【摘要】 本文观察了在儿茶酚胺耗竭及 M 受体阻断剂阿托品存在情况下,N₁受体激动剂烟碱（0.6～1.0mmol/L）对组胺及 Bay K8644诱发的豚鼠乳头状肌慢反应电位（SAP）及收缩力（FC）的影响。结果发现,烟碱对 SAP 的动作电位幅值（APA）、最大除极速率（Vmax）、动作电位时程（APD）及 FC 均呈剂量依赖性抑制作用,提示烟碱可能抑制心肌细胞的慢内向电流。更多还原

【Abstract】 The effects of N-receptor agonist Nicotine(0. 6～1. 0 mmol/L)on the slow action potentials(SAP)and the force of contraction(FC),induced by histamine and Bay K8644,wrer ob- served in catecholamine-depleted guinea pig papillary muscles in the presence of an M-cholinergic re ceptor antagonist atropine(3μmol/L).In these preparations mentioned above,nicotine suppressed,in dose-dependent manner,the action potential amplitude(APA),the maximum up stroke velocity(V max),the action potential duration(APD)and FC.These results suggested that the nicotine inhibits the slow inward current lsi of myocardiac cells.更多还原