钡、锌和镉离子对离体蜗牛食道下神经节细胞放电的影响

本文应用了细胞内微电极电位记录技术和放射性同位素示踪方法研究了与钙通道具有不同关系的Ba~(2 )、Zn~(2 )和Ca~(2 )三种二价阳离子对爆放性放电的效应,并对其机理作了初步讨论.20mMBaCl_2或17mM ZnSO_4均可使具有自发放电的神经细胞产生爆放性放电.Ba~(2 )和Zn~(2 )引起的爆放性放电,在振幅、持续时间、去极化波振幅和峰电位数等参数上都具有统计学意义上的高度显著性差异.10mM CdCl_2对自发动作电位在振幅和频率上均显示抑制效应.~(45)Ca同位素示踪实验结果表明,在Ba~(2 )、Zn~(2 )和Cd~(2 )的分别作用下,~(45)Ca进入胞内量都是减少的.

THE INFLUENCE OF Ba~(2+),Zn~(2+) AND Cd~(2+) IN ISOLATED GANGLION CELLS OF AFRICAN SNAIL ON DISCHARGES

A intracellular microelectrode recording technique and radioisotope tracer method were used to study the effect of Ba2+,Zn2+,and Cd2+ which have different relations with calicium channel, on burst discharges(BD) ,and their mechanisms were explorated preliminarily. BD were evoked by 20mM BaCl2 or 17 mM ZnSO4 in the neurons with spontaneous discharges.These effects are reversible. The parameters of BD evoked by Ba2+ and Zn2+, for example, amplitude and duration of BD, amplitude of slow depolarization and numbers of spike have statistically significant differences. 10mM CdCl2 has inhibitory effect on action potential in amplitude and frequency. The results obtained by 45Ca tracer experiments indicate that45Ca]i; are decreased under actions of Ba2+, Zn2+ or Cd2+ respectively.