Parasympathetic Pelvic Nerves Research Articles

Advanced Neural Interface toward Bioelectronic Medicine Enabled by Micro-Patterned Shape Memory Polymer.

Recently, methods for the treatment of chronic diseases and disorders through the modulation of peripheral and autonomic nerves have been proposed. To investigate various treatment methods and results, experiments are being conducted on animals such as rabbits and rat. However the diameter of the targeted nerves is small (several hundred μm) and it is difficult to modulate small nerves. Therefore, a neural interface that is stable, easy to implant into small nerves, and is biocompatible is required. Here, to develop an advanced neural interface, a thiol-ene/acrylate-based shape memory polymer (SMP) was fabricated with a double clip design. This micro-patterned design is able to be implanted on a small branch of the sciatic nerve, as well as the parasympathetic pelvic nerve, using the shape memory effect (SME) near body temperature. Additionally, the IrO2 coated neural interface was implanted on the common peroneal nerve in order to perform electrical stimulation and electroneurography (ENG) recording. The results demonstrate that the proposed neural interface can be used for the modulation of the peripheral nerve, including the autonomic nerve, towards bioelectronic medicine.

Roles of the noradrenergic nucleus locus coeruleus and dopaminergic nucleus A11 region as supraspinal defecation centers in rats.

We previously demonstrated that administration of norepinephrine, dopamine, and serotonin into the lumbosacral defecation center caused propulsive contractions of the colorectum. It is known that the monoamines in the spinal cord are released mainly from descending neurons in the brainstem. In fact, stimulation of the medullary raphe nuclei, the origin of descending serotonergic neurons, enhances colorectal motility via the lumbosacral defecation center. Therefore, the purpose of this study was to examine the roles of the noradrenergic nucleus locus coeruleus (LC) and dopaminergic nucleus A11 region in the defecation reflex. Colorectal motility was measured with a balloon in anesthetized rats. Electrical stimulation of the LC and A11 region increased colorectal pressure only when a GABAA receptor antagonist was injected into the lumbosacral spinal cord. The effects of the LC stimulation and A11 region stimulation on colorectal motility were inhibited by antagonists of α1-adrenoceptors and D2-like dopamine receptors injected into the lumbosacral spinal cord, respectively. Spinal injection of a norepinephrine-dopamine reuptake inhibitor augmented the colokinetic effect of LC stimulation. The effect of stimulation of each nucleus was abolished by surgical severing of the parasympathetic pelvic nerves. Our findings demonstrate that activation of descending noradrenergic neurons from the LC and descending dopaminergic neurons from the A11 region causes enhancement of colorectal motility via the lumbosacral defecation center. The present study provides a novel concept that the brainstem monoaminergic nuclei play a role as supraspinal defecation centers.NEW & NOTEWORTHY The present study demonstrates that electrical and chemical stimulations of the locus coeruleus or A11 region augment contractions of the colorectum. The effects of locus coeruleus and A11 stimulations on colorectal motility are due to activation of α1-adrenoceptors and D2-like dopamine receptors in the lumbosacral defecation center, respectively. The present study provides a novel concept that the brainstem monoaminergic nuclei play a role as supraspinal defecation centers.

Robotic-assisted laparoscopic ureteral re-implant (RALUR): Can post-operative urinary retention be predicted?

Urinary retention following robotic-assisted laparoscopic extravesical ureteral reimplantation (RALUR) is proposed to be due to traction or injury of the pelvic parasympathetic nerve plexus during distal ureteral dissection. Nerve-sparing techniques have been employed to avoid injury to the pelvic plexus, either directly or indirectly. This single-center study assessed postoperative urinary retention rates after extravesical RALUR and investigated whether demographic or operative factors could predict this occurrence. All RALUR cases entered into an Institutional Review Board-approved registry were retrospectively reviewed, and the rate of postoperative retention was determined. Postoperative urinary retention was defined as the need for catheterization at any time in the postoperative period during hospital admission or within 1 week after the operation. This included acute urinary retention episodes (AUR) as well as high post-void residuals (>50% of expected bladder capacity). Univariate analysis was performed to analyze for predictors of postoperative retention. Factors assessed included age, gender, clinical presentation, bowel bladder dysfunction (BBD), pre-operative urinary tract infection (UTI), procedure length, grade of vesicoureteral reflux (VUR), and operative laterality. A total of 128 patients underwent extravesical RALUR in 179 ureters during the study period 2012-2016. Male:female ratio was 1:2.6. Median age at surgery was 4 years. Bilateral RALUR was performed in 52 cases (40.6%), and unilateral in 76 (59.4%). Urinary retention requiring catheterization occurred in 11 cases (8.59%). Of these, seven were post-bilateral RALUR, while the remaining four were unilateral. In seven cases, postoperative retention occurred within 24h following RALUR. The remaining four instances occurred within 1 week, despite successful voiding in the immediate postoperative period. Univariate analysis revealed male gender (P=0.009) and operating room time (P=0.029) as predictors of retention. No association was found with age, weight, BBD, pre-operative UTI, grade of VUR, or laterality. Urinary retention after RALUR was an infrequent complication. When it did occur, urinary retention appeared to be secondary to covariates such as male gender and length of surgical time - possibly an indication of technical difficulty - rather than laterality of repair.

The effects of FK1706 on nerve regeneration and bladder function recovery following an end-to-side neurorrhaphy in rats.

BackgroundImmunophilin ligands are neuroregenerative agents binding to FK506 binding proteins, by which stimulate recovery of neurons in a variety of injury nerves. FK1706 is a novel immunophilin ligand which has neuroprotective and neuroregenerative effects but without immunosuppressive activity. At present, most reports about FK1706 in ameliorating nerve injury and functional recovery are limited to cavernous nerve injury and erectile function recovery. This study aimed to demonstrate the effects of FK1706 on nerve regeneration and bladder function recovery following an end-to-side neurorrhaphy in rat models.MethodThe numbers of regenerated myelinated axons of the pelvic parasympathetic nerve (PPN) in the three groups’ rats (FK1706 + ETS, ETS and control groups) were evaluated. Their intravesical pressure (IVP), S100β and growth associated protein 43 (GAP43) expressions were also compared.ResultsIn FK1706 + ETS group, 90% the rats showed that the frequency of FG labeled neurons was larger than the 3.5 cutoff value, 100% the rats showed that the frequency of FG-FB double-labeled neurons was larger than the 5.5 cutoff value. The average maximum of IVP in FK1706 + ETS group reached 76.3% of the value in control group. Their average number of myelinated axons of regenerated PPN reached 80% of the amount in control group. The nerve regeneration-associated markers data indicated that the expression level of S100β and GAP43 in FK1706 + ETS group was approximately 2-fold higher than that of ETS group (P < 0.05).ConclusionsAfter end-to-side neurorrhaphy, FK1706 effectively enhanced the nerve regeneration and bladder function recovery.

Effect of FK1706 on nerve regeneration after end-to-side neurorrhaphy of autonomic nerve and somatic nerve in rats

Objective To evaluate the effect of FK1706 on nerve regeneration after end-to-side (ETS) neurorrhaphy of autonomic nerve and somatic nerve in rats through morphological observation. Methods Thirty rats were randomly divided into three groups in terms of different treatments (n=10 in each group). In FK1706 group, the left L6 ventral root (L6VR) and L4 ventral root (L4VR) of rats were sutured in an ETS fashion and FK1706 (0.3 mg/kg) was administrated subcutaneously for 5 consecutive days per week for a total of 8 weeks after ETS neurorrhaphy. In ETS group, the same operation as FK1706 group was performed but without FK1706 applied after surgery. In control group, left L6 dorsal root (L6DR), S1 ventral root (S1VR) and S1 dorsal root (S1DR) were transected but the left L6VR was preserved as normal control. After 4 months, the left pelvic parasympathetic nerve (PPN) to which L6VR extended was harvested for semithin and ultrathin sections in FK1706 and ETS groups to count the number of myelinated axons. The number and morphology of myelinated axons and thickness of myelin sheath were compared between the two groups. Results After 4 months, the morphology of the regenerated L6VR distal to the neurorrhaphy site in FK1706 and ETS groups was normal. The number of regenerated myelinated axons of PPN was 515.6±43.3 and 328.4±46.4 in FK1706 and ETS groups, respectively (P=0.000). The thickness of myelin sheath of regenerated PPN was (0.672 4±0.110 1) μm and (0.466 8±0.076 3) μm in FK1706 and ETS groups, respectively (P=0.000). Conclusion The effect of autonomic nerve regeneration could be enhanced after ETS neurorrhaphy of autonomic nerve and somatic nerve through FK1706, which could improve rehabilitation of nerve injury. Key words: FK1706; Nerve regeneration; Autonomic nerve; Somatic nerve; End-to-side neurorrhaphy

Exogenous serotonin regulates colorectal motility via the 5-HT2 and 5-HT3 receptors in the spinal cord of rats.

We previously reported that intrathecal injection of noradrenaline or dopamine causes enhancement of colorectal motility. As these monoamines are neurotransmitters of descending pain inhibitory pathways in the spinal cord, we hypothesized that serotonin, which is one of the neurotransmitters involved in descending pain inhibition, also influences the lumbosacral defecation center. Therefore, we examined whether serotonin acting on the spinal defecation center enhances colorectal motility. Colorectal intraluminal pressure and propelled liquid volume were recorded in vivo in anesthetized rats. Intrathecal injection of serotonin into the L6-S1 spinal cord elicited periodic increases in colorectal intraluminal pressure, being associated with increases in liquid output. Pharmacological experiments revealed that the effect of serotonin is mediated by both 5-HT2 and 5-HT3 receptors. The serotonin-induced enhancement of colorectal motility was unaffected even after disconnection of the defecation center from supraspinal regions by cutting the T8 spinal cord, while transection of the parasympathetic pelvic nerves prevented the colokinetic effect of serotonin. Finally, we investigated interactions among serotonin, noradrenaline and dopamine. Simultaneous administration of sub-effective doses of these monoamine neurotransmitters into the spinal cord caused propulsive colorectal motility slightly but substantially. These results demonstrate that exogenous serotonin acts on 5-HT2 and 5-HT3 receptors in the lumbosacral defecation center and activates the parasympathetic nervous system to enhance colorectal motility in cooperation with noradrenaline and dopamine.

Microbiota, the immune system, black moods and the brain—melancholia updated

There is now abundant evidence that the immune system and the brain have close functional interactions in both directions. This review focuses on the influence of the microbiota (the bacteria resident in the gut) on brain function in major depressive disorder (MDD) and related syndromes. The gut and the central nervous system communicate partly through the autonomic nervous system (ANS), consisting of the sympathetic (i.e., the splanchnic nerves) and the parasympathetic (i.e., the vagus nerve and the sacral parasympathetic pelvic nerves) nervous system. The brain integrates inputs from the digestive tract by a central autonomic network that includes the hypothalamus, limbic system and cerebral cortex with output to the ANS and hypothalamic-pituitary-adrenal gland (HPA) stress axis (Bonaz, 2013). There are also extensive chemical signaling systems via the blood.

Upregulation of mucosal 5‐HT3 receptors is involved in restoration of colonic transit after pelvic nerve transection

Colonic dysfunction occurs after pelvic autonomic nerve damage. The enteric nervous system can compensate. We investigated the role of mucosal serotonin receptors, 5-HT(3) and 5-HT(4) , in the colonic motility restoration over 2 weeks after parasympathetic pelvic nerve transection in a rat model. Male Sprague-Dawley rats underwent pelvic nerve transection or sham operation. Colonic transit was expressed as the geometric center of (51) Cr distribution. Mucosal 5-HT(3) and 5-HT(4) receptor expression was evaluated by Western blot. Intraluminal pressure increase was measured after 5-HT(3) (ondansetron) or 5-HT(4) receptor antagonist (GR125487) administration in vitro in sham and denervated distal colons. At 2 weeks, colonic transit in the denervated group was 30% slower compared to the sham group (P < 0.01). At 1 and 2 weeks, 5-HT(3) receptor expression was increased two-fold in the denervated group, compared to shams (P < 0.05). A three-fold smaller dose of ondansetron was required in denervated tissues to inhibit intraluminal pressure rise than in sham colons (P < 0.01). There was no difference in the expression of 5-HT(4) receptor or the response to GR125487 in denervated vs sham colons. Colonic motility was restored to approximately 70% normal over 1 week without further improvement at 2 weeks. Enteric nervous system compensated by upregulating mucosal 5-HT(3,) but not 5-HT(4,) receptors.

Recovery of colonic transit following extrinsic nerve damage in rats

Introduction. 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. Methods. 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 51Cr after 3 h of propagation. Results. At POD 1, transection of PNs significantly delayed colonic transit (GC = 4.9, p < 0.05), while transection of HGNs (GC = 8.5, p < 0.05) or transection of both nerves (GC = 7.8, p < 0.05) 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. Conclusions. 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.

The nerve regeneration after end-to-side nerve anastomosis of distal stump of autonomic nerve to somatic nerve in rats

Objective To observe the nerve regeneration after end-to-side anastomosis of distal stump of autonomic nerve to somatic nerve in rats. Methods Twenty-four Sprague-Dawley rats were divided into two groups: experimental group (n = 12) and control group (n = 12). In experimental group, rats had the left lumbar 6 ventral root (L6VR) transected in dura and the distal stump was sutured to the lateral face of left lumbar 4 ventral root (L4VR). In control group, rats had not been done any surgery. After 6 months, in experimental group, the nerves were intercepted 10 mm in length, from the proximal and distal end-to-side nerve anastomosis, regarded as donor nerve (L4VR) and recipient nerve (L%VR), and 10 mm from the pelvic parasympathetic nerve (PPN) and pudendal nerve (PN) from L6VR was intercepted, respectively. In control group, the corresponding nerves were harvested. The cross-sectional nerve slices were stained with toluidine blue through the use of histochemical technique, and the number of myelinated nerve fibers was counted. By comparing L6VR with L4VR the nerve passing rate was calculated, and the number of the nerve fibers of L6VR, PPN and PN between experimental group and control group was compared. Results The new myelinated nerve fibers were observed in the cross-sectional slices of the experimental rats. The number of the nerve fibers located in the L4VR, L6VR, PPN and PN was 1602. 2 ± 75.7,1037.9 ± 123.6, 817. 0 ±52. 2 and 510. 4 ± 29. 1, respectively. The nerve passing rate of the distal and the proximal ends from the anastomosis was 64. 8%, the ratio of the number of nerve fibers in L6VR, PPN and PN was 70.2%, 68.9% and 62.2%, respectively, between the experimental group and control group. Conclusion The somatic nerve can grow into and replace the autonomic nerve after the reflex pathway established by end-to-side anastomosis of autonomic nerve and somatic nerve in rats. Key words: End-to-side coaptation; Nerve regeneration; Somatic nerve; Autonomic nerve

Sympathetic and Parasympathetic Regulation of Rectal Motility in Rats

IntroductionThe colon and rectum are regulated by the autonomic nervous system (ANS). Abnormalities of the ANS are associated with diseases of the colon and rectum while its modulation is a putative mechanism for sacral nerve stimulation. The purpose of this study is to establish a rat model elucidating the role of the efferent ANS on rectal motility. Materials and MethodsRectal motility following transection or stimulation of parasympathetic pelvic nerves (PN) or sympathetic hypogastric nerves (HGN) was measured with rectal strain gauge transducers and quantified as a motility index (MI). Colonic transit was measured 24 hours after transection by calculating the geometric center (GC) of distribution of 51Cr Results and DiscussionTransection of PN and HGN decreased MI to 518 ± 185 g•s (p < 0.05) and increased MI to 5,029 ± 1,954 g•s (p < 0.05), respectively, compared to sham (975 ± 243 g•s). Sectioning of PN and HGN decreased transit with GC = 4.9±0.2 (p < 0.05) and increased transit with GC = 8.1±0.7 (p < 0.02), respectively, compared to sham (GC = 5.8 ± 0.3). Stimulation of PN and HGN increased MI to 831 ± 157% (p < 0.01) and decreased MI to 251 ± 24% (p < 0.05), respectively. ConclusionRectal motility is significantly altered by sectioning or stimulating either HGN or PN. This model may be useful in studying how sacral nerve stimulation exerts its effects and provide insight into the maladies of colonic motility.

Pathological changes of benign hyperplastic prostate after removal of innervation of cholinergic pelvic nerve: experiment with spontaneous hypertension rats

To study the pathological change of benign hyperplastic prostate after removal of the innervation of cholinergic parasympathetic pelvic nerve. Sixty-five male spontaneous hypertension rats (SHRs) were randomly assigned into 3 groups: operation group (n = 30) undergoing truncation of bilateral originating branches of parasympathetic pelvic nerve of major pelvic ganglion (MPG) followed by cystostomy, sham operation group (operation control group, n = 30) undergoing cystostomy, and normal control group (n = 5) not undergoing operation. 3, 7, 11, 15 and > or = 21 days after operation 6 rats from the 2 operation groups and 1 from the control group were sacrificed to observe the gross morphology and histological and cellular changes of the prostate glands. The prostate of the operation group on post-operational day 7 showed mild granular solidification and such change progressed gradually over time, the ratio of prostate wet weight/rat body weight was (0.4764 +/- 0.0125) mg/g on day 3, then gradually decreased, and became (0.2749 +/- 0.0197) mg/g > or = 21 days post-operationally; while the ratio of prostate tissue dry weight/wet weight on day 3 was (0.1966 +/- 0.0062), then gradually increased, and became (0.2596 +/- 0.0035) > or = 21 days post-operationally. HE staining showed that the glandular structure gradually became dilated and rounded, with accumulation of prostatic fluid. The glandular epithelial cells showed gradual degeneration, necrosis, and detachment. The glandular epithelium became progressively thinner, the smooth muscles elongated and thinned progressively, and the stromal components showed mild to moderate overgrowth. Electron microscopy showed that the glandular cells gradually underwent vacuolar degeneration and the structures of the basement membrane became fuzzy. The smooth muscle cells degenerated mildly, and the fibroblasts and collagenous fibers in the stroma overgrew slowly. All these histological changes were not found in the sham operation control and normal control groups. Remarkable atrophy occurs in benign hyperplastic prostatic gland after radical removal of the innervation of cholinergic parasympathetic pelvic nerve. Such operation may represent a novel therapy for BPH.

Pathophysiology of urinary dysfunction in multiple sclerosis

Bladder and urethra are innervated peripherally by pelvic parasympathetic, lumbar sympathetic and pudendal nerves; but a complex of brain networks is involved in the micturition cycle and the pontine micturition centre (PMC) has a fundamental role. Bladder storage is secondary to activation of β- and α-receptors with simultaneous inhibition of parasympathetic transmission and increased somatic discharges via the pudendal nerves. Bladder voiding involves coordination of sacral parasympathetic stimulation of the bladder, inhibition of sympathetic outflow and pudendal somatic outflow to the external striated sphincter. Lesions of the brain above the PMC are usually associated with detrusor overactivity; medullary lesions are characterised by urodynamic detrusor overactivity associated with detrusor-external sphincter dyssynergia. Sacral lesions can produce bladder areflexia and/or hypocontractility.

The LANN Technique to Reduce Postoperative Functional Morbidity in Laparoscopic Radical Pelvic Surgery

We investigated the feasibility and advantages of introducing Laparoscopic Neuro-Navigation (LANN) into the field of laparoscopic gynecologic radical pelvic surgery. In a prospective pilot study, 261 consecutive patients underwent laparoscopic radical pelvic surgery for cervical cancer or deep infiltrating endometriosis of the parametria. During the procedure, dissection and electrostimulation, and consequently, sparing of the pelvic parasympathetic nerves by transection of the parametria, were performed. Postoperative bladder dysfunction was documented. Laparoscopic dissection and electrostimulation of the pelvic splanchnic nerves were feasible in all patients without any complications, and the rate of postoperative bladder dysfunction was considerably reduced, to less than 1% of the patients. The parasympathetic nerve-sparing method using the Laparoscopic Neuro-Navigation technique in laparoscopic radical pelvic gynecologic surgery is a feasible and reproducible technique that preserves postoperative bladder function.

Colonic motility in the cat. IV. Peripheral pathways mediating the effects induced by hypothalamic and mesencephalic stimulation.

Rostad, H. Colonic motility in the cat. IV. Peripheral pathways mediating the effects induced by hypothalamic and mesencephalic stimulation. Acta physiol. scand. 1973. 89. 154–168. The peripheral pathways by which the hypothalamus and mesencephalon influence the motility of the colon have been studied by combining brain stimulation and peripheral nerve sectioning, and by use of autonomic blocking agents. Excitatory colonic effects induced from the hypothalamic sympatho-inhibitory area with concomitant blood pressure falls were found to be mediated through the sympathetic lumbar colonic nerves, whereas excitatory responses with associated blood pressure rises were conveyed through the latter as well as through the parasympathetic pelvic nerves. On the other hand, the augmentatory colonic effects usually associated with blood pressure rise evoked from the mesencephalon were conveyed through the lumbar colonic nerves only. The responses through the lumbar colonic and pelvic nerves were blocked by guanethidine and atropine, respectively. The augmentatory colonic responses from the hypothalamic sympatho-inhibitory area were blocked by the beta-adrenergic blocking agent propranolol, whereas the effects from the other responsive hypothalamic areas, transmitted through the lumbar colonic nerves, were blocked by alpha-blocker (phenoxybenzaminc), but not by propranolol. This finding support the presence of alpha-excitatory receptors in the colonic wall. Inhibition of colonic motility induced by hypothalamic and mesencephalic stimulation, weir found to be mediated through the lumbar colonic as well as through the splanchnic nerves. The effects were blocked by guanethidine, and those from the responsive hypothalamic zones were also blocked by propranolol.

Validity of Pelvic Autonomic Nerve Stimulation With Intraoperative Monitoring of Bladder Function Following Total Mesorectal Excision for Rectal Cancer

This prospective study was designed to clarify whether the results of the intraoperative stimulation of parasympathetic pelvic nerves performed in 31 patients after mesorectal excision for rectal carcinoma allowed predictions in terms of the postoperative bladder function of the patients. After monopolar stimulation of the splanchnic pelvic nerves using a constant voltage stimulator (Screener 3625), intravesical pressure increase was measured manometrically. The results were related to the postoperative residual urine volume, requirement of recatheterization and long-term catheterization, just as to the results of the validated International Prostatic Symptom Scores and the Quality of Life Index caused by urinary symptoms. The median follow-up period was nine (range, 2-14) months. Parasympathetic nerve stimulation was performed at 61 sites and results in intravesical pressure increase up to 6 cm water column in median. In 11 patients (33.3 percent), a negative test result was achieved: 5 with unilateral and 6 with bilateral pressure increases of < or = 2 cm water column. Recatheterization was necessary in four patients, and all of them showed negative neuromonitoring results. Two of these patients were discharged with an in situ urinary bladder catheter. Postoperative increased residual urine volumes (> or =100 ml) resulted more frequently in the group with negative test results (63.6 vs. 21.1 percent; P = 0.047), and the International Prostatic Symptom Score and Quality of Life Index showed the worst results (9.9 +/- 6.7 vs. 3 +/- 4.9, P = 0.021; 2.4 +/- 1.7 vs. 0.7 +/- 1.3, P = 0.021). Intraoperative neurostimulation and manometric measurement of bladder pressure may contribute to the identification of parasympathetic pelvic nerves during total mesorectal excision. This method is suitable for intraoperative recording of nerve preservation and therefore associated with postoperative bladder function.

The Neuro-Urological Connection

Urine storage and micturition are tightly controlled by the peripheral and central nervous systems. The parasympathetic pelvic nerves mediate signals for voiding, whereas the sympathetic hypogastric and the somatic pudendal nerves mediate signals for urine storage. Glutamate is a key transmitter of the descending neuronal pathways during the storage phase of the micturition cycle. Its effects on the activity of the hypogastric and pudendal nerves are modulated by serotonin and/or noradrenaline. Duloxetine inhibits the neuronal uptake of serotonin and noradrenaline and thereby enhances their effects in the central nervous system including the spinal nuclei responsible for urine storage. Thus, in a bladder irritation model in anaesthetised cats duloxetine dose-dependently restored bladder capacity and enhanced activity of the external urethral sphincter/rhabdosphincter. Such effects should prove beneficial in the treatment of patients with stress urinary incontinence.

Delayed uterine re-inversion: A unique symptom complex

A case of late recurrence of uterine inversion is presented. Symptoms included constipation and urinary retention without uterine bleeding. Symptoms resolved 3 months after the replacement of the uterus. It is hypothesized that the symptoms were related to stretch injury to the pelvic parasympathetic nerves. Timely intervention may prevent long-term sequelae.

Intraoperative identification and neurophysiologic parameters to verify pelvic autonomic nerve function during total mesorectal excision for rectal cancer.

Preservation of parasympathetic and sympathetic nerves is required to avoid urogenital function disturbances after total mesorectal excision (TME) for rectal carcinoma. This study sought to determine whether intraoperative stimulation of parasympathetic nerves with monitoring of bladder contraction is useful in meeting this demand. In a prospective pilot study, 17 patients, 11 men and 6 women, underwent TME with pelvic autonomic nerve preservation performed by an experienced surgeon. The parasympathetic nerves were stimulated by an electrostimulation device (Screener 3625, Medronic), and the resulting bladder contraction was measured manometrically in all patients. Variations in pulse rate and voltage were measured to determine optimal stimulation parameters. A standardized questionnaire was used to record urogenital function disturbances. Residual urine volume was measured by ultrasound pre- and postoperatively. Shortterm outcomes data were evaluated to establish a possible association between intraoperative test results and postoperative bladder function. In 15 of 17 patients undergoing TME with pelvic autonomic nerve preservation for rectal carcinoma, the parasympathetic nerves were identified based on nerve stimulation-induced bladder contraction. Two patients with negative results on intraoperative nerve stimulation had persisting bladder dysfunction requiring an indwelling catheter after discharge from hospital. In spite of a short median followup of 2 months (range 1 to 4 months), in 7 of 10 men with intact erectile function prior to surgery, postoperative erectile dysfunction could be excluded. The study showed a pulse rate of 35 Hz and an electric potential of 12 V to be optimal stimulation parameters, associated with a mean intravesical pressure rise of 12.7 cm H(2)O (range 2.8 to 18.0 cm H(2)O). Intraoperative nerve stimulation with monitoring of intravesical pressure represents a technically simple procedure for the identification and verification of function of pelvic parasympathetic nerves during TME for rectal carcinoma.

A New Technique for Radical Hysterectomy with Emphasis on Preservation of Bladder Function

Bladder dysfunction always occurs, to varying degrees, following radical hysterectomy. In Japan, various techniques for preserving the pelvic autonomic nerves in a radical hysterectomy have been used to reduce the severity of bladder dysfunction. The authors describe a newly developed technique for preserving the pelvic autonomic nerves and present the post-operative urodynamic findings in cases in which this technique was used. Preservation techniques can be broadly classified into three types: preservation of the pelvic parasympathetic nerves, preservation of the pelvic sympathetic nerves, and preservation of the nerves to the bladder. In this new technique, as many of the pelvic parasympathetic nerves as possible are preserved when the cardinal ligament is cut. Then, the cardinal ligament is inserted into and pulled through the anterocranially located connective tissue in front of the pelvic plexus, which lies below the ureter. Finally, as many as possible of the vesical branching nerves are preserved ...