人参三醇组皂甙对大鼠心室肌细胞L型、T型、B型钙通道的阻滞作用

CALCIUM CHANNEL BLOCKADE ACTION OF PANAXATRIOL SAPONINS ON THE L TYPE, T TYPE AND B TYPE CALCIUM CHANNELS OF CULTURED RAT CARDIOMYOCYTES

分离Wistar大鼠乳鼠的心室肌细胞,向培养基中分别加入人参三醇组皂甙300μg/ml,钙通道阻滞剂异博定37.5μg/ml或钙通道激动剂BAY K 8644 5μmol/L。用斑片钳的连细胞电压钳法,记录加药前后L、T、B三型钙通道的单通道活动。确证了人参三醇组皂甙的钙通道阻滞作用,并揭示其作用机理在于使钙通道的开放时间缩短与开放概率减少。

Wistar rat ventricular myocardiocytes were isolated. Panaxatriol saponins (PTS) 300μg/ml, calcium channel blocker verapamil 37. 5μg/ml or calcium channel activator BAY K 8644 5μmmol/L were added into the bath solution separately. The single channel activities of L, T and B type calcium channels were recorded before and after administration, using the voltage patch-clamp technique in cell-attached configuration. The calcium channel blockade effect of PTS was exactly demonstrated. It was disclosed that the mechanism involved decrease in both the open time and the open-state probability of the calcium channel.