Ultrastructural and Quantitative Study of Clitoral Cavernous Tissue from Living Subjects

Stereological comparison of smooth muscle, collagen, and elastic fibers of the clitoris and glans penis in young adults

OBJECTIVE

To compare the collagen, elastic fibers, and smooth muscle content of the clitoris and the glans penis in young adults.

MATERIALS AND METHODS

The clitoris and the glans penis of six women and six men (mean age 25±3) who died as a result of accidents were excised. The samples were placed under a formaldehyde solution and histologically processed. Masson's trichrome and Weigert's resorcin-fuchsin stain was used to highlight the elastic fibers, smooth muscle, and collagen. Stereological analysis was conducted in 5 random fields of 5 slides for each sample. For statistical analysis, the unpaired t-test was used to compare values between groups, and a value of P<0.05 was considered as significant for all analyses.

RESULTS

Stereology revealed a mean smooth muscle content of 35.84±6.46% and 31.64±4.74% for the clitoris and glans penis, respectively, while it also revealed collagen content of 26.11±7.41% and 28.44±3.55% and elastic fibers content of 24.12±4.34% and 30.97±6.13% for the clitoris and glans penis, respectively. The statistical analysis showed no significant differences between them.

CONCLUSION

Regardless of anatomical differences, the volumetric density of collagen, elastic fibers, and smooth muscle were similar for the clitoris and glans penis in young adults, a feature possibly explained by their embryology.

Morphological changes in the anterior vaginal wall caused by aging: a scanning electron microscopy study

INTRODUCTION AND HYPOTHESIS

Collagen is a protein that confers robustness and resilience to several tissues. In the female reproductive system, collagen plays a critical role in maintaining the health and function of the vaginal walls. Aging leads to collagen reduction, which may cause vaginal dryness, irritation, and prolapse. We aim to analyze the structure and profile of collagen in the anterior vaginal wall of healthy pre-menopausal (pre-M) and post-menopausal (post-M) women under a scanning electron microscope (SEM).

METHODS

Fragments of the anterior vaginal wall were collected and processed for light and scanning electron microscopy. Histological preparations were performed at first with Weigert's resorcin-fuchsin stain. Decellularized preparations were conducted, and the specimens were placed under an SEM to allow observation of the 3D organization of collagen.

RESULTS

Decellularized preparations of the pre-M specimens showed a vaginal wall with an irregular subepithelial layer, organized with ECM projections. The subepithelium evidenced the network of collagen fibrils, which seemed to support the epithelium as a basal layer. In specimens of post-M, a fusion of a network of fibrils from different direction axes was evidenced, with plate formation observed in the subepithelial plane, disfiguring the structural organization of fibrils.

CONCLUSIONS

Older specimens showed a remodeling of collagen organization in comparison with younger samples of the anterior vaginal wall.

Analysis of hsa-miR-19a-3p and hsa-miR-19b-3p modulation and phosphodiesterase type 5 expression in the vaginal epithelium of premenopausal women with genital arousal disorder

BACKGROUND

Few studies have investigated the role of the phosphodiesterase type 5A (PDE5A) isoenzyme in female genital tissue disorders, exclusively taken from cadavers, as well as the epigenetic mechanisms responsible for the regulation of PDE5A levels.

AIM

The aim was to study the in vivo association between microRNA (miRNA) expression and the expression levels of PDE5A in women with female genital arousal disorder (FGAD) compared with healthy women.

METHODS

Premenopausal women affected by FGAD (cases) and sexually healthy women (control group) underwent microbiopsy of the periclitoral anterior vaginal wall for the collection of tissue samples. Computational analyses were preliminarily performed in order to identify miRNAs involved in the modulation of PDE5A by using miRNA-messenger RNA interaction prediction tools. Differences in the expression levels of miRNAs and PDE5A were finally investigated in cases and control subjects by using the droplet digital polymerase chain reaction amplification system and stratifying women considering their age, number of pregnancies, and body mass index.

OUTCOMES

Expression levels of miRNAs were able to target PDE5A and the tissue expression in women with FGAD compared with healthy women.

RESULTS

The experimental analyses were performed on 22 (43.1%) cases and 29 (56.9%) control subjects. Two miRNAs with the highest interaction levels with PDE5A, hsa-miR-19a-3p (miR-19a) and hsa-miR-19b-3p (miR-19b), were identified and selected for validation analyses. A reduction of the expression levels of both miRNAs was observed in women with FGAD compared with the control subjects (P < .05). Moreover, PDE5A expression levels were higher in women with FGAD and lower in women without sexual dysfunctions (P < .05). Finally, a correlation between body mass index and the expression levels of miR-19a was found (P < .01).

CLINICAL IMPLICATIONS

Women with FGAD had higher levels of PDE5 compared with control subjects; therefore, the administration of PDE5 inhibitors (PDE5 inhibitors) could be useful in women with FGAD.

STRENGTHS AND LIMITATIONS

The strength of the current study was to analyze genital tissue obtained in vivo from premenopausal women. A limitation was to not investigate other factors, including endothelial nitric oxide synthetases, nitric oxide, and cyclic guanosine monophosphate.

CONCLUSION

The results of the present study indicate that the modulation of selected miRNAs could influence PDE5A expression in genital tissues in healthy women or in those with FGAD. Such findings further suggest that treatment with PDE5 inhibitors, as a modulator of PDE5A expression, could be indicated for women with FGAD.

Sexual dysfunction in patients with spinal cord lesions

Many aspects of sexuality can be disrupted following a spinal cord lesion (SCL). It can alter an individual's self-esteem and body image, interfere with positioning and mobility, introduce unexpected problems with incontinence and spasticity, decrease pleasure, and delay orgasm. Sexual concerns in men can involve erectile function, essential for intercourse, ejaculation function, necessary for fertility, and the ability to reach orgasm. In women they can involve concerns with vaginal lubrication, genital congestion, and vaginal infections, which can all go unnoticed, and orgasm, which may be lost. All of these concerns must be addressed during rehabilitation as individuals with SCL continue to live an active sexual life, and consider sexuality among their top priority for quality of life. This chapter describes the impact of SCL on various phases of men's and women's sexual responses and on various aspects of sexuality. Treatments are described in terms of what is currently available and what is specific to the SCL population. New approaches in particular for women are described, along with tips from sexual counseling which consider an overall approach, taking into account the primary, secondary, and tertiary consequences of the SCL on the individual's sexuality. Throughout the chapter, attempts are made to integrate neurophysiologic knowledge, findings from the literature on SCL, and clinical experience in sexual rehabilitation.

Characterization of the vasculature supplying the genital tissues in female rats

INTRODUCTION

The internal pudendal arteries are the key resistance vessels controlling the peripheral circulatory component of sexual responses in both male and females. Previous studies in the male rat demonstrated that this vessel has markedly heightened susceptibility to vascular damage compared with other vessels in the body. Evidence suggests that the female may also be susceptible to vascular pathologies contributing to sexual dysfunction.

AIM

The aim of this study is to characterize the anatomical, morphological, and functional properties of the pudendal artery in female rats.

METHODS

The pelvic arteries in young Sprague-Dawley female rats were dissected to generate a composite representation of the vascular gross anatomy. Morphometry was performed on perfusion-fixed pudendal arteries whereas others were mounted in a wire myograph to assess responses to vasoactive drugs. These measures were contrasted with a previous study examining male rats.

MAIN OUTCOME MEASURES

Outcome measures used are gross anatomy, lumen diameter, wall thickness, cross-sectional area, and contractile responses in the internal pudendal artery.

RESULTS

The gross anatomy of the pudendal artery in female rats appears to parallel that found in male rats, acting as the primary feeder vessel of the clitoral, labial, and vaginal tissue. Compared with the male rat, the female pudendal artery has a smaller lumen diameter (169 ± 5.7 vs. 303 ± 13.8 µm), wall thickness (14 ± 0.7 vs. 47 ± 2.2 µm), and cross-sectional area (8 ± 0.4 vs. 52 ± 3.4 × 103 µm(2) ). These structural differences also translate into a decreased contractile capacity of the pudendal arteries from female rats vs. male rats (8.1 ± 2.7 vs. 20 ± 1.4 mN).

CONCLUSIONS

Although the gross anatomical features of the vasculature tree supplying the genital tissue in male and female rats appear to have similarities, the tissue-specific properties of the vessel itself have a very different structure-function balance. We hypothesize that this discordance likely reflects the very different sex-specific roles of this vessel in regulating blood flow during arousal.