荭草苷对缺血缺氧心肌的保护作用

目的 研究荭草苷对缺血缺氧心肌的保护作用.方法 采用小鼠常压耐缺氧实验、夹闭气管小鼠心电消失时间、豚鼠离体心脏的冠脉流量、花生四烯酸诱导的家兔血小板聚集和垂体后叶素所致大鼠心肌缺血模型,观察荭草苷对缺血缺氧心肌的保护作用.结果 荭草苷(1,2,4 mg/kg)均能显著延长小鼠常压耐缺氧条件下的存活时间,延长夹闭气管小鼠心电消失时间,荭草苷(3,10,30 μmol/L)明显抑制花生四烯酸诱导的家兔血小板聚集并能增加豚鼠离体心脏的冠脉流量.荭草苷(0.75,1.5,3.0 mg/kg)能拮抗垂体后叶素引起的心电图变化.结论 荭草苷对缺血缺氧心肌具有明显保护作用,其效应与剂量呈相关性.

Protective effects of orientin on myocardial ischemia and hypoxia in animal models

OBJECTIVE: To study the protective effects of orientin against myocardial ischemia and hypoxia in rats. METHODS: The protective effect of orientin against myocardial ischemia and hypoxia was observed in mice by recording their survival time under closed normobaric hypoxia and time of cardiac electric disappearance due to trachea clamping, in rabbits by evaluating arachidonic acid (AA)-induced blood platelet aggregation, in guinea pigs by measuring the coronal flow in the isolated heart and in SD rats with myocardial ischemia induced by pituitrin injection. RESULTS: Orientin (1, 2, 4 mg/kg) significantly prolonged the survival time of mice under closed normobaric hypoxia and the gasping duration induced by decapitation. Orientin at concentrations of 3, 10, and 30 micromol/L also inhibited AA-induced blood platelet aggregation in rabbits and increased coronal flow in the isolated heart of guinea pigs. At 0.75, 1.5, and 3.0 mg/kg, orientin significantly antagonized pituitrin-induced ECG changes. CONCLUSION: Orientin may offer protection against myocardial ischemia and hypoxia in animal models in dose-dependent fashions.