subjected to SCI. Conclusions: These results suggest that the generation of repetitive bladder contractions induced by bladder distention after bladder areflexia requires the presence of intact pelvic nerves that transmit sacral cord-originating excitatory information to the bladder. However, the HGN system and functioning pelvic nerve ganglia are not involved in this process. Also, the connection from the preganglionic HGN to the postganglionic parasympathetic nerves in the pelvic plexus did not form after PNR.

Su, X., J. N. Sengupta, and G. F. Gebhart. Effects of opioids on mechanosensitive pelvic nerve afferent fibers innervating the urinary bladder of the rat. J. Neurophysiol. 77: 1566–1580, 1997. A total of 443 pelvic nerve afferent fibers in the L6 dorsal root of the rat were identified by electrical stimulation of the pelvic nerve; 319 (72%) were myelinated Aδ fibers with a mean conduction velocity (CV) of 11.8 m/s and 124 (28%) were unmyelinated C fibers with mean CV of 1.9 m/s. Two hundred fifty-two fibers (57%) responded to noxious urinary bladder distension (UBD; 80 mmHg); 108 were C fibers (mean CV: 1.9 m/s) and 144 were Aδ fibers (mean CV: 8.2 m/s). Forty-nine UBD-sensitive fibers were further characterized; all gave monotonic increases in firing to increasing distending pressures. Thirty-six fibers (73%) had a low-threshold (LT) for response (mean: 6 mmHg) and 13 fibers (27%) had high-thresholds (HT) for response (mean: 32 mmHg). Responses of 15 fibers to graded UBD (11 LT and 4 HT) were tested before and after instillation of 0.5 ml of 30% xylenes ( n = 11) or 5% mustard oil ( n = 4) into the bladder. The mean resting activity of 13 fibers significantly increased, and 7 fibers exhibited sensitization of responses to graded UBD 30 min after xylenes or mustard oil instillation. All 4 HT fibers were sensitized; 3 of the 11 LT fibers were sensitized (i.e., gave increased responses to UBD). The effects of opioid receptor agonists were tested on responses to noxious UBD (80 mmHg). Cumulative intraaterial doses of μ-opioid receptor agonists (morphine, 8 mg/kg, and fentanyl, 300 μg/kg) and of δ-opioid receptor agonists (DPDPE, 300 μg/kg, and SNC-80, 300 μg/kg) did not affect responses to noxious UBD. In contrast, cumulative 16 mg/kg intraarterial doses of the κ-opioid receptor agonists U50,488H, U69,593 and U62,066 dose-dependently attenuated responses to noxious UBD. There were no differences in the dose-response relationships of these drugs on afferent fibers from untreated and xylenes- or mustard oil-treated urinary bladder. These results reveal that there is a greater proportion of UBD-sensitive fibers in the L6 dorsal root (57%) than in the S1 dorsal root of the rat (38%; a previous study). The attenuation of responses to UBD by κ, but not μ or δ opioid receptor agonists suggests a potential use for peripherally acting κ opioid receptor agonists in the control of urinary bladder pain.

Background/aims Colonic peristalsis is mainly regulated via intrinsic neurons in guinea pigs. However, autonomic regulation of colonic motility is poorly understood. We explored a guinea pig model for the study of extrinsic nerve effects on the distal colon. Methods Guinea pigs were sacrificed, their distal colons isolated, preserving pelvic nerves (PN) and inferior mesenteric ganglia (IMG), and placed in a tissue bath. Fecal pellet propagation was conducted during PN and IMG stimulation at 10 Hz, 0.5 ms and 5 V. Distal colon was connected to a closed circuit system, and colonic motor responses were measured during PN and IMG stimulation. Results PN stimulation increased pellet velocity to 24.6 ± 0.7 mm/sec (n = 20), while IMG stimulation decreased it to 2.0 ± 0.2 mm/sec (n = 12), compared to controls (13.0 ± 0.7 mm/sec, P ＜ 0.01). In closed circuit experiments, PN stimulation in-creased the intraluminal pressure, which was abolished by atropine (10(-6) M) and hexamethonium (10(-4) M). PN stimulation reduced the incidence of non-coordinated contractions induced by NG-nitro-L-arginine methyl ester (L-NAME; 10(-4) M). IMG stimulation attenuated intraluminal pressure increase, which was partially reversed by alpha-2 adrenoceptor antagonist (yohimbine; 10(-6) M). Conclusions PN and IMG input determine speed of pellet progression and peristaltic reflex of the guinea pig distal colon. The stimulatory effects of PN involve nicotinic, muscarinic and nitrergic pathways. The inhibitory effects of IMG stimulation involve alpha-2 adrenoceptors.

Purpose: We determined the efficacy of the modified Ingelman-Sundberg procedure in women with urge incontinence and intractable detrusor instability.Materials and Methods: Women with urge incontinence and detrusor instability, in whom medical and behavioral therapy failed, received transvaginal local anesthesia to block the terminal pelvic nerve branches to the bladder. Urge incontinence resolved temporarily in 25 patients, who subsequently underwent modified Ingelman-Sundberg transvaginal bladder denervation. All patients underwent preoperative urodynamic evaluation but documented detrusor instability was not a requirement for surgery.Results: Of the patients 16 (64 percent) were cured of urge incontinence with substantial relief of detrusor instability, 2 (8 percent) had temporary improvement and 7 (28 percent) had no change. No patient who was cured required further surgery (mean followup 14.8 months, range 4 to 30). Use of anticholinergic agents also decreased dramatically: 5 patients used no,...

Parasympathetic discharges evoked by application of single and paired stimuli to central, corticomedial, and basolateral nuclei of the amygdala were recorded from the pelvic nerve (PN) in anesthetized and immobilized cats. The discharges were found to include three main negative waves (I, II, and III waves, appearing with the latencies of 16.0–17.8, 74–87, and 171–184 msec, respectively). The first two waves were seen most regularly. Sometimes the I wave was preceded by a super-early negative component of a low amplitude appearing with a latency of 8.5–10.7 msec. The discharges evoked by stimulation of various nuclei of the amygdala did not significantly differ from each other in their thresholds, time courses, and amplitudes, which suggests a relatively diffuse distribution of parasympathetic efferent structures in the amygdala. It was shown, using paired stimuli, that a response to the second stimulus needed a long-lasting period (a few tens of milliseconds) to be restored. The origin of the components of the amygdalofugal parasympathetic discharges recorded from the PN, as well as the corresponding pathways they spread through, are discussed. In addition, the possible origin of the positive components of the PN discharges are considered.

creased at 1 week and remained doubled at 4 weeks during continuous CMG. This was paralleled by similar increases in bladder compliance. A striking reduction (50%) in EUS EMG activity during filling was also seen with PNC. Isovolumetric CMG in the PNC groups revealed a 40% reduction in peak bladder contraction pressures over baseline and a 30% reduction in isovolumetric bladder contraction areas under the curves. CONCLUSIONS: In this preliminary study, we have shown that bilateral pelvic nerve crush in the rat is a promising, long-lasting model of UAB, demonstrating both bladder and outlet dysfunction consistent with pelvic nerve denervation. Increased ICI, bladder compliance, and decreased EUS activity are consistent with decreased afferent sensitivity with PNC. Decreased bladder contraction strength is consistent with compromised efferent function. By establishing a chronic rat model for UAB in otherwise normal animals, we can test potential therapies for treating UAB and voiding dysfunction, thereby addressing both afferent and efferent dysfunction.

OBJECTIVES: : The primary aim of this study was to identify patient characteristics potentially affecting response to office-based percutaneous nerve evaluation (PNE). Secondarily, we aimed to identify appropriate candidates to undergo office-based PNE. METHODS: : A retrospective chart review was conducted from 2000 to 2011 of female patients who underwent office-based PNE. Data were separated into 3 groups based on outcome: success, equivocal, and failure. Data examined included patient demographics, voiding dysfunction diagnosis, comorbidities, evidence of previous pelvic nerve injury, systemic hormonal status, and neurological insult of such varieties as stroke and Parkinson disease. All data were analyzed using χ analysis and analysis of variance. P < 0.05 was considered statistically significant. RESULTS: : One hundred twelve women underwent office-based PNE. Seventy-four patients (66.1%) had a successful outcome, 15 (13.4%) had an equivocal outcome, and 23 patients (20.5%) failed PNE trial. Neurological insult was the only factor of significance identified in those patients with an equivocal or unsuccessful trial of office-based PNE. After categorizing body mass index according to the World Health Organization's 2011 guidelines, no significance was found for body mass index between successful outcomes, equivocal outcomes, and failures. CONCLUSIONS: : Our cohort demonstrates that those patients who had an equivocal or failed outcome of office-based PNE were more likely to have a neurological insult. Patients with neurological insult who are considered appropriate candidates for neuromodulation trial should undergo staged implantation with quadruple tined lead in the operating room to provide these patients with the greatest opportunity for successful outcome.

1. Mapping experiments were performed in the region of the ventral posterolateral nucleus of the lateral thalamus in pentobarbitone-anesthetized cats with the aim to locate foci with input from the electrically stimulated pelvic nerve. The locations of the recording sites were verified in Nissl-stained histological sections with reference to electrolytic lesions. 2. Of the 68 visceroceptive thalamic neurons identified, 63% were located in the periphery of the ventral posterolateral nucleus (VPLp) and 34% in the dorsal, lateral, and medial aspects of the posterior complex (POd, POl, and POm, respectively) directly adjacent to VPLp. The region surrounding the middle and caudal part of the ventral posterolateral nucleus (VPL) received a much denser input from the pelvic nerve than that around the rostral pole of VPL. 3. The response latencies of the thalamic neurons to pelvic nerve stimulation ranged from 10 to 65 ms (median: 16 ms; interquartile distance: 12–20 ms) indicating a transmission of information from the pelvic space via small and large diameter myelinated fibers. 4. Seventy-nine percent of the visceroceptive neurons tested (n = 58), in addition, had low threshold somatic receptive fields that were located in 67% of the cases in regions of the lower back, the thigh, the tail and/or the heel and in 26% of the cases on the hindfoot. None of the 40 visceroceptive neurons tested with noxious mechanical stimulation of the skin responded to this kind of stimulus.(ABSTRACT TRUNCATED AT 250 WORDS)

The object of this work was to study bulbocavernosus and deep pudendal reflex (BCR and DPR) latencies and amplitudes as an indicator of pelvic nerve damage in patients with pelvic floor disorders, with or without a previous surgery. 124 women were studied: 68 were normal, 38 had genital prolapse (GP) and 18 had recurrent GP. Clinical and urodynamic studies were carried out. Delayed reflex responses were found in 44/56 patients (79%), 27/38 in the genital prolapse group (71%) and 17/18 in the group with recurrent GP (94%). Thus the evaluation of pelvic floor reflex responses is a test that can be taken into account in the diagnosis of management of pelvic floor disorders.

1. Single-unit activity was recorded from S1 sacral dorsal root afferent fibers in the anesthetized rat. A total of 364 afferent fibers were identified by electrical stimulation of the pelvic nerve and subsequently tested for response to colorectal distension (CRD) and urinary bladder distension (UBD). Sixty-seven percent (n = 244) of the fibers were unmyelinated C-fibers and 33% (n = 120) were thinly myelinated A delta-fibers. 2. In three initial experiments, 35 fibers were identified by pelvic nerve stimulation and tested for response only to CRD; none of these fibers responded to CRD. In 20 subsequent experiments, 329 pelvic nerve afferent fibers were tested for response to CRD and UBD. Thirty-four percent (n = 112) of the 329 fibers were unresponsive to noxious CRD (80 mmHg) or to UBD (slow filling < or = 100 mmHg), 44% (n = 146) responded to UBD, 16% (n = 53) responded to CRD, and 6% (n = 18) responded to mechanical stimulation of the anal mucosa. 3. Of the total of 53 pelvic nerve afferent fibers that responded to CRD, 43 (81%) were C-fibers (mean: 1.5 m/s) and 10 (19%) were A delta-fibers (mean: 4.7 m/s). Fifteen of the CRD-sensitive fibers had no resting activity, whereas 38 fibers exhibited some resting activity (mean: 2.6 imp/s). 4. Reproducibility of responses to repeated CRD (80 mmHg, 30s, 10 trials at 4-min intervals) was tested in 17 fibers. In 16, responses to repeated distension were reproducible without evidence of facilitation or inhibition of subsequent responses. One fiber gave greater responses during the 9th and 10th trials. 5. Responses to graded CRD were studied in 44 fibers. All fibers exhibited monotonic, increasing stimulus-response functions < or = 80 mmHg of distension. Thresholds for response of the 44 fibers were determined after extrapolation of the least-squares linear-regression line to the ordinate and varied between 0 and 40 mmHg. Two populations of pelvic nerve afferent fibers in the colon were apparent: low threshold (LT) afferent fibers had a mean threshold of 2.9 mmHg (range: 0-10 mmHg; n = 34) and high threshold (HT) afferent fibers had a mean threshold of 32.6 mmHg (range: 28.0–40.0 mmHg; n = 10). 6. Chemosensitivity to bradykinin (BK) was tested in nine LT fibers. Seven fibers responded to BK (0.1 to 100 micrograms/kg ia) and two fibers did not respond up to 100 micrograms/kg of BK. Responses to BK tested in three fibers were dose dependent.(ABSTRACT TRUNCATED AT 400 WORDS)

The role of the pelvic nerve branches in the mediation of copulatory behavior was investigated. The somatomotor or the viscerocutaneous branch of the pelvic nerve was bilaterlly sectioned in sexually experienced male rats. Somatomotor branch surgery had no detectable effect. Viscerocutaneous branch transection altered copulatory parameters that reflect impairments in penile erection and seminal plug emission. The altered behavioral parameters approached or reached presurgical and sham values 21 days after transection, indicating that the damage to erectile and ejaculatory function was transient. It is suggested that animals with viscerocutaneous branch transection recover copulatory efficiency through a compensatory plastic mechanism, possibly involving the hypogastric nerve.

Injury to pelvic sympathetic and parasympathetic nerves from surgical and obstetrical trauma has long been cited as a cause for abnormal colorectal motility in humans. Using a rat model, acute transaction of these extrinsic nerves has been shown to effect colorectal motility. The aim of this study is to determine in a rat model how transection of these extrinsic nerves affects colonic transit over time.Eighty-two Sprague-Dawley rats underwent placement of a tunneled catheter into the proximal colon. Bilateral hypogastric, pelvic nerves (HGN and PN) or both were transected in 66 rats. The remaining 16 rats received a sham operation. Colonic transit was evaluated at postoperative days (PODs) 1, 3, and 7 by injecting and calculating the geometric center (GC) of the distribution of (51)Cr after 3 h of propagation.At POD 1, transection of PNs significantly delayed colonic transit (GC = 4.9, p0.05), while transection of HGNs (GC = 8.5, p0.05) or transection of both nerves (GC = 7.8, p0.05) significantly accelerated colonic transit, when compared with sham operation (GC = 6.0). A significant trend toward recovery was noted in both the HGN and PN transection groups at POD 7.Damage to the extrinsic sympathetic and/or parasympathetic PNs affects colonic transit acutely. These changes in large bowel motor function normalize over time implicating a compensatory mechanism within the bowel itself.

This study aims to report pelvic nerve damage secondary to surgical treatment of pelvic organ prolapse and the role of laparoscopy in the diagnosis and treatment of such nerve damage.Ninety-five consecutive patients complaining of pain and/or bladder or bowel dysfunction following surgery for pelvic prolapse underwent laparoscopic exploration for pelvic neuropathy.A mean reduction in visual analog score (VAS) from 8.9 (± 0.96; 6-10) preoperatively to 2.9 (± 2.77; 0-6) at 1-year follow-up was obtained in patients after laparoscopic nerve decompression (n = 90; p0.001). Success, defined as a reduction in VAS score of greater than 50%, was obtained in 84% of patients. Sixty-five patients (68%) discontinued the regular use of analgesics.Because secondary nerve damage can appear months or years after the primary procedure, long-term follow-up is mandatory and should focus on nerve damage as well as anatomical and functional outcomes. Laparoscopy is a unique method for etiologic diagnosis and neurosurgical treatment of such nerve lesions through decompression or implantation of an electrode for neuromodulation.

Detailed micturitional histories and urodynamic studies were conducted to investigate the micturitional disturbance in multiple system atrophy (MSA). Eighty-six patients with MSA comprised of 14 with striatonigral degeneration (SND), 42 with olivopontocerebellar atrophy (OPCA) and 30 with Shy-Drager syndrome (SDS). The results were as follows. Micturitional symptoms were noted in over 90% of patients with each type of MSA. Dominant symptoms were irritative ones in SND and OPCA, and a combination of irritative and obstructive ones in SDS. Micturitional symptoms in SDS appeared earlier than those in SND or OPCA. The degree of micturitional disturbance was severer in SDS than in SND or OPCA. Micturitional disturbance tended to become worse as the disease progressed. The responsible sites of lesions of micturitional disturbance seemed to be supra- as well as infranuclear lesions of the pelvic and pudendal nerves in MSA. Infranuclear lesions were more prominent in SDS than in SND or OPCA. Follow-up studies of some of the patients with SDS and OPCA suggested that the responsible sites of pelvic nerve lesions changed from supra- to infranuclear lesions during the course of disease.

BACKGROUND: Defects of the pelvic nerve innervation of levator ani muscle are associated with poor postoperative anorectal function in patients with anorectal malformation (ARM). We have previously shown deficient development of motoneurons innervating the levator ani muscle in rats with ARM. In this study we investigate whether there is a deficiency in the development of sensory neurons that innervate the levator ani muscle in rats with ARM. METHODS: ARM was induced by ethylenethiourea (ETU) in fetal rats. Retrograde tracer fluorogold (FG) was injected into the levator ani muscle. Serial transverse sections encompassing the entire length of the lumbosacral spinal cord were examined. The number of FG-labeled sensory neurons was scored and compared between fetuses with ARM and normal fetuses. RESULTS: The number of FG-labeled sensory neurons innervating the levator ani muscle in normal control fetuses, ETU-fed fetuses with no malformation, low type of imperforate anus, high type of imperforate anus, and high type of imperforate anus combined with neural tube defects were determined to be (mean ± SEM) 11,804 ± 2362, 10,429 ± 1708, 2886 ± 705, 1026 ± 425, and 964 ± 445, respectively. FG-labeled sensory neurons in fetuses with imperforate anus with or without neural tube defects were significantly fewer than in control and ETU-fed fetuses without malformation (p < 0.05). CONCLUSIONS: Defective sensory neurons innervating the levator ani muscle is a primary anomaly that coexists with the alimentary tract anomaly in ARM during fetal development. Nerve innervation deficiency of the pelvic muscles contributes to the poor postoperative anorectal functions in ARM patients. Birth Defects Research (Part A), 2009. © 2009 Wiley-Liss, Inc.

Background The exact mechanisms of action of intravesical electrical stimulation (IVES) are not yet fully understood. Objective To gain more insight into the underlying mechanism(s) of the direct detrusor response during IVES by transsecting the dorsal roots and the pelvic nerve consecutively at different levels and to determine whether the efficiency of IVES to induce contraction could be enhanced by simultaneous bladder filling and IVES and by changing the bladder-filling grade. Design, Setting, and Participants Eighteen Sprague-Dawley rats underwent IVES (square-wave pulses at 10 Hz, 20-ms pulse duration). Measurements In seven rats, IVES-induced bladder-pressure development was studied after the bladder nerves were consecutively sectioned bilaterally at four different levels: no lesion, L6 dorsal roots, L6 ventral roots, pelvic nerve, and major pelvic ganglion with surrounding nerves. Bladder-pressure development induced by IVES with simultaneous bladder filling, by bladder filling alone, and by IVES alone was recorded in seven other rats, and bladder-pressure development induced by IVES with different grades of bladder filling was recorded in four rats. Results and Limitations Contraction during IVES was significantly weaker after consecutive section of more nerves (all p < 0.001), but a small contraction (19 ± 17% of baseline) could be elicited even after total decentralization. In the neurologically intact rats, separate stimulation and bladder filling gave contraction strengths similar to those of simultaneous bladder filling and stimulation, but the latter gave contraction after a significantly shorter stimulation time (both p < 0.015). Conclusions IVES-induced contraction is, for the major part, a nerve-mediated process. However, a small bladder-pressure rise was induced by direct bladder-wall stimulation after all nerves were cut. Simultaneous electrical stimulation and bladder filling needed much shorter stimulation times than bladder filling alone or stimulation alone. If confirmed in humans, this could shorten IVES sessions substantially without altering the contractile results and could indicate that summation of afferent potentials from different triggers is possible.

Electrical stimulation (20–35 Hz, 2–5 V, 1.5 h) of the pelvic nerve in urethane-anesthetized rats increased the expression of c-fos protein-immunoreactivity primarily in neurons in the L6–S1 segements of the spinal cord. The neurons were localized to areas receiving afferent input from the pelvic viscera including the superficial dorsal horn, the dorsal commissure, and lateral laminae V–VII in the region of the sacral parasympathetic nucleus. These experiments indicate that (1) electrical stimulation of abdominal nerves following surgical exposure is a useful method for tracing visceral afferent pathways and (2) afferent information from the pelvic viscera is received by neurons in specific areas of the dorsal horn.

In 69 dogs with divided hypogastric nerves anesthetized with ketamine and chloralose the outflows of the pelvic vesical branch (PV) and pudendal urethral branch (PU) were recorded, and effects of amygdaloid and olfactory tubercle stimulation on them were studied. Stimulation (2-100 Hz, 3 ms, 0.2 mA) was applied to the amygdaloid body and olfactory tubercle. When the bladder contraction was induced by amygdaloid stimulation, the increased PV and decreased PU appeared after latencies of about 115 and 110 ms, respectively. When the bladder relaxation was, oppositely, elicited by stimulation, the decreased PV and enhanced PU occurred after latencies of 110 and 90 ms, respectively. The PV excitation was elicited by medial parts of the intermediate principal nucleus, medial parts of the medial principal nucleus, a part of cortical nucleus and of pericortical nucleus. Inhibition of PV was induced by lateral parts of the medial principal nucleus, medial nucleus, central nucleus and a part of the pericortical nucleus. Olfactory tubercle stimulation elicited PV excitation and PU inhibition with latencies of about 100 ms. The vesicopressor response from the tubercle was not abolished by section of the medial preoptic area, medial hypothalamus and periaqueductal gray, but was abolished by added section of the lateral preoptic area, lateral hypothalamus and lateral mesencephalic tegmentum. At the rostral pontine level, the response was abolished by partial section of the lateral part of the pontine reticular formation ipsilateral to the stimulation.

骨盤神経を介して, 骨盤内臓を支配する交感神経と陰部神経, 坐骨神経, 脛骨神経, 総腓骨神経を介して四肢体幹を支配する交感神経の中に起始細胞を同じくする神経が在るやいなやを標識部位の異なる二種類の螢光色素を用い検討した。その結果, 両神経に対する主要分節であるL7-S2 (3) 幹神経節の間で, 二重標識細胞の存在が認められた。その割合は骨盤内臓を支配する節後細胞の平均約0.73%であった。このような二重標識細胞の存在は, 鍼灸作用の構造を考察する上で, 自律神経が末梢の神経節でも遠隔部や四肢体幹の統合, 拡散, 収束等の場になり得る可能性を示唆するものである。

We recently reported that neurons in the sacral parasympathetic nucleus (SPN) project directly to the hypothalamus. In the present study, we examined the possibility that individual neurons in SPN send both an axon into the pelvic nerve and an ascending projection to the hypothalamus. We used a new double-labeling technique in which two sensitive retrograde tracers (Fluoro-gold and cholera toxin subunit B immunocytochemically stained with rhodamine-labeled antibodies) were combined. The effectiveness of this combination for singly and doubly labeling neurons was established in experiments in which both tracers were injected into overlapping areas of the tongue or ventrobasal thalamus. These injections doubly labeled large numbers of neurons in the hypoglossal or dorsal column nuclei, respectively. In studies of the projections of neurons in the SPN, injection of one tracer into the hypothalamus and the other into the pelvic nerve and/or pelvic ganglion singly labeled many neurons (more than 3300 in the 7 examined cases). However, no SPN neurons were doubly labeled. These findings indicate that the SPN in the rat consists of at least two distinct groups of cells, parasympathetic preganglionic neurons and neurons that project to the hypothalamus.

Cerebral evoked potentials (EPs) were recorded in 25 neurologically normal subjects aged 22–73 years (mean 44.0) after stimulation of the posterior urethra (PU) and the pudendal nerve. After maximal PU stimulation 2 different configurations of the potential were found. In 12 cases a simple bi-triphasic wave form was recorded while in 12 cases there was a bifid form of the first negative wave. In 1 case identical EPs were recorded after PU and pudendal nerve stimulation. It was concluded that (1) PU stimulation excites fibres in the pudendal nerve at higher stimulation strength, resulting in a bifid wave form of the cerebral evoked potential in some individuals, (2) the most prominent negative peak, N1, with a latency of 102.1 ± 13.2 msec, is the most reproducible part of the PU-evoked potential, (3) the N1 is probably transmitted through Aδ fibres localized in the pelvic nerves, (4) there are differences between individuals concerning pudendal and pelvic nerve involvement in afferent innervation of the urethra.

Obturator nerve neuropathies after tension-free vaginal tape or transobturator tape are considered to be caused by nerve trauma, although it is unclear whether these are accidents or whether these injuries are inherent to the procedure of tape insertion. Two cases show that obturator nerve neuropathy can occur after tension-free vaginal tape without direct trauma to the obturator nerve possibly as a consequence of excessive fibrotic reaction or persisting low-grade inflammation. PubMed Entrez, Cochrane Library, and up-to-date databases were searched for obturator and pudendal neuropathy and for neuropathies associated with tension-free vaginal tape-transobturator tape and the symptoms, diagnosis, and therapy of the pudendal and obturator nerve neuropathies are reviewed. Based on data, our experience, and data available in literature, we can conclude that, if conservative obturator nerve block confirms the diagnosis of obturator nerve neuropathy and symptoms recur shortly thereafter, a laparoscopic neurolysis can be proposed as therapy.

The effect of bethanechol, a muscarinic agonist, was studied by cystometrography in conscious rats with bilateral pelvic nerve (PN) lesions. In sham-operated rats, the transvesical infusion of saline elicited regularly micturition. The micturition was abolished by the bilateral PN transection, resulting in overflow incontinence. Bethanechol (30 mg/kg), administered orally to denervated rats, significantly increased the micturition frequency. Therefore, the micturition seems to be largely dependent upon muscarinic receptors of the bladder, and the finding supports the clinical effect of bethanechol. Moreover, this animal model may be useful for studying the overflow incontinence from detrusor failure of neuropathic origin.

Although restraint stress accelerates colonic transit via a central corticotropin-releasing factor (CRF), the precise mechanism still remains unclear. We tested the hypothesis that restraint stress and central CRF stimulate colonic motility and transit via a vagal pathway and 5-HT3 receptors of the proximal colon in rats. 51Cr was injected via the catheter positioned in the proximal colon to measure colonic transit. The rats were subjected to a restraint stress for 90 min or received intracisternal injection of CRF. Ninety minutes after the administration of 51Cr, the entire colon was removed, and the geometric center (GC) was calculated. Four force transducers were sutured on the proximal, mid, and distal colon to record colonic motility. Restraint stress accelerated colonic transit (GC of 6.7 ± 0.4, n = 6) compared with nonrestraint controls (GC of 5.1 ± 0.2, n = 6). Intracisternal injection of CRF (1.0 μg) also accelerated colonic transit (GC of 7.0 ± 0.2, n = 6) compared with saline-injected group (GC of 4.6 ± 0.5, n = 6). Restraint stress-induced acceleration of colonic transit was reduced by perivagal capsaicin treatment. Intracisternal injection of CRF antagonists (10 μg astressin) abolished restraint stress-induced acceleration of colonic transit. Stimulated colonic transit and motility induced by restraint stress and CRF were significantly reduced by the intraluminal administration of 5-HT3 antagonist ondansetron (5 × 10−6 M; 1 ml) into the proximal colon. Restraint stress and intracisternal injection of CRF significantly increased the luminal content of 5-HT of the proximal colon. It is suggested that restraint stress stimulates colonic motility via central CRF and peripheral 5-HT3 receptors in conscious rats.

Single medullary reticular formation (MRF) neurons receive multiple somatovisceral convergent inputs originating from many different spinal and cranial nerves, including the pelvic nerve (PN), dorsal nerve of the penis (DNP), and the abdominal branches of the vagus. In a previous study, the input to MRF from the male genitalia was shown to be eliminated with chronic 30-day dorsal hemisection at the T8 spinal level. In this study, the effect of a smaller chronic lesion [dorsal column lesion (DCx)] on MRF neuronal responses was examined. Responses to bilateral electrical stimulation of the DNP remained. MRF neuronal responses to non-noxious (touch/stroke) levels of penile stimulation, however, were eliminated; only responses to noxious pinch remained. No differences were found for the number of neurons responding to noxious distention of the colon between the DCx and control groups. Although no differences were found across these groups for the percent MRF responses to vagal stimulation, the mean response latency for the DCx group was twice the sham-DCx/intact control group. Taken together, these results indicate that the MRF receives at least some of its input from the male genitalia via pathways located within the dorsal columns at the mid-thoracic spinal level.

Reflex plasticity between pelvic afferent and pudendal efferent nerve fibers was examined in anesthetized rats. Brief high-frequency electric stimulation (300 pulses at 100 Hz) of the pelvic nerve afferent fiber produced a long-lasting potentiation of the pelvic-to-pudendal reflex (PPR). This tetanization-induced potentiation was abolished by a selective N-methyl-d-aspartate (NMDA) receptor antagonist and attenuated by a non-NMDA excitatory amino acid receptor antagonist. However, the GABAA-receptor antagonist had no effect on this potentiation. Both intrathecal glutamate (0.1 mM, 2–5 μl it) and NMDA (0.1 mM, 2–5 μl it) induced a potentiation of PPR similar to that of tetanization. Agonist-induced potentiation was shorter than tetanization-induced potentiation. The duration of the contraction wave of intraurethral pressure, elicited by PPR, was elongated by tetanization-induced potentiation, whereas the peak pressure was not affected. All these results demonstrate that brief high-frequency stimulation of the pelvic nerve afferent fiber can induce a distinct and long-lasting modulation in PPR activity and this change may be involved in nociceptive C afferent-induced obstructive urinary dysfunctions.

Although the guinea pig is used widely in experimental medical research, including in studies on micturition control, the spinal origin of preganglionic parasympathetic bladder and somatic external urethral sphincter motoneurons is not known. In the male, guinea pig using wheat germ agglutinin-conjugated horseradish peroxidase and dextran Alexa Fluor((C)) 488/568 tracers, preganglionic parasympathetic bladder motoneurons were observed in the ventrolateral part of the intermediolateral cell group of the first sacral segment. The external urethral sphincter motoneurons were found to be located in the ventral horn of the first sacral segment, in a cell group corresponding with the nucleus of Onuf in cat and human. (C) 2004 Elsevier Ireland Ltd. All rights reserved.

The authors report a case of voiding dysfunction with reduced sensation and areflexia 13 months after a repeat LUNA due to pelvic nerve injury. Anatomic distortion and increased vascularity were likely contributing factors. Repeat procedures may expose patients to a risk of such injury due to anatomic distortion.

The relaxation of the smooth muscle in the vagina and clitoris and the increase of blood flow into these organs is thought to be essential in the female sexual response. Vardenafil is a type 5 phosphodiesterase (PDE5) inhibitor that potentiates the nitric oxide (NO)/cGMP pathway facilitating penile smooth muscle relaxation and improving penile erection in men. Although the potentiation of the NO/cGMP pathway through PDE5 inhibitors can clearly enhance blood flow into the penis and is used in the therapy of male sexual dysfunction, there is controversy about the efficacy of these agents in improving female sexual function. The aim of this work was to evaluate the effects of vardenafil on the increase of blood flow into the vagina and clitoris induced by pelvic nerve electrical stimulation (PNES) in a female dog model. Application of PNES produced consistent and frequency-related increased blood flow into the vagina and clitoris of anesthetized female dogs. The magnitude and duration of the blood flow responses to PNES were variable among the different animals but remained stable over time within the same animal. The intravenous administration of vardenafil (1 mg/kg) significantly potentiated the increases in blood flow produced by PNES into the vagina (381.4 and 206.2% of control response at 5 and 10 Hz, respectively, P0.01, n=6) and clitoris (379.4 and 238.5% of control response at 5 and 10 Hz, respectively, P0.01, n=6) 20 min after administration. The significant enhancement of PNES-induced responses was maintained 50 min (224.5 and 181.0%, P0.01 in vagina; 294.8 and 258.9%, P0.05 in clitoris) and 80 min after vardenafil administration (209.5 and 156.9%, P0.05 in vagina; 268.9 and 194.9%, P0.05 in clitoris). Here we present a feasible model for research into female sexual function. Our results show that vardenafil effectively potentiates the blood flow responses to PNES in the genitalia of female dogs. These results emphasize the role of the NO/cGMP pathway in the local vasodilatory response in female sexual organs and provide a rationale for testing PDE5 inhibitors, such as vardenafil, as a treatment for certain forms of female sexual dysfunction.

Intravesical oxybutynin is used to control bladder overactivity in patients who are refractory to or cannot tolerate oxybutynin given orally. Although it is clinically effective, the mode of action of intravesical oxybutynin remains unclear. We tested the influence of intravesical oxybutynin on single fiber pelvic nerve afferents from the rat bladder.A total of 15 single afferent bladder units were identified. Based on conduction velocity they were grouped as Adelta or C fibers. The effect of repeat bladder filling was studied on the mechanosensitive properties of these units. Oxybutynin was than instilled and left in the bladder for 15 minutes. Unitary afferent activity was again analyzed 15, 60 and 90 minutes after the drug was removed.Repeat bladder filling did not change nerve activity in Adelta or C fibers. At 15 minutes after oxybutynin was washed out of the bladder C fiber afferents responded significantly less to intravesical pressure and volume compared with control filling. At 60 minutes C fibers partly regained mechanosensivity. After 90 minutes sensitivity still increased without achieving the response level before oxybutynin. No significant changes were noted in Adelta fibers during repeat bladder filling or after oxybutynin instillation.In this study we showed that intravesical oxybutynin has a direct anesthetic effect within the bladder wall. It temporarily desensitizes C fiber afferents, which could explain its clinical benefits in decreasing symptoms of bladder overactivity. No measurable effect was found on Adelta fibers.

When recording electrical signals from a whole nerve, an increase in the firing frequencies of the fibers contained in the nerve causes an increase in the rectified and time-averaged recorded signal. The latter thus represents superimposed neural activity and can be used for detecting changes in the recorded afferent and/or efferent nerve traffic. The possibility of detecting a fast bladder pressure increase from an increase in the recorded pelvic nerve afferent activity was investigated in this study. Two signal processing approaches were compared: simple discriminant-window thresholding and cumulative sum (CUSUM) algorithm. Both are shown to be able to detect a sudden rise in bladder pressure with the adaptive CUSUM-algorithm being more reliable, but slower.

The objectives of this work were to evaluate the contributions of the ancillary penile nerves to penile erection in male rats in vivo. We investigated the effects of unilateral and bilateral transection of the cavernous nerve (main penile nerve) on the increase in intracavernous pressure (ICP) following electrical stimulation of the medial preoptic area (MPOA) in male rats in vivo. After unilateral or bilateral transection of the cavernous nerve (main penile nerve), the ICP responses showed decreases of 28% and 55%, respectively compared to those ICP responses before transection. In other words, even after bilateral transection of the cavernous nerve, significant increases in the ICP response following central stimulation were observed. In contrast to these findings, the ICP response was completely eliminated following bilateral pelvic nerve transection. These data suggested that the ancillary penile nerves, which originate from the major pelvic ganglia, have a complementary role to the cavernous nerves in the autonomic motor innervation of the penis.

Information is lacking from prospective studies on the incidence and risk factors for postoperative nerve injury after routine gynecologic surgery. In 2 retrospective studies, the reported risk of nerve injury from major gynecologic oncologic procedures was estimated to be between 1.1 % and 1.9%. This prospective cohort study evaluated the overall incidence and time course of pelvic nerve injury in a population of 616 female patients undergoing elective gynecologic surgery for benign and malignant conditions. The study was conducted between 2007 and 2008 at a single academic medical center. Before surgery, neurologic evaluation found preexisting lower extremity neuropathies in 12 (1.9%) participants. After surgery, 14 new peripheral nerve injuries were observed in 11 patients; the overall incidence of postoperative neuropathy was 1.8% (11/616), with a 95% confidence interval of (1.0-3.2). The neuropathies detected included 1 ilioinguinal/ iliohypogastric, 1 saphenous, 1 genitofemoral, 1 common fibular, 5 lateral femoral cutaneous, and 5 femoral. There was a complete resolution of neuropathic symptoms in 91% (10/11) of the patients at a median time of 31.5 days (range: 1 day to 6 months). These findings are consistent with other studies suggesting a low risk of new onset neurologic injury after gynecologic surgery.