Osthole is a libido stimulator: researchers investigate the cavernosal relaxant effect of osthole, has been long used in China as a herbal medicine to improve male sexual dysfunction. The data suggested that osthole posseses a relaxant effect on rabbit corpus cavernosal tissues which is attributable to the release of NO from sinusoidal endothelium and to the potentiation of the cGMP and/or cAMP signal mediating relaxation of cavernosal smooth muscle by inhibiting phosphodiesterase.