摘要
Aim: To investigate the effects of androgen on penile erection through the reflex arc and penile corpus cavernosum,and study the respective roles of testosterone (T) and dihydrotestosterone (DHT) in penile erection in rats. Methods:Male Sprague-Dawley rats were castrated and implanted with silastic brand silicone tube containing T or DHT, with orwithout daily injections of a 5α-reductase inhibitor, MK-434. The penile reflex, erectile response to electrical stimula-tion (ES) of the cavernous nerves and penile nitric-oxide synthase (NOS) activity were observed under varying andro-genic status. Results: Penile reflex erection in the rat was, on the whole, related to serum T levels though the numberof glans engorgements was not. The number of cups and flips was significantly decreased by castration, and restoredto the control level by T supplementation. Erectile response to ES and NOS activity in penile tissue was also related toserum T level. T administered together with a 5α-reductase inhibitor no longer restored the number of reflex erection,erectile responses to ES and NOS activity in the corpus cavernosum. Conclusion: Androgen influenced the penile re-flex arc, corpus cavernosum, and the perineal striated muscles. In reflex erection, erectile response to ES and penileNOS activity in the rat, T seems to be first converted to DHT, the more active androgen modality. (Asian J Androl1999 Dec; 1: 169-174)
Aim: To investigate the effects of androgen on penile erection through the reflex arc and penile corpus cavernosum,and study the respective roles of testosterone (T) and dihydrotestosterone (DHT) in penile erection in rats. Methods:Male Sprague-Dawley rats were castrated and implanted with silastic brand silicone tube containing T or DHT, with orwithout daily injections of a 5α-reductase inhibitor, MK-434. The penile reflex, erectile response to electrical stimula-tion (ES) of the cavernous nerves and penile nitric-oxide synthase (NOS) activity were observed under varying andro-genic status. Results: Penile reflex erection in the rat was, on the whole, related to serum T levels though the numberof glans engorgements was not. The number of cups and flips was significantly decreased by castration, and restoredto the control level by T supplementation. Erectile response to ES and NOS activity in penile tissue was also related toserum T level. T administered together with a 5α-reductase inhibitor no longer restored the number of reflex erection,erectile responses to ES and NOS activity in the corpus cavernosum. Conclusion: Androgen influenced the penile re-flex arc, corpus cavernosum, and the perineal striated muscles. In reflex erection, erectile response to ES and penileNOS activity in the rat, T seems to be first converted to DHT, the more active androgen modality. (Asian J Androl1999 Dec; 1: 169-174)
