利多卡因对离体豚鼠浦肯野纤维的电生理效应：与对乳头肌的效应比较。

Electrophysiological effects of lidocaine on isolated guinea pig Purkinje fibers: comparison with its effects on papillary muscle.

Aomine M

Reingold ECG Center Department of Medicine, Northwestern University Medical School, Chicago, IL 60611.

Gen Pharmacol. 1989;20(1):99-104. doi: 10.1016/0306-3623(89)90069-4.

Abstract

The effects of lidocaine on action potentials of isolated guinea pig Purkinje fibers were examined and compared with those on the papillary muscle, by use of conventional microelectrode techniques. 2. Lidocaine 2.1 x 10(-4) M significantly depressed the resting membrane potential, amplitude, overshoot, maximum upstroke velocity, and duration of action potential of the Purkinje fibers stimulated at cycle length (CL) 1 sec, while the lower concentration (2.1 x 10(-5) M) produced no significant effect. 3. Various parameters of action potentials from the papillary muscle at CL = 1 sec were also depressed by lidocaine 2.1 x 10(-4) M, but the extent of the depression was less marked than in Purkinje fibers. 4. When the Purkinje fibers were stimulated at various CLs (0.3-10 sec), the shortening of action potential duration induced by lidocaine was more evident at slower stimulus rate.

摘要

采用传统微电极技术，研究了利多卡因对豚鼠离体浦肯野纤维动作电位的影响，并与对乳头肌动作电位的影响进行了比较。2. 2.1×10⁻⁴ M的利多卡因显著降低了在周期长度（CL）为1秒时刺激的浦肯野纤维的静息膜电位、幅度、超射、最大上升速度和动作电位持续时间，而较低浓度（2.1×10⁻⁵ M）则无显著影响。3. 2.1×10⁻⁴ M的利多卡因也使CL = 1秒时乳头肌动作电位的各种参数降低，但降低程度不如浦肯野纤维明显。4. 当以不同的CL（0.3 - 10秒）刺激浦肯野纤维时，利多卡因诱导的动作电位持续时间缩短在较慢刺激速率下更明显。