三七茎叶皂苷对麻醉犬急性心肌缺血的保护作用

目的:研究三七茎叶皂苷(PNSSL)对麻醉犬急性心肌缺血的保护作用。方法:采用结扎冠状动脉前降支的方法,造成犬急性实验性心肌缺血模型;超声多普勒方法测定心肌血流量;用心外膜电图描记和硝基蓝四唑(N-BT)组织化学染色方法计算心肌缺血程度及梗死面积;放射免疫法测定血浆内皮素(ET)和血栓烷素B₂(TXB₂)的含量。结果:PNSSL能明显减轻由心外膜电图标测的心肌缺血程度;缩小经N-BT染色所显示的梗死区;显著增加缺血心脏的心肌血流量;对心肌缺血及心肌梗死引起的血浆ET和TXB₂的含量有明显抑制作用。结论:PNSSL对犬急性心肌缺血和心肌梗死有明显的保护作用,可能与抑制ET,TXA₂的释放,增加心肌血流量,从而改善受损心脏的功能等机制有关。

Protective effects of saponines of stem and leaf of Panax notoginseng on acute myocardial ischemia in anaesthetic dogs

OBJECTIVE: To study the protective effects of saponines of stem and leaf of Panax notoginseng (PNSSL) on acute myocardial ischemia in anaesthetic dogs. METHOD: The acute ischemia models were made by ligation of left anterior descending (LAD) artery. The myocardial blood flow (MBF) was determined by ultrasonic doppler. The experiments adopted epicardiogram mapping to measure the scope and degree of myocardial ischemia, quantitative histologic assay (nitroblue tetrazolium, N-BT stain) to determine the size of myocardial infarction. And the endothelin (ET) and thromboxane B2 (TXB2) were measured by radioimmunological assay. RESULT: PNSSL was showed to obviously alleviate the degree of myocardial ischemia (sigma-ST) and narrow the ischemic area indicated by N-BT staining. In addition, PNSSL could increase the MBF of ischemia section. And the treatment could inhibit the ET and TXB2 release induced by ischemia and infarction. CONCLUSION: PNSSL demonstrated to attenuate the damage subjected to myocardial ischemia and infarction, which may be due to its function of inhibiting the ET and TXA2 release, increasing the MBF, and then improving the damaged cardiac function.