人參皂中的非主要皂成份引發離體大白兔陰莖海棉組織產生舒張反應

Non Major Ginsenosides Contribute to the Relaxation of Panax Ginseng in Rabbit Corpus Cavernosum

本實驗評估人參總皂（crude ginseng saponin ）、總皂次萃取物（subfractions, F1 ～F9 ）、及皂標準品（Rg1, Rb1, Re ）在離體大白兔陰莖海綿組織的舒張活性。結果顯示人參總皂　可以有效舒張phenylephrine （3 ×10-6 M ）預收縮的陰莖海綿體，一半有效濃度（EC50 ）為3.65 ± 0.27mg/ml ；相反地，皂標準品（Rg1, Rb1, Re ）在相當劑量範圍下，則完全不影響海綿體張力，此結果暗示人參總皂中的三個主要皂（Rg1, Rb1, Re ）並非是舒張海綿體的主要活性成份。繼續以管柱分離總皂得到9 個部份（F1 ～F9 ），分別呈現不同程度的海綿體舒張活性, 其中以F2 的作用最強（EC50 = 0.49 ± 0.03 mg/ml ）、且顯著強於人參總皂。以上結果暗示F2 可能有機會作為治療陽痿的陰莖內注射用藥，但在臨床使用前必須再評估其組成、在活體動物的實驗結果以及是否可作為口服投藥.The corporal relaxant effects of total ginsenosides and nine subfractions (F1~F9) separated from it were evaluated in the rabbit corpus cavernosal strips in vitro . In the tissues precontracted by phenylephrine (PE, 3°—10-6 M), ginsenosides induced a dose-dependent (from 1 to 20 mg/ml) relaxing effect on rabbit corpus cavernosal strips with an EC50 of 3.65± 0.27 mg/ml. Three pure ginsenoside - Rg1 , Rb1 , and Re, at optimal dosages, do not affect the vascular tone at al in PEprecontracted corpus cavernosum. Total ginsenosides was further subfractionated by column chromatography and obtained nine fractions (F1~F9). Among them, F2 (0.1~5 mg/ml) displayed the most potent relaxing activity and turned out to be more effective (EC50 =0.49± 0.03 mg/ml) than total ginsenosides. Additionally, TLC analysis revealed that F2 contained some other components different from Rg1 , Rb1 and Re. These findings suggest none of Rg1 , Rb1 and Re contributes to the beneficial effect of total ginsenosides. In summary, F2 may possibly be used as a drug for intracavernosal injection therapy of impotence. However, further separation and identification the components of F2 and in vivo study are needed before clinical use in an oral form.