Effects of testosterone supplementation on prevention of age-related penile remodeling

Erectile dysfunction develops among 46.2% of men between 40 and 70 years. Studies demonstrated substitution on detrusor muscle by collagen due testosterone deprivation. It is clear the correlation among aging and oxidative stress, accelerating apoptosis process in many tissues. This study aims to demonstrate the collagen substitution over the muscle fibers on muscle structure of rat's penis and the effects of testosterone supplementation. Sixteen senescent Wistar rats were divided into two groups: treatment (receiving standard supplementation testosterone dose) and control (receiving equivalent saline solution). Testosterone was dosed on D0 and D56 of study. All penises were prepared with picrosirius colored histology; stereology was applied to determine the volumetric density of collagen fibers (Vv). Analysis of variance demonstrated testosterone group's replacement therapy to be effective, while the androgenic decline continued by the time of experiment in control group (p < 0.05). Testosterone group had Vv of 20.6%, lower than control group (47.8%); t-test (p < 0.001). Pearson's correlation demonstrated an inverse correlation between the Vv and testosterone's levels (p < 0.001). This is a pioneer study on demonstration of structural alterations over the cavernous corpora muscle caused by deprivation of testosterone on elderly rat. These finding implicate that the testosterone levels can influence, not only the libido, but also the erectile function.