In vitro and in vivo evaluation of tissue-cultured mountain ginseng on penile erection

Background: Progressed tissue culture techniques have allowed us to easily obtain mass products of tissue-cultured mountain ginseng over 100 yr old (TCMG-100). We investigated the effects of TCMG-100 extract on erectile function using in vitro and in vivo studies. Methods: To examine the relaxation effects and mechanisms of action of TCMG-100 on rabbit cavernosal strips evaluated in an organ bath. To investigate the long-term treatment effect of TCMG-100, 8-wk administration was performed. After administration of TCMG-100, intracavernosal pressure, cyclic guanosine monophosphate and nitric oxide (NO) levels of cavernosal tissue, serum testosterone level, histological observation of collagen fiber, endothelium, smooth muscle cell, and transforming growth factor-${\beta}1$ were investigated. Results: TCMG-100 extract displayed dose-dependent relaxation effects on precontracted rabbit corporal smooth muscle. The TCMG-100-induced relaxation was significantly reduced by removing the endothelium, and treatment with an NO synthase inhibitor or NO scavenger. Eight weeks of TCMG-100 administration increased intracavernosal pressure in a rat model. The levels of cyclic guanosine monophosphate and NO in the corpus callosum and serum testosterone level were also increased by TCMG-100 treatment. Furthermore, histological evaluation of collagen, smooth muscle, and endothelium showed increases in endothelium and smooth muscle, and a decrease in transforming growth factor-${\beta}1$ expression. Conclusion: These relaxation effects on corporal smooth muscle and increased erectile function suggest that TCMG-100 might be used as an alternative herbal medicine to improve erectile function.