目的 观察不同浓度茶色素(Tea pigment，TP)溶液在低钙和高钙条件下对离体蟾蜍心肌收缩力和心率的影响。方法 50只蟾蜍随机分为正常任氏液组，任氏液+茶色素组，低钙任氏液+茶色素组，高钙任氏液+茶色素组。采用斯氏法制备离体蛙心灌流标本。正常任氏液组离体蟾蜍心脏只灌流任氏液，任氏液+茶色素组在离体蟾蜍心脏灌流任氏液中加入茶色素溶液，低钙任氏液+茶色素组在离体蟾蜍心脏灌流低钙任氏液中加入茶色素溶液，高钙任氏液+茶色素组在离体蟾蜍心脏灌流高钙任氏液中加入茶色素溶液。通过蟾蜍心室外加药，利用心室收缩波动，心室吸收药物的方法给药，心室外容积固定为1.0 mL，分别以不同浓度的茶色素进行灌流，每次加入茶色素后记录40 min。应用BL-420F生物机能实验系统记录离体蟾蜍心肌收缩曲线，并进行心肌收缩力和心率的统计学分析。结果 在低钙条件下，灌流茶色素溶液浓度为50 μg·mL-1时，心肌收缩力开始增强，差异有统计学意义(P < 0.05)；在高钙条件下，灌流200 μg·mL-1茶色素时，心肌收缩力受到抑制，差异有统计学意义(P < 0.01)。结论 在低钙任氏液条件下，一定浓度的茶色素对离体蟾蜍心脏活动有明显的兴奋作用，而在高钙任氏液条件下则茶色素对心肌收缩力有明显的抑制作用。

Objective To observe the effect of different concentrations of tea pigments on isolated toad myocardial contraction under lower calcium condition and under higher calcium condition. Methods Fifty toads were randomly divided into Ringer solution control group，normal Ringer solution+ tea pigments group，lower calcium Ringer solution +tea pigments group，and higher calcium Ringer solution +tea pigments group. The perfusion specimens of isolated frog heart were prepared by Si's method. The isolated frog hearts in the four groups were given reperfusion with the corresponding solution according to the grouping method. The toad ventricle muscle contraction wave was recorded for 40 min after tea pigments administration outside the ventricle with the fixed volume of 1.0 mL. The myocardial contractility and heart rate were analyzed statistically by application of BL-420F biological and functional experimental system. Results Under lower calcium condition，myocardial contractility started to increase significantly after reperfusion with tea pigments at 50 μg·mL-1(P < 0.05). Under higher calcium condition，myocardial contractility was inhibited significantly after reperfusion with tea pigments at 200 μg· mL-1(P < 0.01). Conclusion Isolated toad cardiac activity is increased obviously by certain concentration of tea pigments under lower calcium condition，and then is inhibited by certain concentration of tea pigments under higher calcium condition.

R285.5

国家自然科学基金项目(81200155)；2011年辽宁省大学生科技创新项目。