ED 07. In vitro and in vivo relaxation effects of Korean ginseng berry extract (GB0710) on corpus cavernosum Smooth Muscle

Korean red ginseng (KRG; Panax ginseng) can be used to treat male erectile dysfunction (ED). Korean ginseng berry (KGB) extract may have a similar effect to KRG on male potency. To determine the efficacy of KGB extract on ED, the effects of KGB extract were evaluated both in vitro and in vivo. In in vitro experiments, strips of rabbit corpus cavernosum smooth muscle (CCSM) were prepared and were precontracted by phenylephrine (PHE) in an isotonic chamber. In in vivo experiments, the KGB extract was administrated to rats orally, and the intracavernosal pressure (ICP) was measured after stimulation of cavernous nerves in the rat. In smooth muscle cell cultures, intracellular nitric oxide (NO) production was evaluated after treatment with KGB extract (GB0710). In in vitro experiments, the relaxation effects of various extracts of KRG and KGB on precontracted rabbit CCSM were evaluated. In in vivo experiments, ICP was measured in rats. Intracellular NO production in smooth muscle cells was evaluated. Various forms and constituents of KRG extract and KGB extract had dose-dependent relaxation effects on precontracted rabbit CCSM. Among the KGB and KRG extracts, the KGB extract GB0710 had the most potent relaxation effect. This relaxation effect was inhibited by pretreatment of muscle strips by deendothelialization, methylene blue, pyrogallol, NW-nitro-Larginine (L-NNA), or 1H-[1,2,4] oxadiazolo-[4,3-a] quinoxalin- 1-one (ODQ). Furthermore, administration of GB0710 increased ICP in a rat in vivo model in both a dose-and durationdependent manner. Intracellular NO production in human microvascular endothelial cells was induced by GB0710 and was inhibited by NG-monomethyl-L-arginine (L-NMMA). GB0710 had a greater relaxation effect on rabbit CCSM than KRG extract and increased ICP in a rat model in both a doseand duration-dependent manner. This relaxing effect might be mediated by endothelium-derived relaxing factor (EDRF) and NO production.