BOTULINUM TOXIN-A (BTA) INDUCED ERECTILE PENILE, THROUGH RELAXATION OF THE CORPUS CARVENOUS SMOOTH MUSCLE, IN A RAT MODEL
Messina, L(1); Andrade, E(1); Andrade, P(1); Cortez, Í(1); Paranhos, M(1); Leite, K(1); Villanova, F(1); Srougi, M(1)
(1)Faculdade de Medicina da Universidade de São Paulo, Departamento de Urologia, Setor de Medicina Sexual.
Introduction and Objective: The botulinum toxin-A (BTA) is an endopeptidase which blocks acetylcholine release at the neuromuscular junction and with the increasing interest of your application in the lower urinary tract, we investigated the BTA effects on the Wistar rats corpus cavernous and also as judged by histological alterations.
Methods: A total of 30 Wistar rats were divided into three groups and treated with injection into the corpus cavernous. In Group I (N = 10): 0,5 ml of the saline solution was injected. In Group II (N = 10): 0,5 ml of the saline solution with 10 U of BTA was injected. In Group III (N = 10): 0,5 ml of the saline solution with 10 micromoles (µM) of prostaglandin E1 (PGE1) was injected intracavernous. After 36 hours of injection, the groups I and II, the following parameter was studied: histological features of the corpus cavernous; being compared with the group III, being penile tissue removed 2 hours after injection intracavernous.
Results: The group treated with the BTA, showed a significantly increase of the penile size, similar of the group that injected with PGE1, when compared with the group that only received the saline solution (p<0.05, group II and III vs group I). In histological analysis, were showed smooth muscle relaxation and increase intracavernosal blood in the groups II and III.
Conclusions: These results suggested that intracavernosal BTA injection induces erection penile in rats, that is similar of the PGE1 effects. Therefore, the mechanism of action of BTA should be better elucidated, analyzing if blocks acetylcholine release at the neuromuscular junction, have any action in the smooth muscle relaxation of the corpus cavernous.
