葛根提取物抗心肌缺血机制的初步试验研究

目的初步探讨抗心肌缺血药物葛根提取物主要作用机制和药效，为进一步药物筛选提供依据。方法分别采用正常和负荷异丙肾上腺素小鼠常压耐缺氧试验、垂体后叶素致大鼠心肌缺血试验、血瘀大鼠试验、异丙肾上腺素致大鼠心肌损伤试验，考察葛根提取物对心肌耗氧量、扩张血管、活血、保护心肌作用。结果葛根提取物不能延长正常小鼠常压耐缺氧的存活时间（P〉0．05）；4．8g生药／kg能显著延长异丙肾上腺素负荷小鼠常压耐缺氧的存活时间（P〈0．05）；9．6g生药／kg能显著减少垂体后叶素致大鼠J点的位移（P〈0．05）；19．2，9．6，4．8g生药／kg对异丙肾上腺素所致大鼠心肌损伤后引起的乳酸脱氢酶（LDH）、肌酸激酶（CK）活性的增高有显著降低作用（P〈0．05）；对肾上腺素一冰浴致大鼠血瘀各指标未见明显改善（P〉0．05）。结论葛根提取物具有一定的扩张血管、降低心肌耗氧量和保护心肌细胞的作用，活血化瘀作用不强，未见有明显的量效关系。对心肌的耗氧量存在双向调节。

Preliminary Experimental Study on Anti- Myocardial Ischemia Mechanism of Pueraria Extract

Objective To preliminarily determine the main action mechanism and efficacy of anti- myocardial ischemic drug pueraria ex- tract to provide basis for further screening. Methods The hypoxia tolerance test at the ordinary pressure on normal and isoproterenol loaded mice, the pituitrin induced myocardial ischemia test in rats, the blood stasis tests in rats and the isoproterenol induced myocar- dial injury test in rats were separately adopted to investigate the effects of pueraria extract on myocardial oxygen consumption, dilation of blood vessels, promoting blood circulation and protecting myocardial function. Results The pueraria extract could not extend the sur- vival time of hypoxia tolerance at the ordinary pressure in normal mice（ P〉0. 05）;4. 8g crude drug/ kg could significantly prolong the survival time of hypoxia tolerance at the ordinary pressure in isoproterenol loaded mice（P〈 0.05）; 9.6g crude drug/kg could sig- nificant]y reduce pituitrin induced J point displacement（P 〈0.05）; 19.2,9.6,4. 8g crude drug/kg could significantly reduce the lactate dehydrogenase（LDH）, creatine kinase（CK） activity increase caused by isoproterenol induced myocardial injury in rats at the dose of（P〈 0.05）; a11 indexes of blood stasis caused by adrenaline- ice bath had no significant improvement（ P 〉 0.05）. Conclusion Pueraria ex- tract has a certain effect of dilating blood vessels, reducing myocardial oxygen consumption and protecting myocardial cells, but the effect of activating blood circulation is not strong, no obvious dose- effect relationship is found, which has a two- way adjustment on myocar- dial oxygen consumption.