Impact of polypropylene prolapse mesh on vaginal smooth muscle in rhesus macaque

BACKGROUND

The use of polypropylene prolapse mesh to treat pelvic organ prolapse has been limited by mesh-related complications. Gynemesh PS mesh, implanted via sacrocolpopexy in rhesus macaques, had a negative impact on the vagina with thinning of vaginal muscularis and decreased vaginal smooth muscle contractility. The negative effect was attenuated when a bioscaffold derived from urinary bladder extracellular matrix was used as a composite with Gynemesh PS.

OBJECTIVE

The objective of the study was to further elucidate the impact of Gynemesh PS polypropylene mesh and MatriStem extracellular matrix bioscaffolds on the vaginal smooth muscle in terms of micromorphology of vaginal smooth muscle (muscle bundles and individual myocytes), innervation, and nerve-mediated contractile function following their implantations in a rhesus macaque model via sacrocolpopexy.

STUDY DESIGN

Thirty-two middle-aged rhesus macaques were randomized to undergo either a sham surgery (sham, n = 8), or the implantation of Gynemesh PS alone (n = 8) vs composite mesh comprised of Gynemesh PS plus 2-ply MatriStem (n = 8) vs 6-ply MatriStem alone (n = 8) via sacrocolpopexy. The graft-vagina complexes were harvested 3 months later. Histomorphometrics of smooth muscle bundles and myocytes were performed by immunofluorescent labeling of alpha smooth muscle actin, caveolin-3 (membrane protein), and cell nuclei followed by confocal imaging. The cross-sectional diameters of smooth muscle bundles and individual myocytes were quantified using images randomly taken in at least 5 areas of each section of sample. Contractile proteins alpha smooth muscle actin and smoothelin were quantified by Western immunoblotting. Nerve density was measured by immunohistochemical labeling of a pan-neuron marker, PGP9.5. Nerve-mediated smooth muscle contractility was quantified using electrical field stimulation. One-way analysis of variance and appropriate post hoc tests were used for statistical comparisons.

RESULTS

Compared with sham, the implantation of Gynemesh PS alone resulted in a disorganized smooth muscle morphology with the number of small muscle bundles (cross-sectional diameter less than 20 μm) increased 67% (P = .004) and the myocyte diameter decreased 22% (P < .001). Levels of contractile proteins were all decreased vs sham with alpha smooth muscle actin decreased by 68% (P = .009), low-molecular-weight smoothelin by 51% (P = .014), and high-molecular-weight smoothelin by 40% (P = .015). Nerve density was decreased by 48% (P = .03 vs sham) paralleled by a 63% decrease of nerve-mediated contractility (P = .02). Following the implantation of composite mesh, the results of measurements were similar to sham (all P > .05), with a 39% increase in the myocyte diameter (P < .001) and a 2-fold increase in the level of alpha smooth muscle actin relative to Gynemesh (P = .045). Following the implantation of MatriStem alone, the number of small muscle bundles were increased 54% vs sham (P = .002), while the other parameters were not significantly different from sham (all P > .05).

CONCLUSION

The implantation of Gynemesh PS had a negative impact on the structural and functional integrity of vaginal smooth muscle evidenced by atrophic macro- and microscopic muscle morphology, decreased innervation, and impaired contractile property, consistent with a maladaptive remodeling response. The extracellular matrix bioscaffold (MatriStem), when used with Gynemesh PS as a composite (2 ply), attenuated the negative impact of Gynemesh PS; when used alone (6 ply), it induced adaptive remodeling as evidenced by an increased fraction of small smooth muscle bundles with normal contractility.

Interoception and Awareness of Physiological Sexual Arousal in Women With Sexual Arousal Concerns

Laboratory studies assessing physiological genital arousal have largely failed to find differences between women with and without female sexual arousal disorder (FSAD). Therefore, it is possible that women with FSAD may be unaware of their genital arousal response. The present study examined the extent to which women with FSAD can report their genital arousal response, as well as the role of interoception (body awareness) in this relationship. Additionally, this study examined the influence of interoception on the relationship between subjective and genital arousal. Twenty-six women who met criteria for FSAD (M age = 29.5, SD = 8.1 years) watched an erotic film and completed a series of questionnaires. Physiological (i.e., genital) and perceived genital arousal were measured continuously throughout the film. Results indicated women were able to perceive their level of physiological arousal. Greater levels of interoception were linked with stronger relationships between perceived and physiological arousal, but not between subjective and genital arousal. Methodological and clinical implications are discussed.

The Vaginal Pressure Inducer: A New Device to Test the (Un)pleasurableness and Tolerance of Vaginal Pressure and the Influence of Sexual Stimuli

To better understand the impact of sexual stimuli on genital pain, a new instrument was developed: the Vaginal Pressure Inducer (VPI). We administered gradually increasing vaginal pressure with the VPI to sexually functional women as they watched a neutral, erotic, or explicit sex film. Women had higher unpleasantness thresholds in a sexual context compared to a nonsexual context. Moreover, ratings of pleasurableness were higher in the sexual compared to neutral context and most so during the explicit sexual film. These results provide initial support for the suitability of the VPI to study determinants of pleasant and unpleasant appraisal of vaginal pressure.

Prostaglandin levels, vaginal innervation, and cyst innervation as peripheral contributors to endometriosis-associated vaginal hyperalgesia in rodents

Endometriosis is a painful condition characterized by growth of endometrial cysts outside the uterus. Here, we tested the hypothesis that peripheral innervation and prostaglandin levels contribute to endometriosis-associated pain. Female Sprague-Dawley rats (n = 16) were surgically instrumented by transplanting uterine tissue onto mesenteric arteries within the peritoneal cavity to create a model of endometriosis which forms extra-uterine endometrial cysts and vaginal hyperalgesia. Our results describe a significant positive correlation between endometriosis-induced vaginal hyperalgesia and cyst innervation density (sensory, r = 0.70, p = 0.003; sympathetic, r = 0.55, p = 0.03), vaginal canal sympathetic innervation density (r = 0.80, p = 0.003), and peritoneal fluid levels of the prostaglandins PGE2 (r = 0.65, p = 0.01) and PGF2α (r = 0.63, p = 0.02). These results support the involvement of cyst innervation and prostaglandins in endometriosis-associated pain. We also describe how sympathetic innervation density of the vaginal canal is an important predictor of vaginal hyperalgesia.

Anatomic distribution of nerves and microvascular density in the human anterior vaginal wall: prospective study

Background

The presence of the G-spot (an assumed erotic sensitive area in the anterior wall of the vagina) remains controversial. We explored the histomorphological basis of the G-spot.

Methods

Biopsies were drawn from a 12 o’clock direction in the distal- and proximal-third areas of the anterior vagina of 32 Chinese subjects. The total number of protein gene product 9.5–immunoreactive nerves and smooth muscle actin–immunoreactive blood vessels in each specimen was quantified using the avidin-biotin-peroxidase assay.

Results

Vaginal innervation was observed in the lamina propria and muscle layer of the anterior vaginal wall. The distal-third of the anterior vaginal wall had significantly richer small-nerve-fiber innervation in the lamina propria than the proximal-third (p = 0.000) and in the vaginal muscle layer (p = 0.006). There were abundant microvessels in the lamina propria and muscle layer, but no small vessels in the lamina propria and few in the muscle layer. Significant differences were noted in the number of microvessels when comparing the distal- with proximal-third parts in the lamina propria (p = 0.046) and muscle layer (p = 0.002).

Conclusions

Significantly increased density of nerves and microvessels in the distal-third of the anterior vaginal wall could be the histomorphological basis of the G-spot. Distal anterior vaginal repair could disrupt the normal anatomy, neurovascular supply and function of the G-spot, and cause sexual dysfunction.

TLR3 deficiency renders astrocytes permissive to herpes simplex virus infection and facilitates establishment of CNS infection in mice

Herpes simplex viruses (HSVs) are highly prevalent neurotropic viruses. While they can replicate lytically in cells of the epithelial lineage, causing lesions on mucocutaneous surfaces, HSVs also establish latent infections in neurons, which act as reservoirs of virus for subsequent reactivation events. Immunological control of HSV involves activation of innate immune pattern-recognition receptors such as TLR3, which detects double-stranded RNA and induces type I IFN expression. Humans with defects in the TLR3/IFN pathway have an elevated susceptibility to HSV infections of the CNS. However, it is not known what cell type mediates the role of TLR3 in the immunological control of HSV, and it is not known whether TLR3 sensing occurs prior to or after CNS entry. Here, we show that in mice TLR3 provides early control of HSV-2 infection immediately after entry into the CNS by mediating type I IFN responses in astrocytes. Tlr3-/- mice were hypersusceptible to HSV-2 infection in the CNS after vaginal inoculation. HSV-2 exhibited broader neurotropism in Tlr3-/- mice than it did in WT mice, with astrocytes being most abundantly infected. Tlr3-/- mice did not exhibit a global defect in innate immune responses to HSV, but astrocytes were defective in HSV-induced type I IFN production. Thus, TLR3 acts in astrocytes to sense HSV-2 infection immediately after entry into the CNS, possibly preventing HSV from spreading beyond the neurons mediating entry into the CNS.

[Combined lumbosacral and vaginal physiotherapy in the treatment of overactive bladder in postmenopausal women]

Efficacy of combined application of physical factors including lumbosacral magnetotherapy and vaginal vibromagnetic impact is shown in 48 postmenopausal women (mean age 62.5 +/- 1.6 years) with overactive bladder (OAB). Choice of this combination is explained by a multifactorial OAB pathogenesis and degenerative spinal diseases often encountered in postmenopausal women (70.8% in this study). The exposures of the spine and the bladder (vaginal) were made one after the other with duration of the first stage 10-15 min, of the second--5-7 min, the course consisted of 10-12 procedures. The results of the treatment were assessed by urination rhythm, volume, number of incontinence episodes. Quality of life was evaluated according to special questionnaires. Trophic function of the spinal cord and innervation of the bladder were studied by n. tibialis conduction measured by electroneuromyography (ENMG). The following results were obtained: reduction of urinations for 24 hours by 36.9%, urgent episodes--by 44%, urgent incontinence--by 59.7%. Voiding volume significantly increased (by 26%). A total score of anxiety related to OAB fell by 51.3%. M-response amplitude in ENMG rose 1.5-fold, while velocity of the impulse conduction along the n. tibialis enhanced 1.2-fold. The technique was accomplished with AMUS-01-Intramag device and attachment to it Rectomassager made in Russia.

[Expression of protein gene product 9.5, vasoactive intestinal peptide and neuropeptide Y in the mucosa of the neovagina after sigmoid colon vaginoplasty]

OBJECTIVE

To investigate re-innervation in the neovaginal mucosa of patients underwent sigmoid colon vaginoplasty in treatment of Mayer-Rokitansky-Kistner-Hauser Syndrome (MRKHS).

METHODS

Biopsies in the upper third of the posterior neovagina were taken in 20 patients treated by sigmoid colon vaginoplasty at 1, 2 and 3 years after surgery, respectively. Protein gene product 9.5 (PGP 9.5), vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) were detected by immunohistochemical method and compared with those in intact sigmoid colon mucosa.

RESULTS

(1) Density of nerve fiber: abundant distribution of PGP 9.5 nerve fibers were observed in the mucosal muscle layer, submucosa, and smooth muscle layer of the neovagina. The nerve fibers of VIP and NPY immunoreactivity were mainly distributed around blood vessels and in the smooth muscles. In the neovagina, the density of nerve fibers of PGP 9.5 of 17 ± 6 were much more than VIP of 2.9 ± 1.0 and NPY of 2.5 ± 0.8 significantly (P < 0.05). (2) Expression of PGP 9.5 in neovagina: at 1 year after surgery, PGP 9.5 positive expression of 14 ± 4 was significantly lower in the neovagina than 28 ± 7 in the intact sigmoid colon (P < 0.05). However, after 2 to 3 years, its expression displayed an upgrade tendency in the neovagina and was significantly higher at the 3 year postoperatively than that at the 1 years postoperatively (22 ± 7 vs. 14 ± 4, P < 0.05). The changes were much more obvious in submucosa. (3) The expression of VIP and NPY in neovagina: at 1 year after surgery, VIP and NPY positive nerve fibers were also decreased in the neovagina when compared with those in the intact sigmoid colon (2.3 ± 0.7 vs. 5.3 ± 1.4, P < 0.05; 2.5 ± 1.1 vs. 5.5 ± 1.1, P < 0.05). At 2 to 3 years after surgery, the positive VIP fiber showed initially decreased and subsequently increased tendency. The density of VIP of 3.7 ± 0.7 in the neovagina at 3 years postoperatively was higher than 2.3 ± 0.7 at 1 years postoperatively (P < 0.05). No significant up-regulation was observed in NPY-positive expression in the neovagina within 3 years after operation.

CONCLUSIONS

Distribution of sensory PGP 9.5, VIP and NPY immunoreactive nerve fibers was similar to the pattern observed within the intact sigmoid colon wall. The number of nerve fibers in the neovagina decreased after surgery and then increased subsequently within 3 years after surgery.

Addressing anxiety in vivo in physiotherapy treatment of women with severe vaginismus: a clinical approach

Physiotherapy for the treatment of vaginismus is perceived as an intervention aimed to normalize muscle tone of the pelvic floor in order to allow vaginal penetration in accordance with the traditional view of vaginal spasm as its defining feature. Newer definitions recognize the experience of anxiety as well as pain, and effective treatment approaches should address these components as well. Physiotherapists often encounter women who, as a result of severe anxiety, are unable to undergo examination and treatment, despite their expressed desire to do so. This article describes a therapeutic intervention designed to help women with vaginismus prepare for examination and treatment by addressing the component of anxiety in real-life situations. This approach is also appropriate for nurse practitioners and physicians who work with this patient population and may be adapted for sex therapists to teach as a home exercise.

[Relationship between pain and nerve fibers distribution in multiple endometriosis lesions]

OBJECTIVE

To investigate the relationship between the distribution of nerve fibers in multiple endometriosis lesions and pelvic pain.

METHODS

From Sept. 2007 to Sept. 2008, 120 endometriosis patients treated in Peking Union Hospital were enrolled in this study, which including 19 cases with stage I, 29 cases with stage II, 44 cases with stage III and 28 cases with stage IV. The pain symptom was evaluated by visual analogue scales (VAS) score and nerve fibers in multiple endometriosis lesions were detected by immunohistochemical staining.

RESULTS

The number of nerve fibers in multiple endometriosis lesions were (29.74+/-17.33)/mm2 in uterosacral ligament, (24.53+/-13.34)/mm2 in vaginal septum, (17.09+/-10.09)/mm2 in uterus rectum crux, (6.77+/-4.21)/mm2 in peritoneal endometriosis lesions, (0.07+/-0.25)/mm2 in endometriosis ovarian cyst wall. The number of nerve fibers in uterosacral ligament was mostly correlated with the degree of pain (r=0.56). The nerve fibers of uterus rectum crux and vaginal septum were correlated with defecation pain (r=0.58 and 0.41) and dyspareunia (r=0.82 and 0.67), which were significantly higher than those in endometriosis leision in peritoneum and ovary. There was no significant different number of nerve fibers among different stage disease (P>0.05).

CONCLUSION

There was significantly different distribution of nerve fibers in multiple endometriosis lesions, which was correlated with dysmenorrhea, anus pain, dyspareunia and chronic pelvic pain, not with clinical staging.

Re-innervation pattern of the 'neovagina' created from the bladder flap in patients with Mayer-Rokitanski-Kistner-Hauser syndrome: an immunochemical study

BACKGROUND

Cystovaginoplasty (CVP) is a method of vaginal reconstruction in women with Mayer-Rokitansky-Kistner-Hauser Syndrome (MRKHS). The neo-vagina allows normal sexual intercourses, but after CVP, the sexual life of patients with MRKHS does not differ significantly from normal females. Therefore, we decided to elucidate the pattern of sensory re-innervation of the bladder flap used for the surgery.

METHODS

Biopsies were taken from vaginal vestibule and urinary bladder during the CVP and 1 year later in four patients with MRKHS. The following neurotransmitters were studied calcitonin gene-related peptide (CGRP), galanin (GAL), vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP).

RESULTS

CGRP and PACAP nerve fibres were sparse under the urothelium and in submucosal layer of the neovagina, they were more numerous around blood vessels and in the vicinity of smooth muscles. This was similar to the pattern observed in the urinary bladder. VIP- and GAL-positive nerve fibres were most numerous in the submucosa around blood vessels and in smooth muscle bundles of neovagina. They were distinctly less numerous beneath the epithelium. This innervation pattern mimicked that seen in normal vagina and in vaginal vestibule of patients with MRKHS.

CONCLUSIONS

Our findings demonstrate considerable nervous system plasticity in the bladder flap. Distribution of presumably sensory CGRP and PACAP immunoreactive nerve fibers was similar to the pattern observed within the intact bladder wall, and VIP or GAL immunoreactive nerve fibers (vasomotor functions) were distributed in a manner similar to that observed in the intact vaginal wall.

[Effect of pregnancy and spontaneous delivery on the morphology of levator ani muscle and expression of vaginal nerve fibers]

OBJECTIVE

To investigate the effect of pregnancy and spontaneous delivery on the morphologic characteristics of the levator ani muscle and innervation of the vaginal mucosa.

METHODS

Eight nullipara without pelvic floor dysfunction (PFD) and 64 normal primipara undergoing spontaneous delivery were enrolled in this study during July to December 2006 in Peking Union Medical College Hospital. Biopsy specimens of levator ani muscle (LAM) and anterior and posterior vaginal walls were obtained from the puerpera as well as from the 8 nullipara undergoing vaginal operation. The structures of LAM were examined with histological techniques. Vaginal mucosa specimens were examined using immunohistochemistry staining for protein gene product 9.5 (PGP 9.5), vasoactive intestinal peptide (VIP) and ne uropeptide Y (NPY), and the positive stained nerve fibers were calculated respectively.

RESULTS

The LAMs of the puerpera undergoing spontaneous delivery presented myogenetic and neurogenetic changes, both acute and chronic. Type I muscular fibers were predominant (79%) with both types increasing in diameters [(86 +/- 9) microm and (79 +/- 15) microm]. Significantly different (P < 0.05) innervation of PGP 9.5, VIP, and NPY nerve fibers was observed between epithelial lamina of anterior vaginal wall (5.9 +/- 3.3, 7.6 +/- 3.1 and 8.2 +/- 3.2, respectively) and that of posterior vaginal wall (3.8 +/- 2.9, 5.9 +/- 3.1 and 6.0 +/- 3.0, respectively), with the nerve fibers being more in epithelial lamina of anterior vaginal wall, while no difference in the innervation of nerve fibers was observed in the lamina propria. Significantly different (P < 0.05) innervation of PGP 9.5 and VIP nerve fibers was observed in the lamina propria of the anterior vaginal wall in puerperal undergoing vaginal delivery (6.9 +/- 3.2 and 4.9 +/- 2.1) compared with those in nullipara (3.9 +/- 3.6 and 3.1 +/- 1.2).

CONCLUSIONS

Pathologic changes occur in LAMs and pelvic floor nerves during labor and delivery. LAM fibers become hypertrophy to adapt to the physiological changes during pregnancy. Richer innervation of PGP 9.5 and VIP nerve fibers in the lamina propria of the anterior vaginal wall in puerpera undergoing spontaneous delivery is beneficial for dilation of the blood vessels and smooth muscles and makes preparation for delivery.

Vaginal blood flow after radical hysterectomy with and without nerve sparing. A preliminary report

Radical hysterectomy with pelvic lymphadenectomy (RHL) for cervical cancer causes damage to the autonomic nerves, which are responsible for increased vaginal blood flow during sexual arousal. The aim of the study of which we now report preliminary data was to determine whether a nerve-sparing technique leads to an objectively less disturbed vaginal blood flow response during sexual stimulation. Photoplethysmographic assessment of vaginal pulse amplitude (VPA) during sexual stimulation by erotic films was performed. Subjective sexual arousal was assessed after each stimulus. Thirteen women after conventional RHL, 10 women after nerve-sparing RHL, and 14 healthy premenopausal women participated. Data were collected between January and August 2006. The main outcome measure was the logarithmically transformed mean VPA. To detect statistically significant differences in mean VPA levels between the three groups, a univariate analysis of variance was used. Mean VPA differed between the three groups (P= 0.014). The conventional group had a lower vaginal blood flow response than the control group (P= 0.016), which tended also to be lower than that of the nerve-sparing group (P= 0.097). These differences were critically dependent on baseline vaginal blood flow differences between the groups. The conventional group follows a vaginal blood flow pattern similar to postmenopausal women. Conventional RHL is associated with an overall disturbed vaginal blood flow response compared with healthy controls. Because it is not observed to the same extent after nerve-sparing RHL, it seems that the nerve-sparing technique leads to a better overall vaginal blood flow caused by less denervation of the vagina.

Success of sildenafil treatment in neurogenic female sexual dysfunction caused by L5-S1 intervertebral disk rupture: a case report

Female sexual dysfunction can be founded by disorders of sexual desire, arousal, orgasm, and sexual pain. Physiologic sexual dysfunction can, in many cases, be the result of impaired neurovascular tone to the clitoris and vagina. The vagina and clitoris both contain erectile tissue and phosphodiesterase type 5 (PDE5). Accordingly, the use of sildenafil, a PDE5 inhibitor, has been studied in relation to neurogenic female sexual dysfunction. The present case report addresses neurogenic female sexual dysfunction from the result of a ruptured L5-S1 intervertebral disk. The patient was treated with sildenafil, and her symptoms were recorded using a Female Sexual Function Index score. Discussion of the use of sildenafil in women, with an emphasis on female neurovascular sexual physiology and function, is reviewed.

Influence of endometriosis on visceromotor and cardiovascular responses induced by vaginal distention in the rat

This study examined pseudoaffective responses elicited by vaginal distention in urethane-anesthetized rats, and tested hypotheses that responses would be increased by endometriosis (ENDO) and vary with the estrous cycle. Three groups were studied: ENDO, shamENDO, and Naive. ENDO was induced by autotransplanting small pieces of uterine horn (or, for shamENDO, fat) on mesenteric arteries. Ten weeks later, rats in proestrus or metestrus were anesthetized with urethane. Distendable latex balloons were inserted into the vaginal canal. While an increasing series of vaginal distentions was delivered, changes in electromyographic activity of the external oblique musculature (visceromotor response, VMR) and mean arterial pressure (pressor) responses were simultaneously measured. Vaginal distention produced VMR and pressor responses in all groups. These responses were significantly greater in ENDO than in the other groups, and greater in proestrus than metestrus. Although the overall amount of cystic tissue was greater in proestrous than metestrous rats, there was no correlation between these amounts and VMR or pressor responses. Acute spinalization (T8-T9) and bilateral pelvic, but not hypogastric, neurectomy attenuated both VMR and pressor responses, supporting the hypothesis that vaginal nociception involves suprathoracic spinal processing of information conveyed by the pelvic nerve. These effects on VMR and pressor responses to vaginal distention parallel behavioral escape responses to the same stimuli reported previously. The findings encourage continued use of VMR and pressor responses for further investigation of mechanisms underlying pain associated with ENDO and its potential treatment.

ORIGINAL RESEARCH—WOMEN’S SEXUAL HEALTH: Physiological Changes in Female Genital Sensation During Sexual Stimulation

INTRODUCTION

A normal sexual response in the female depends on the integrity of afferent sensory input from the genital region. So far genital sensation has been investigated only during a non-excitatory state, and the sensory physiological changes, which occur during the sexual cycle in this region, are still obscured.

AIM

To investigate the sensory status of the female genital region during sexual arousal and orgasm.

MAIN OUTCOME MEASURES

Genital sensory thresholds measured by Quantitative Sensory Testing (vibratory and thermal) were compared in a non-excitatory vs. excitatory state in normal sexually functioning females.

METHODS

Eleven healthy female volunteers were recruited and attended three separate visits. During each session only one anatomical site, either clitoris or vagina was tested for either vibratory or thermal stimuli. A psychophysical method of limits was employed for threshold determination of warm or vibratory stimuli. In each session, all women were tested at baseline, immediately after arousal, after orgasm and three more measurements - 5, 10, and 20 minutes during the recovery state.

RESULTS

A significant decrease in clitoral vibratory sensation threshold was observed between the baseline and the arousal phases (P = 0.003). Comparison of vibratory sensation between baseline and following orgasm at the clitoral and vaginal region showed a significant difference (P < 0.001) for both regions. These changes were not significant for thermal threshold sensation at the clitoral region (P = 0.6).

CONCLUSIONS

This is the first time that genital sensation has been measured during the excitatory phase of the female sexual cycle. This normative data may serve as a baseline for further investigations of the sensory input of the genital organs during intercourse in pathological states.

Itch and burning pain in women with partial vaginismus with or without vulvar vestibulitis

Fifty-three women with partial vaginismus with or without vulvar vestibulitis and 27 asymptomatic women estimated sensations of burning pain and itch at 20 standardized moments during a standardized penetration situation, including vaginal muscle contractions. Forty-three women with partial vaginismus (81.1%) reported burning pain, 23 (43.4%) itch, and 22 (41.5%) both complaints, compared to 0% of the asymptomatic women. In 17 of 22 cases, burning pain preceded the appearance of itch and in four cases the two complaints coincided. The median time from the moment when burning pain started until itch appeared was 150 seconds.

Facilitation of estrous behavior by vaginal cervical stimulation in female rats involves alpha1-adrenergic receptor activation of the nitric oxide pathway

In estrogen-primed female rats, vaginal cervical stimulation (VCS) provided by male intromissions or by an experimenter enhances estrous behaviors exhibited by females during subsequent mating with a male. We tested the hypothesis that alpha(1)-adrenergic receptors, acting via the nitric oxide-cGMP-protein kinase G pathway, mediate VCS-induced facilitation of female reproductive behaviors. Ovariectomized, estradiol-primed rats received intracerebroventricular (icv) infusions of vehicle or pharmacological antagonists 15 or 60min before VCS. Estrous behaviors (lordosis and proceptivity) in the presence of a male were recorded immediately (0min), and 120min following VCS. First we verified that VCS, but not manual flank stimulation alone, enhanced estrous behaviors when females received icv infusion of the vehicles used to administer drugs. Increased estrous behavior was apparent immediately following VCS and persisted for 120min. We then infused prazosin, phenoxybenzamine (alpha(1)-adrenergic receptor antagonists), yohimbine, idaxozan (alpha(2)-adrenergic receptor antagonists), or propranolol (beta-adrenergic receptor antagonist) 15min prior to the application of VCS in females primed with 5mug estradiol benzoate. Only alpha(1)-adrenergic antagonists inhibited VCS facilitation of estrous behavior, apparent 120min after VCS. Finally, we administered specific inhibitors of soluble guanylyl cyclase, nitric oxide synthase or protein kinase G icv 15 or 60min before VCS. All three agents significantly attenuated VCS facilitation of estrous behavior. These data support the hypothesis that endogenously released norepinephrine, acting via alpha(1)-adrenergic receptors, mediates the facilitation of lordosis by VCS, and are consistent with a mechanism involving alpha(1)-adrenergic activation of the nitric oxide/cGMP/protein kinase G pathway.

ORIGINAL RESEARCH—BASIC SCIENCE: A Prospective Study Examining the Anatomic Distribution of Nerve Density in the Human Vagina

INTRODUCTION

Women possess sufficient vaginal innervation such that tactile stimulation of the vagina can lead to orgasm. However, there are few anatomic studies that have characterized the distribution of nerves throughout the human vagina.

AIM

The aim of this prospective study was to better characterize the anatomic distribution of nerves in the adult human vagina. A secondary aim was to assess whether vaginal innervation correlates with the subject's demographic information and sexual function.

METHODS

Full-thickness biopsies of anterior and posterior vagina (proximal and distal), cuff, and cervix were taken during surgery in a standardized manner. Specimens were prepared with hematoxylin and eosin, and S100 protein immunoperoxidase. The total number of nerves in each specimen was quantified. Enrolled patients completed a validated sexual function questionnaire (Female Sexual Function Index, FSFI) preoperatively.

MAIN OUTCOME MEASURES

A description of vaginal innervation by location and an assessment of vaginal innervation in association with the subject's demographic information and sexual function.

RESULTS

Twenty-one patients completed this study, yielding 110 biopsy specimens. Vaginal innervation was somewhat regular, with no site consistently demonstrating the highest nerve density. Nerves were located throughout the vagina, including apex and cervix. No significant differences were noted in vaginal innervation based on various demographic factors, including age, vaginal maturation index, stage of prolapse, number of vaginal deliveries, or previous hysterectomy. There were no correlations between vaginal nerve quantity and FSFI domain and overall scores. Fifty-seven percent of the subjects had female sexual dysfunction; when compared to those without dysfunction, there were no significant differences in total or site-specific nerves.

CONCLUSIONS

In a prospective study, vaginal nerves were located regularly throughout the anterior and posterior vagina, proximally and distally, including apex and cervix. There was no vaginal location with increased nerve density. Vaginal innervation was not associated with demographic information or sexual function.

A clinicoanatomical study of the novel nerve fibers linked to stress urinary incontinence: the first morphological description of a nerve descending properly along the anterior vaginal wall

When performing anterior colporrhaphy for cystocele, most pelvic surgeons have not considered the neuroanatomy that contributes to urethral function. The aim of the study was to anatomically identify nerve fibers located in the anterior vagina associated with the pathogenesis of incontinence and pelvic organ prolapse. Anterior vaginal specimens were obtained from 17 female cadavers and 33 cases of clinical cystocele by anterior vaginal resection. The specimens were step-sectioned and stained with hematoxylin-eosin, S100 antibody, and tyrosine hydroxylase antibody. As a result, descending nerves 50-200 microm in thickness were identified between the urethra and vagina. They were located more than 10 mm medially from a cluster of nerves found almost along the lateral edge of the vagina and stained with S100 and tyrosine hydroxylase antibody, originated from the cranial part of the pelvic plexus, and appeared to terminate at the urethral smooth muscles. The authors classified the density of S100 positive nerve fibers in the anterior vaginal wall obtained from clinically operated cases of cystocele into three grades (Grade 1, nothing or a few thin nerves less than 20 microm in diameter; Grade 2, thick nerves more than 50 microm in diameter and thin nerves; Grade 3, more than 3 thick nerves in one field at an objective magnification of 40x). Mean urethral mobility (Q-tip) values (28.1 degrees +/-+/- 19.6 degrees ) observed in the Grade 3 cases was significantly lower than those (50.0 degrees +/-+/- 27.4 degrees and 59.4 degrees +/-+/- 19.9 degrees ) in Grade 2 and Grade 1, respectively. In addition, the presence of preoperative or postoperative stress urinary incontinence in the cases of Grade 1 was significantly higher than those of the cases with S100 positive stained nerves. In conclusion, the novel nerve fibers immunohistochemically identified in the anterior vaginal wall are different from those of the common nervous system or the pelvic floor and are associated with the pathogenesis of urethral hypermobility.

Immunoreactivities to protein gene product 9.5, neurofilament protein and neuron specific enolase in nerves in the oviduct of the sexually immature ostrich, Struthio camelus

The present study investigated the distribution of nerves in the oviduct of the sexually immature ostrich. The presence of protein gene product 9.5, neurofilament protein and neuron specific enolase nerve fibres were demonstrated in the infundibulum, magnum, isthmus, shell gland and vagina. Nerve fibres containing protein gene product 9.5, neuron specific enolase and neurofilament protein were particularly numerous in the tunica muscularis and intermuscular connective tissue areas of the shell gland and vagina. The presence of a large number of nerves in these oviductal regions is probably important in the coordination of muscle contraction. An interesting finding of the study was the presence of protein gene product 9.5 and neuron specific enolase immunopositive nerve fibres in the walls of blood vessels. It is likely that these nerves are autonomicin nature and play a role in the regulation of blood flow. This study has shown the presence of an extensive neural network in the oviduct of the ostrich. In addition, the results of the investigation have shown that the neuronal markers protein gene product 9.5, neurofilament protein and neuron specific enolase can be used to demonstate nerve fibres in the ostrich.

The effect of ovariectomy on rat vaginal tissue contractility and histomorphology

INTRODUCTION

Ovarian hormones have an important role in age-related genital arousal disorders; however, our knowledge regarding possible vaginal wall morphology and contractility changes in low-hormonal states is limited.

AIMS

To investigate morphological and functional alterations in the vaginal tissue in a rat ovariectomy model and to show the differences between proximal and distal vagina.

METHODS

Six weeks following ovariectomy, vaginal tissues were examined under light and electron microscopy. Circularly cut distal and proximal tissues were studied in the organ bath under isometric tension and compared with age-matched controls. Contractile responses to electrical field stimulation (EFS), phenylephrine, carbachol, and the effects of alpha-1 and alpha-2 blockade on EFS-induced contractility were investigated. Relaxation responses to EFS and vardenafil were investigated in precontracted strips.

MAIN OUTCOME MEASURES

Differences between control and ovariectomy groups in terms of vaginal tissue contractility and histomorphological properties.

RESULTS

Distal vagina showed different epithelial characteristics and a better-developed muscularis compared with proximal vagina. Ovariectomy caused thinning of the epithelium, severe degeneration in epithelial architecture, and smooth muscle atrophy. Contraction and relaxation responses of distal strips were significantly lower in ovariectomized rats. Contractile responses to neuropharmacological stimulation were insignificant in proximal strips of both groups. EFS-induced contractions in distal strips diminished significantly after alpha-1 and alpha-2 adrenergic blockade. EFS caused frequency-dependent relaxation responses in precontracted distal strips, which were significantly decreased after nitric oxide synthase inhibition.

CONCLUSIONS

Ovariectomy causes significant alteration in rat vaginal tissue morphology and contractility. Contraction and relaxation responses of distal vagina are significantly greater compared with morphologically distinct proximal vagina. Alpha-1 and alpha-2 receptors are the main mediators of contraction in distal rat vaginal tissue whereas nitric oxide pathway may have at least a partial role in relaxation. Main mediators of the rat vaginal tissue relaxation and the effect of ovariectomy on this regulation are yet to be defined.

Identification of neural circuits involved in female genital responses in the rat: a dual virus and anterograde tracing study

The spinal and peripheral innervation of the clitoris and vagina are fairly well understood. However, little is known regarding supraspinal control of these pelvic structures. The multisynaptic tracer pseudorabies virus (PRV) was used to map the brain neurons that innervate the clitoris and vagina. To delineate forebrain input on PRV-labeled cells, the anterograde tracer biotinylated dextran amine was injected in the medial preoptic area (MPO), ventromedial nucleus of the hypothalamus (VMN), or the midbrain periaqueductal gray (PAG) 10 days before viral injections. These brain regions have been intimately linked to various aspects of female reproductive behavior. After viral injections (4 days) in the vagina and clitoris, PRV-labeled cells were observed in the paraventricular nucleus (PVN), Barrington's nucleus, the A5 region, and the nucleus paragigantocellularis (nPGi). At 5 days postviral administration, additional PRV-labeled cells were observed within the preoptic region, VMN, PAG, and lateral hypothalamus. Anterograde labeling from the MPO terminated among PRV-positive cells primarily within the dorsal PVN of the hypothalamus, ventrolateral VMN (VMNvl), caudal PAG, and nPGi. Anterograde labeling from the VMN terminated among PRV-positive cells in the MPO and lateral/ventrolateral PAG. Anterograde labeling from the PAG terminated among PRV-positive cells in the PVN, ventral hypothalamus, and nPGi. Transynaptically labeled cells in the lateral hypothalamus, Barrington's nucleus, and ventromedial medulla received innervation from all three sources. These studies, together, identify several central nervous system (CNS) sites participating in the neural control of female sexual responses. They also provide the first data demonstrating a link between the MPO, VMNvl, and PAG and CNS regions innervating the clitoris and vagina, providing support that these areas play a major role in female genital responses.

Innervation of the rectovaginal wall in patients with rectocele compared to healthy controls

AIMS

To evaluate if pelvic floor innervation differed in patients with rectocele compared to control subjects and to assess if nerve fiber density of the rectovaginal wall correlated to the clinical presentation of rectocele.

METHODS

Biopsies from 24 female patients with posterior vaginal wall prolapse stage II (ICS-classification) and rectocele verified at defecography were compared to specimens from age and parity-matched control subjects without posterior vaginal wall prolapse. Nerve fiber density was measured using protein gene product (PGP-9.5) antibodies at immunohistochemistry. Anorectal symptoms were recorded using bowel and anorectal function questionnaires.

RESULTS

The two groups were comparable in age and parity. Mean nerve fiber immunofluorescence intensity was 150.3 +/- 12.5 SD in the patient group compared to 139.3 +/- 8.5 SD in the control group (P < 0.01). Symptoms of anorectal dysfunction were more common in the patient group compared to control subjects (P < 0.01) but there was no difference in anal continence. At logistic regression analysis, nerve fiber immunofluorescence intensity showed no significant correlation to age, menopausal age, parity, body mass index (BMI), prolapse quantification, or any specific self-reported anorectal symptom. Increased nerve fiber immunofluorescence intensity was correlated to increased perineal descent (OR 1.3, 95% CI 1.1-2.1) although not to the size of the rectocele (OR 0.5, 95% CI 0.9-1.2).

CONCLUSIONS

Our results show that rectocele may be associated with increased rectovaginal innervation, suggestive of reinnervation of the rectovaginal wall. Nerve fiber density correlated poorly with findings at clinical and radiological examination. Neurochemical characterization of the rectovaginal wall may provide further understanding of the pathogenesis of rectocele.

Differential effects of estradiol, progesterone, and testosterone on vaginal structural integrity

Ovarian steroids are known to be important in maintaining vaginal tissue, and evidence is mounting that imbalances in the hormonal milieu contribute to vaginal pathophysiology. To date, limited data are available on the effects of hormone deprivation and replacement on vaginal tissue morphology and vaginal innervation. The goal of this study was to assess the dynamic changes in vaginal tissue structure in response to sex steroid hormone deprivation and administration. Female Sprague-Dawley rats were either kept intact (controls) or ovariectomized. Ovariectomized animals were treated with vehicle, estradiol, testosterone, progesterone, or a combination of estradiol plus testosterone or progesterone. Histological techniques, including stereological analysis and immunohistochemistry for localization of neuronal markers, were used. Ovariectomy produced a significant decrease in epithelial height that was restored with estradiol replacement. Interestingly, a subphysiological dose of estradiol resulted in hyperplasia of the vaginal epithelium and nonvascular smooth muscle. Neither testosterone nor progesterone had a significant effect on epithelial height or muscularis thickness. However, testosterone treatment resulted in a significant increase in small adrenergic nerve fibers. Addition of either testosterone or progesterone to estradiol mitigated but did not abolish the effects of estradiol alone. This study demonstrates that estradiol and testosterone have differential effects on vaginal tissue parameters and that ovarian hormones are critical for the maintenance of genital tissue structure. Present observations also suggest that combined replacement regimens may be required for an optimal physiological response.

Functional imaging of stress urinary incontinence

Stress urinary incontinence (SUI) is defined as an involuntary loss of urine during increases in intraabdominal pressure such as coughing or laughing. It is often a consequence of weakness of the pelvic floor. Treatment of SUI consists of pelvic floor muscle training with EMG-biofeedback (PFMT) or contraction-exercises, with voluntary pelvic contractions in order to strengthen the pelvic floor. We investigated neuroplastic changes comparing PFMT with EMG-biofeedback before and after training in ten female patients with SUI using event-related functional Magnetic Resonance Imaging (fMRI). After a 12-week training a more focused activation in the primary motor and somatosensory cortical representation sites of the lower urogenital tract was found. In addition, reductions in brain activation in the insula, right frontal operculum and the anterior cingulate cortex suggest changes in emotional arousal in micturition after treatment. These changes are related to clinical improvement documented by decreased number of incontinence episodes and increased EMG-activity of the pelvic floor muscles after training. The changes in EMG-activity were correlated with heightened BOLD responses in the primary motor and primary sensory cortical representation sites of the lower urogenital tract.

Cyclic adenosine monophosphate and cyclic guanosine monophosphate-phosphodiesterase isoenzymes in human vagina: relation to nitric oxide synthase isoforms and vasoactive intestinal polypeptide-containing nerves

OBJECTIVES

To evaluate the distribution of cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) phosphodiesterases (PDEs) in relation to nitric oxide synthase isoforms and vasoactive intestinal polypeptide (VIP) in specimens of the human vagina. Nitric oxide and VIP, mediating biologic signals through cGMP and cAMP, have been assumed to be involved in the control of vaginal smooth muscle.

METHODS

Immunohistochemical techniques were applied to sectioned specimens of the human vaginal wall to evaluate the presence of the PDE isoenzymes 3, 4, 5, and 10 in relation to neuronal nitric oxide synthase (nNOS), endothelial NOS (eNOS), and VIP.

RESULTS

Immunoreactivity (IR) for cAMP-degrading PDE-4 was observed in the vaginal nonvascular smooth musculature, as well as in the wall of subepithelial arteries. VIP-IR nerves innervated the smooth muscle portion of the vaginal wall and also formed a subepithelial network. Immunoreactivity specific for PDE-5 was also registered in vascular and nonvascular vaginal smooth muscle. Immunosignals for eNOS were detected in the endothelial lining of arteries containing PDE-5-IR smooth muscle cells. These arteries were supplied by nNOS-IR nerve fibers. PDE-10-IR smooth muscle cells were located in muscle bundles of the vaginal wall.

CONCLUSIONS

Our study revealed immunoreactivity specific for PDE-4, PDE-5, and PDE-10 in the vascular and nonvascular smooth muscle of the vagina. Immunosignals for PDE-4 and PDE-5 were also observed in close proximity to nNOS-IR or VIP-IR nerve fibers or to eNOS-IR endothelial cells. The distribution of PDEs may indicate a role of these enzymes in the control of the function of the human vagina.

Clitoral anatomy in nulliparous, healthy, premenopausal volunteers using unenhanced magnetic resonance imaging

PURPOSE

We determined the magnetic resonance imaging (MRI) characteristics of normal clitoral anatomy.

MATERIALS AND METHODS

A series of MRI studies of 10 healthy, nulliparous volunteers with no prior surgery and normal pelvic examination was studied and the key characteristics of clitoral anatomy were determined. A range of different magnetic resonance sequences was used without any contrast agent.

RESULTS

The axial plane best revealed the clitoral body and its proximal continuation as the paired crura. The glans was seen more caudal than the body of the clitoris. The bulbs of the clitoris had the same signal as the rest of the clitoris in the axial plane and they related consistently to the other erectile structures. The bulbs, body and crura formed an erectile tissue cluster, namely the clitoris. In turn, the clitoris partially surrounded the urethra and vagina, forming a consistently observed tissue complex. Midline sagittal section revealed the shape of the body, although in this plane the rest of the clitoris was poorly displayed. The coronal plane revealed the relationship between the clitoral body and labia. The axial section cephalad to the clitoral body best revealed the vascular component of the neurovascular bundle to the clitoris. The fat saturation sequence particularly highlighted clitoral anatomy in healthy, premenopausal, nulliparous women.

CONCLUSIONS

Normal clitoral anatomy has been clearly demonstrated using noncontrast pelvic MRI.

Women's Sexual Pain and Its Management

INTRODUCTION

Approximately 15% of women have chronic dyspareunia that is poorly understood, infrequently cured, often highly problematic, and distressing. Chronic dyspareunia is an urgent health issue.

AIM

To provide recommendations/guidelines concerning state-of-the-art knowledge for the assessment and management of women's sexual pain disorders.

METHODS

An international consultation, in collaboration with the major sexual medicine associations, assembled over 200 multidisciplinary experts from 60 countries into 17 committees. One six-member committee focused on women's sexual pain disorders, developing recommendations over a 2-year period.

MAIN OUTCOME MEASURE

Expert opinion was based on grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.

RESULTS

There is increasing evidence for the role of neuropathic pain mechanisms in the pathophysiology of sexual pain disorders. Empirical literature has demonstrated the comorbid presence of clinical psychopathology. With regard to the pathophysiologic role of the pelvic floor and sexual pain disorders, studies reveal that (i) differentiation between vaginismus and dyspareunia using clinical tools is difficult; (ii) vaginal spasms have not been identified; (iii) physical therapists can differentiate vaginismic women from matched controls based on muscle tone/strength differences; (iv) the traditional treatment of vaginismus with vaginal "dilatation" plus psycho-education, desensitization, and so forth is not evidence-based; (v) pelvic floor muscle tone/strength measures for women suffering from vulvar vestibulitis syndrome are intermediate between those of women with vaginismus and no-pain controls; and (vi) the pelvic floor musculature is indirectly innervated by the limbic system and highly reactive to emotional stimuli and states. Pelvic floor therapies for dyspareunia may be effective.

CONCLUSION

Recommendations include (i) revising the definitions of vaginismus and dyspareunia; (ii) integration of treatment approaches; (iii) validation of nonspecific treatment effects; (iv) controlled studies to test interventions; and (v) sexuality education to help prevent sexual pain.

Effect of vaginal distension on anorectal function: identification of the vagino-anorectal reflex

BACKGROUND

Sexual stimulation produces not only reflex changes in the female external and internal reproductive organs but also extragenital reactions. A mention of the response of the anal sphincters and the rectum to penile thrusting could not be traced in the literature. We investigated the hypothesis that the anal sphincters and the rectum respond to penile thrusting in a way that prevents gas and fecal leakage during sexual intercourse.

METHODS

The response of the external anal sphincter (EAS) and the internal anal sphincter (IAS) and the rectum to vaginal balloon (condom) distension was recorded in 23 healthy women (age: 33.7 +/- 7.3 years). The vaginal condom was inflated with air in increments of 50-300 ml, and the electromyographic (EMG) activity of the EAS and the IAS, as well as rectal pressure, was recorded. The test was repeated after separate anesthetization of the vagina, the rectum, the EAS and the IAS and after the use of normal saline instead of lidocaine.

RESULTS

Vaginal distension reduced the rectal pressure in the ratio of expansion of the vaginal volume up to a certain volume, beyond which the rectal pressure ceased to decline when more distending volume was added. Similarly, the internal sphincter EMG activity increased progressively on incremental vaginal distension increase until the 150-ml distension was reached after which more vaginal distension caused no further increase of the EMG activity; external sphincter EMG activity showed no response. Vaginal distension, while the vagina, the rectum, the EAS, and the IAS had been separately anesthetized, produced no significant change, but saline did.

CONCLUSIONS

Vaginal balloon distension appears to effect rectal wall relaxation and increase of the internal sphincter tone. This seems to provide a mechanism to avoid rectal contents leakage during coitus. Rectal and internal sphincter response to vaginal distension is suggested to be mediated through a reflex we term 'vagino-anorectal reflex', which seems to be evoked by vaginal distension during penile thrusting. The reflex may prove of diagnostic significance in sexual disorders; further studies are needed in order to investigate this point.

Functional MRI of the brain during orgasm in women

Women diagnosed with complete spinal cord injury (SCI) at T10 or higher report sensations generated by vaginal-cervical mechanical self-stimulation (CSS). In this paper we review brain responses to sexual arousal and orgasm in such women, and further hypothesize that the afferent pathway for this unexpected perception is provided by the Vagus nerves, which bypass the spinal cord. Using functional magnetic resonance imaging (fMRI), we ascertained that the region of the medulla oblongata to which the Vagus nerves project (the Nucleus of the Solitary Tract or NTS) is activated by CSS. We also used an objective measure, CSS-induced analgesia response to experimentally induced finger pain, to ascertain the functionality of this pathway. During CSS, several women experienced orgasms. Brain regions activated during orgasm included the hypothalamic paraventricular nucleus, amygdala, accumbens-bed nucleus of the stria terminalis-preoptic area, hippocampus, basal ganglia (especially putamen), cerebellum, and anterior cingulate, insular, parietal and frontal cortices, and lower brainstem (central gray, mesencephalic reticular formation, and NTS). We conclude that the Vagus nerves provide a spinal cord-bypass pathway for vaginal-cervical sensibility and that activation of this pathway can produce analgesia and orgasm.

Is the histomorphological concept of the female pelvic floor and its changes due to age and vaginal delivery correct?

AIMS

To compare the histomorphology of pelvic floor specimens of 94 female cadavers, ten male cadavers, and 24 female symptomatic patients who underwent pelvic floor surgery, and to evaluate the association of age, parity, and sex to myogenic and/or neurogenic changes to the levator ani muscle (LAM).

METHODS

The pelvic floor was biopsied at the pubococcygeus, the iliococcygeus and the coccygeus muscle. After staining, signs for myogenic/neurogenic changes to the muscle were evaluated (fibrosis, variation in fiber diameter, centralization of nuclei, small angulated fibers, and type grouping). To identify the intact neuromuscular junction stainings with NCAM (neuronal cell adhesion molecule) and acetylcholinesterase (ACE) were used.

RESULTS

A significant influence of age and parity on the histomorphological criteria of myogenic cell-damage was shown in this study. Although these criteria were found even in young nulliparous women, there was a significant increase in older or parous women with at least one vaginal delivery. We failed to demonstrate significant changes between the nulliparous LAM, the male LAM, and the LAM from women with prolapse and incontinence. None of the specimen showed any obvious evidence of neuropathy.

CONCLUSIONS

We have evaluated histological criteria adapted from the examination of limb muscles in the LAM of nulliparous young women. "Myogenic changes" seem to be a normal finding in the LAM. The increase of these changes with aging and parity points to mechanical stress to the LAM as the most plausible causative factor. We propose that further studies using histomorphological techniques of the pelvic floor muscle in nulliparous and parous women should clarify the potential role of our histological findings.

Study on nerve fiber density in anterior vaginal epithelium for stress urinary incontinence

The aim of this study was to determine the relationship of innervation in anterior vaginal epithelium with the etiology of stress urinary incontinence (SUI). Fifty-three biopsy specimens of the anterior vaginal epithelium were obtained from 53 subjects in control, pelvic organ prolapse (POP) and SUI groups. Routine HE staining and immunohistochemical staining for protein gene product 9.5 (PGP9.5) were performed for all specimens. PGP9.5 immunoreactivity was identified in nerve fibers and cells of the epithelium and subepitheliual connective tissue of vagina. The nerve fiber profiles of vaginal epithelium in the SUI/POP groups were significantly lower than those in the control group (P < 0.05). There was no correlation between the nerve fiber profiles and parity in SUI, POP and control groups. Decrease of nerve fiber profiles in anterior vaginal epithelium might lead to the occurrence of SUI.

Estrogen Regulates Vaginal Sensory and Autonomic Nerve Density in the Rat1

Vaginal function is strongly influenced by reproductive hormone status. Vaginal dysfunction during menopause is generally assumed to occur because of diminished estrogen-mediated trophic support of vaginal target cells. However, peripheral neurons possess estrogen receptors and are potentially responsive to gonadal steroid hormones. In the present study, we investigated whether sensory and autonomic innervation of the vagina varies among rats during the estrus phase of the estrous cycle, following chronic ovariectomy, and after sustained estrogen replacement. Relative to rats in estrus, ovariectomized rats showed a 59% elevation in nerve density, as determined using the panneuronal marker PGP 9.5. This increase persisted even after correcting for differences in vaginal tissue size, indicating true axonal proliferation after ovariectomy rather than changes secondary to altered volume. Increased total innervation after ovariectomy was attributable to increased densities of sympathetic nerves immunostained for tyrosine hydroxylase (70%), cholinergic parasympathetic nerves immunoreactive for vesicular acetylcholine transporter (93%), and calcitonin gene-related peptide-immunoreactive sensory nociceptor nerves (84%). Myelinated primary sensory innervation revealed by RT-97 immunoreactivity did not appear to be affected. Sustained 17beta-estradiol administration reduced innervation density to an extent comparable to that of estrus, implying that estrogen is the hormone mediating vaginal neuroplasticity. These findings indicate that some aspects of vaginal dysfunction during menopause may be attributable to changes in innervation. Increased sympathetic innervation may augment vasoconstriction and promote vaginal dryness, while sensory nociceptor axon proliferation may contribute to symptoms of pain, burning, and itching associated with menopause and some forms of vulvodynia.

Co-regulation of female sexual behavior and pregnancy induction: an exploratory synthesis

This paper will review both new and old data that address the question of whether brain mechanisms involved in reproductive function act in a coordinated way to control female sexual behavior and the induction of pregnancy/pseudopregnancy (P/PSP) by vaginocervical stimulation. Although it is clear that female sexual behavior, including pacing behavior, is important for induction of P/PSP, there has been no concerted effort to examine whether or how common mechanisms may control both functions. Because initiation of P/PSP requires that the female receive vaginocervical stimulation, central mechanisms controlling P/PSP may be modulated by or interactive with those that control female sexual behavior. This paper presents a synthesis of the literature and recent data from our lab for the purpose of examining whether there are interactions between behavioral and neuroendocrine mechanisms which reciprocally influence both reproductive functions.

Role of the nitric oxide-cyclic GMP pathway in regulation of vaginal blood flow

The regulatory role of nitric oxide (NO) in vaginal perfusion remains unclear. We used specific inhibitors of enzymes in the NO-cyclic GMP (NO-cGMP) pathway and investigated their effects on vaginal blood flow in the rabbit. NO synthase (NOS) activity was similar in both the proximal and distal rabbit vagina; whereas, arginase activity was 3.4-fold higher in the distal vagina. Intravenous administration of the NOS inhibitor L-NAME resulted in a 66% reduction in genital tissue oxyhemoglobin and a 53% reduction in vaginal blood flow. This attenuation occurred despite a 20-30% increase in systemic arterial pressure. The arginase inhibitor ABH caused a 2.1-fold increase in genital tissue oxyhemoglobin and 34% increase in vaginal blood flow. The guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one and the phosphodiesterase type 5 inhibitor sildenafil caused in a 37% reduction and a 44% increase in vaginal blood flow, respectively. These observations suggest that the NO-cGMP pathway is an important regulator of vaginal hemodynamics.

NEUROANATOMY OF THE HUMAN FEMALE LOWER UROGENITAL TRACT

PURPOSE

The neuroanatomy of the female lower urogenital tract remains controversial. We defined the topographical anatomy and differential immunohistochemical characteristics of the dorsal nerve of the clitoris, the cavernous nerve and the nerves innervating the female urethral sphincter complex.

MATERIALS AND METHODS

A total of 16 normal female human pelvic specimens at 14 to 34 weeks of gestation were studied by immunohistochemical techniques. Serial sections were stained with antibodies raised against the neuronal markers S-100 and neuronal nitric oxide synthase (nNOS), vesicular acetylcholine transporter, calcitonin gene-related peptide and substance P. The serial sections were computer reconstructed into 3-dimensional images.

RESULTS

Under the pubic arch at the hilum of the clitoral bodies the branches of the cavernous nerves joined the clitoral dorsal nerve to transform its immunoreactivity to nNOS positive. The cavernous nerves originated from the vaginal nervous plexus occupying the 2 and 10 o'clock positions on the anterolateral vagina and they traveled at the 5 and 7 o'clock positions along the urethra. The urethral sphincter complex was innervated by nNOS immunoreactive and nonimmunoreactive nerve fibers arising from the vaginal nervous plexus and pudendal nerve, respectively.

CONCLUSIONS

The dorsal nerve of the clitoris receives nNOS positive branches from the cavernous nerve as a possible redundant mechanism for clitoral erectile function. The urethral sphincter complex has dual innervation, which pierces into the urethral sphincter complex at different locations. The study of the neuroanatomy of the female lower urogenital tract is germane to the strategic design of female reconstructive surgery.

Sexual responsiveness in women with spinal cord injuries: differential effects of anxiety-eliciting stimulation

Sexual dysfunction is a common problem in women after spinal cord injuries (SCIs). Recently, the use of anxiety-provoking stimulation has been explored as a means of improving sexual responses in able-bodied sexually functional and dysfunctional women. In this laboratory-based study, we assessed the sexual and autonomic responses of women with SCIs with varying degrees of preservation of sympathetic innervation to their genitals to respond to anxiety-provoking audiovisual (AV) stimulation. Subjects were 45 women with SCIs and 11 able-bodied women. For purposes of analysis, SCI subjects were grouped on the basis of the degree of preservation of sensation in the T11-L2 dermatomes. Results revealed that women with low sensory scores in these dermatomes achieved higher vaginal pulse amplitude (VPA) responses to audiovisual erotic stimulation after anxiety preexposure than after neutral preexposure; however, women with SCIs and the greatest degree of preservation of sensory function in the T11-L2 dermatomes, as well as able-bodied controls, did not. Moreover, these same 2 groups of subjects had a decrease in VPA responses during baseline periods in which an anxiety-provoking video sequence was shown, but not during the neutral sequence. It is concluded that these findings are due to the proximity of sensory and autonomic neurologic elements in the spinal cord. Moreover, they demonstrate the differential effects of sympathetic stimulation on genital sexual arousal.

[Study of neural expression in vaginal mucosa of patients with urinary stress incontinence]

OBJECTIVE

The aim of our study was to investigate the histological changes of vaginal mucosa innervation in stress urinary incontinence (SUI), to determine the alteration that contributed to them.

METHODS

Biopsy specimens of anterior vaginal wall were obtained from 56 subjects during operation, which belonged to one of the 3 groups: SUI (15 cases), POP (23 cases) and asymptomatic control (15 cases). Using immunohistochemical method we could semiquantitatively determine the expression of neurofilament (NF) in vaginal mucosa as the distribution of the nerve terminals.

RESULTS

There were brown-stained nerve fibers in the lamina propria. According to the expression staging (-, +, ++, +++), the number of patients was 6, 5, 4, 0 cases in SUI group, 17, 5, 1, 0 cases in POP group, and 3, 2, 4, 6 cases in control group, respectively. There was significant difference between SUI group and control group in the expression of NF (P < 0.05) and the expression of nerve fiber had no correlation with the clinical severity and leak point pressure (LPP) in SUI group (P > 0.05). The expression of NF in POP group was also weaker than control.

CONCLUSION

The SUI group had a significant less total innervation of vaginal mucosa than asymptomatic controls, which may contribute to the pathogenesis of SUI.

Paced mating behavior in the female rat following lesions of three regions responsive to vaginocervical stimulation

The present study examines the effects of ibotenic acid lesions of the medial amygdala, the bed nucleus of the stria terminalis and the medial preoptic area on the display of paced mating behavior in female rats. Lesions of either the medial amygdala or the bed nucleus of the stria terminalis have no effect on the display of paced mating behaviors in ovariectomized, hormone-primed rats. In contrast, lesions of the medial preoptic area significantly lengthen contact-return latencies following intromissions and ejaculations and increase withdrawal from the male following intromissions. The present study demonstrates that the medial amygdala and the bed nucleus of the stria terminalis are not involved in the behavioral responses accompanying paced mating behavior, whereas the medial preoptic area is a critical component of the neural circuit mediating paced mating behavior as well as other appetitive aspects of mating.

Intravaginal administration of herpes simplex virus type 2 to mice leads to infection of several neural and extraneural sites

Female mice have been used extensively to study mucosal immunity against herpes simplex virus type 2 (HSV-2) infection of the vagina, but comparatively little is known about the spread of this virus to other tissues. Here the authors have used immunolabeling to demonstrate that HSV-2 infected the vaginal epithelium; the epithelium covering the vulva, perineum, and anal canal; and perineal hair follicles and sebaceous glands. The kinetics and basal localization of the immunolabeling indicated that the virus spread horizontally within the epithelial layer, starting in the vagina and then proceeding to the distal epithelial sites. HSV-2 also spread from the vagina to multiple neuronal sites including the paracervical ganglia (PCG), which are the major autonomic ganglia of the pelvis. The authors demonstrated both sympathetic and parasympathetic neurons in the PCG by labeling of acetylcholinesterase and tryosine hydroxlyase, and noted that infection was limited mainly or entirely to parasympathetic neurons. Infection of the PCG was correlated with the presence of virus in the autonomic ganglia in the walls of the rectum and urinary bladder, which in turn correlated with distention of these organs and retention of urine and feces. HSV-2 infection was also detected in cell bodies and axons in the lumbosacral sympathetic chain, in lumbosacral dorsal root ganglia, and in the dorsal portions of the lumbar spinal cord. Collectively, the data show that vaginal HSV-2 infection in mice leads to subsequent infection of multiple neural and epithelial sites. This information should be useful for development of a mouse model that can be used to study HSV-2 latency and for development of therapeutic vaccines to prevent recurrent infections.

New techniques in female pudendal somatosensory evoked potential testing

OBJECTIVE

The primary nerves innervating the female genitalia are the dorsal nerve of the clitoris (DNC) and the perineal nerve, which innervate the clitoris and the external genitalia/distal vagina, respectively. We describe two novel electrodiagnostic techniques for evaluating the integrity of these female genital somatosensory pathways.

SUBJECTS AND METHODS

Seventy-seven healthy women (mean age 29.3 years) were enrolled for this study. We performed DNC somatosensory evoked potentials (SEPs), stimulating through self-adhesive disk electrodes on either side of the clitoris. Perineal nerve SEPs were evoked through a vaginal probe. Cortical responses were measured through cup electrodes affixed to the scalp at Cpz and Fpz. Stimulus parameters were duration 0.1 ms, frequency 4.1 Hz, filters 5-5,000 Hz, at three times sensory threshold.

RESULTS

DNC and perineal nerve SEPs from both the right and left sides were reproducible and easily discerned. The mean P1 latencies were: right DNC 39.4 ms (SD 2.8 ms), left DNC 39.3 ms (SD 3.3 ms), right perineal nerve 37.8 ms (SD 3.4 ms), left perineal nerve 37.6 ms (SD 3.1 ms). We recorded SEP responses from 90 to 92% of subjects for the DNC, and 69% for the perineal nerve.

CONCLUSIONS

We are able to evoke somatosensory potentials from the four primary somatic nerves that mediate female genital cutaneous sensation. In healthy subjects, the DNC responses are robust and maintain laterality. The perineal nerve responses are less consistently obtained, but when recorded, are easily discerned. These preliminary data provide a foundation from which to study female genital innervation, particularly as it applies to sexual function.

[Modern algorithm for treating pudendal neuralgia: 212 cases and 104 decompressions]

Clinical signs and symptoms of the pudendal neuralgia are very rich, with a great individual variability. The clinical diagnosis is difficult. It is confirmed or invalidated by the electrophysiologicals tests. Since October 1998 patient selection has been possible using a diagnosis score. Over a four-year period, the diagnosis of pudendal neuralgia was confirmed by electrophysiological investigations in 212 subjects. We rejected 12 patients because of a radiculo-medullary organic etiology. We only describe here cases of women with a peripheral pudendal nerve injury (200 patients). Thirty-eight neuropathies free of canal symptoms (obstetrical, post-traumatic...) were treated by infiltration therapy. The study of a total of 162 canal syndromes showed prevalent injury at the sacro-spino-tuberal ligamental grip which was observed in 68% of the cases, compared to the Alcock canal which was present in only 20% of the cases. One hundred four of these patients underwent surgical decompression via a trans-ischio-rectal approach after negative results of the infiltration therapy. We report here the surgical methodology, the post-op follow-up and the results, which appear quite successful: after one year 86% of the subjects are symptom-free or with a significant reduction of pain.

Total mesometrial resection: High resolution nerve-sparing radical hysterectomy based on developmentally defined surgical anatomy

Total mesometrial resection (TMMR) is characterized by: i). the en bloc resection of the uterus, proximal vagina, and mesometrium as a developmentally defined entity; ii). transection of the rectouterine dense subperitoneal connective tissue above the level of the exposed inferior hypogastric plexus; and iii). extended pelvic/periaortic lymph node dissection preserving the superior hypogastric plexus. Since July 1998 we have studied prospectively the outcome in patients treated with TMMR for cervical carcinoma FIGO stages IB, IIA, and selected IIB. By July 2002, 71 patients with cervical cancer stages pT1b1 (n = 48), pT1b2 (n = 8), pT2a (n = 3), pT2b (n = 12) had undergone TMMR without adjuvant radiation. Fifty-four percent of the patients exhibited histopathologic high risk factors. At a median observation period of 30 months (9-57 months) two patients relapsed locally, two patients developed pelvic and distant recurrences and two patients only distant recurrences. Three patients died from their disease. Grade 1 and 2 complications occurred in 20 patients, no patient had grade 3 or 4 complications. No severe long-term impairment of pelvic visceral functions related to autonomic nerve damage was detected. Based on these preliminary results, we believe TMMR achieves a promising therapeutic index by providing a high probability of locoregional control at minimal short and long-term morbidity.