中药川芎嗪拮抗内皮素－1致冠脉收缩效应的初步观察

Effect of Tetramethyl Pyrazine on Coronary Vasoconstrtction Induced by Endothelin-1 in Dogs

用冠脉造影方法观察中药川芎嗪（ＴＭＰ）对内皮素－１（ＥＴ－１）致狗冠脉收缩的拮抗效应。ＥＴ－１５０～１００ｐｍｏｌ冠脉内给药引起冠脉内径减小１７％～２０％（Ｐ＜０．０２），伴有心电图缺血改变。实验组静滴ＴＭＰ８０ｍｇ／ｋｇ后，冠脉内径增加２０％（Ｐ＜０．０３），而且再给相同剂量ＥＴ－１未引起冠脉内径减小，也无心肌缺血发生。可见，ＥＴ１可引起冠脉收缩及心肌缺血，ＴＭＰ能扩张冠脉并拮抗ＥＴ－１的冠脉收缩效应，防止心肌缺血发生。

The purpose of this study was to determine the antagonistic.effect of tetramethyl pyrazine(TMP),a sort of Chinese herbal medicine,on coronary vasoconstriction induced byendothelin-1(ET-1) in closed chest dogs.ET-1 at doses of 50,75 and 100 pmol was selec-tively administered into left main coronary artery and coronary angiogram was performed in1,3 and 10 minutes after intracoronary administration of ET-1.After a 60 minute intervalET-1 administration and coronary angiogram were repeated in two groups in group A with 5dogs intravenous infusion of saline solution was administered while in group B with 4 dogsTMP was infused at a dose of 80mg/kg,Blood pressure of intra-femoral artery , heart rateand ECG were monitored during the experiment.The study demonstrated that coronary ves-sel diameter significantly decreased by 17%(P<0.02) in group A and 20%(P<0.02) ingroup B,associated with ischemia in ECG(4/5 in group A and3/4 in group B)after intra-coronary administration of ET-1.Endothelin-1 induced coronary vasoconstriction and is-chemic changes in ECG were significantly inhibited by intravenous TMP. The coronary di-ameter increased by 20%(P<0.03)after administration of TMP,comparing with the con-trol group.Heart rate had an increased response to TMP. In conclusion this study demon-strated that intracoronary administration of ET-1 caused significant myocardial ischemiathrough coronary vasoconstriction,which was inhibited by TMP.TMP significantly dilatedcoronary artery.