【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。更多还原

【Abstract】 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.更多还原