Objective: To investigate the effects of chuanxiongzine on the relaxation of isolated rabbit corpus cavernosum tissues.
Methods: Observations were made on the relaxing effect of chuanxiongzine on phenylephrine (PE)-precontracted corpus cavernosum and cavernosal strips preincubated with L-NAME, and ODQ, using endothelium removal and experimental method of smooth muscle strips. The effect of chuanxiongzine on cAMP and cGMP levels in corpus cavernosum was measured by 125I radioimmunoassay.
Results: Chuanxiongzine had concentration-dependent relaxing effect on the cavernosal muscle contraction induced by PE (EC50 1.58 x 10(-4) mol/L). This relaxing effect was partially antagonized by ODQ and not blocked by L-NAME or endothelium removal. In PE-precontracted cavernosal strips, chuanxiongzine induced relaxation accompanied with an increase in cAMP and cGMP levels.
Conclusion: Chuanxiongzine was effective in relaxing cavernosal muscle precontracted by PE in vitro. And its relaxing effect may be enhanced by increasing cGMP and cAMP levels in the corpus cavernosum.