Long-Term Oral Administration of 5α-Reductase Inhibitor Attenuates Erectile Function by Inhibiting Autophagy and Promoting Apoptosis of Smooth Muscle Cells in Corpus Cavernosum of Aged Rats

In 2013, a study involving 30 aged male rats examined the impact of long-term 5α-reductase inhibitor (5ARI) treatment on erectile function and penile structure. The rats were treated for 16 weeks, resulting in significantly reduced erectile function, decreased corpus cavernosum and prostate weight, and lower dihydrotestosterone levels. Histological and molecular analyses revealed a decrease in smooth muscle, an increase in collagen, reduced endothelial nitric oxide synthase expression, less autophagy, and more apoptosis in the cavernous smooth muscle cells. These findings suggest that androgens like dihydrotestosterone are important for maintaining the health of erectile tissues, and that long-term 5ARI use could negatively affect erectile function by disrupting the balance between autophagy and apoptosis in these tissues. The study highlights the need for further research into the long-term effects of 5ARIs on erectile function, especially in older men.