川芎嗪加强豚鼠乳头状肌慢内向电流的作用  

ENHANCEMENT EFFECT OF TETRAMETHYLPYRAZINE ON SLOW INWARD CURRENT IN GUINEA PIG PAPILLARY MUSCLES

作　　者：白琴[1] 汤树本[1] 

机构地区：[1]河南医科大学生理教研室

出　　处：《生理学报》1994年第5期500-504,共5页Acta Physiologica Sinica

基　　金：国家自然科学基金

摘　　要：川芎嗪剂量依赖性地增加正常豚鼠乳头状肌收缩力（ＦＣ），延长快反应动作电位时程（ＡＰＤ）。川芎嗪使氯化钡或组织胺诱发的慢反应电位（ＳＡＰ）的动作电位幅值（ＡＰＡ），ＡＰＤ，最大除极速率（Ｖｍａｘ）及ＦＣ呈剂量依赖性增加。３．０ｍｍｏｌ／Ｌ的川芎嗪可直接诱发高钾除极化，钠通道失活的豚鼠乳头状肌的ＳＡＰ和收缩，加入１μｍｏｌ／Ｌ维拉帕米后１０ｍｉｎ内，ＳＡＰ及收缩逐步消失。但川芎嗪不能在儿茶酚胺耗竭或普萘洛尔阻断β受体的乳头状肌上诱发ＳＡＰ及收缩。以上结果提示川芎嗪加强慢内向电流的作用可能是通过心肌内儿茶酚胺释放所介导的。Tetramethylpyrazine (TMP) could potentiate the force of contraction and increase the action potential duration (APD) of isolated guinea pig papillary muscles in a dosedependent manner. Similar effects were also observable in BaCl2 or histamine-induced contraction and the accompanied slow action potential (SAP). In fact, contraction and SAP could also be induced by TMP itself at 3. 0 mmol/L concentration and antagonized by verapamil (1μmol/L) within 10 min. In the presence of propranolol or in experiments carried out in catecholamine-depleted (reserpine 2. 5 mg/kg, i. p. 15 h prior to the experiment) muscles, TMP was unable to induce SAP and contraction. These results suggested that the effects of TMP on enhancing Isi were mediated by the release of catecholamine in myocardium.

关 键 词：川芎嗪 乳头状肌 动作电位 

分 类 号：R285.5[医药卫生—中药学]