Cs对兔窦房结细胞起搏离子流I_f和I_K及自律活动的影响  

EFFECTS OF Cs ON ATUOMATICTTY AND PACEMAKER CURRENT I_f AND I_K IN RABBIT SINUS NODE CELLS

作　　者：李慈珍[1] 刘远谋[1] 杨智昉[1] 陆红丽[1] 

机构地区：[1]上海第二医科大学生理教研室,上海200025

出　　处：《生理学报》1998年第4期409-415,共7页Acta Physiologica Sinica

基　　金：国家自然科学主任基金!39740005;上海第二医科大学科学基金

摘　　要：运用微电极记录窦房结细胞动作电位及穿孔膜片箝技术（perforstedpatch）记录酶解游离的窦房结细胞电流，研究兔心窦房结的起搏原理。实验结果显示，Cs对自律性动作电位的频率及4期自动除极速率仅有轻度抑制作用。在同一细胞、同一时间、同一测试电位范围内，Cs能基本阻断If及它的电导变化而对Ik电流无明显抑制作用。上述结果表明在兔心窦房结细胞的起搏活动初期，If不是起搏的主要因素。Conventional microelectrode and perforated patch clamp techniques were employed to study the pacemaker mechanisms in enzyme-isolated font sinus node cells. 2 mmol/LCs had little effect on automatic discharge of the SA node and the slope Of diastolic depolarization. Cs blocked both If and slope conductance increase but left Ik largely unaffected. The results suggest that if is not essential for the first stage of automatic activity of the rabbit SA node.

关 键 词：窦房结 膜片箝 起搏离子流 动作电位 

分 类 号：Q463[生物学—生理学]