[The effects of testosterone undecanoate on relaxation of rat corpus cavernosum smooth muscle in vitro].

Objectives: To investigate the role of Undecanoate (Andriol), as a kind of testosterone, in regulating the relaxation of isolated rat corpus cavernosum in vitro.

Methods: The castrated rats were given high and low dosage Andriol respectively, compared with intact and castrated rats. After treatment of 4 weeks, the corpora cavernosa were cut, trimmed as to strips. Norepinephrine(NE) was added to contract each of the tissue strips. Next, sodium nitroprusside(SNP), electric functional stimulation(EFS) were used to relax the strips. Percent relaxations were examined.

Results: High-dose Andriol(20 mg/kg) was significantly effective to castrated rats on percent relaxation induced by 10(-3) mol/L SNP and EFS. Low-dose Andriol(10 mg/kg) was also effective to relax strips induced by 10(-3) mol/L SNP. According to statistics, the differences were significant (P < 0.01).

Conclusions: The percent relaxations of castrated rats were increased after taking Andriol, and it could increase the relaxation of corpara cavernosa.