川芎嗪对离体大鼠心室肌缺钙-复钙损伤的防治作用

Study on Preventing-Treating Effect of Tetramethylpyrazine on Calcium Paradox Injury to Isolated Ventricular Muscle of Rats

目的:探讨川芎嗪对心肌细胞在缺钙-复钙损伤中的防治作用及其可能的机制。方法:用细胞内微电极技术记录离体大鼠心室肌细胞“自发”动作电位的方法,观察心室肌细胞在无钙-复钙损伤中快反应电位的幅值(APA)、时程(APD_(50)、APD_(90))、兴奋周期及兴奋节律的变化,以及川芎嗪对该损伤的防治作用。结果:(1)短时间用无钙液灌流的离体大鼠心室肌,在再恢复钙灌流时发生了严重的钙反常损伤(P<0.05)。而在复钙灌流液中加入100μmol/L 川芎嗪时,能显著减轻钙反常损伤(P<0.05)。(2)川芎嗪在高钙液灌流的背景下,抗钙反常损伤的作用减弱。结论:钙拮抗作用是川芎嗪抗缺钙-复钙损伤的可能机制。

Objective:To explore the preventing and treating effect of tetramethylpyrazine (TMP) on myocardial calcium paradox injury and its mechanisms.Methods:Intracellular microelectrode was used to record the spontaneous electric activity in isolated ventricular muscles of rats.The changes of fast response action potential amplitude (APA),the action potential duration (APD_(50),APD_(90)).The excitation period and the excitatory rhythm in isolated ventricular muscle cells,and the preventing-treating effects of TMP on calcium paradox in- jury were observed.Results:(1) 20 min of Ca-free Tyrode buffer was used,but there showed severe injury of the cardiac muscle cells when reperfused with Tyrode buffer with calcium (P<0.05).The reperfusion with Ca-rich Tyrode buffer containing 100 μmol/L of TMP significantly alleviated the Ca paradox-induced myocardial injury (P<0.05).(2) During the reperfusion with high concentration of Ca^(2+) Tyrode buffer containing 100 μmol/L of TMP,the preventing-treating effect of TMP on calcium paradox injury was sup- pressed.Conclusion.The mechanism of TMP in alleviating calcium paradox injury in isolated ventricular muscles of rats possibly was correlated to calcium antagonism.