体外长期锂处理对青蛙抽动肌纤维钙瞬变的影响及其被外源性肌醇逆转的情况。

Effect of prolonged in vitro lithium treatment on calcium transients in frog twitch muscle fibres and its reversal by exogenous myo-inositol.

作者信息

Zhu P H, Fu D X

机构信息

Department of Cellular and Molecular Neurobiology, Shanghai Institute of Physiology, Chinese Academy of Sciences.

出版信息

Neuroscience. 1990;39(1):271-8. doi: 10.1016/0306-4522(90)90240-5.

DOI:10.1016/0306-4522(90)90240-5

PMID:2089280

Abstract

Using arsenazo III as an intracellular indicator to monitor the calcium transients elicited by voltage-clamp depolarizing pulse, the effect of prolonged in vitro lithium treatment on excitation--contraction coupling in frog twitch muscle fibres was investigated. Incubation in 10 mM Li+ Ringer's solution for 2 days caused a 46% increase in the amplitude of the calcium transients, while treatment with 30 mM Li+ for 2 days produced a depression of 44%. Shortening the bathing time to 1 day, the decrease of calcium transients caused by 30 mM Li+ was reversed to a small increase. For the 2-day incubation, both the increase in the amplitude with 10 mM and the decrease with 30 mM Li+ were abolished by the presence of 1 mM myo-inositol in the bathing medium. These results imply that the turnover of inositol phospholipids is involved in regulating excitation-contraction coupling in skeletal muscle fibres.

摘要

以偶氮胂III作为细胞内指示剂来监测电压钳去极化脉冲引发的钙瞬变，研究了体外长时间锂处理对青蛙单收缩肌纤维兴奋 - 收缩偶联的影响。在含10 mM Li⁺的林格氏溶液中孵育2天，导致钙瞬变幅度增加46%，而用30 mM Li⁺处理2天则产生44%的降低。将孵育时间缩短至1天，30 mM Li⁺引起的钙瞬变减少转变为小幅增加。对于2天的孵育，在孵育介质中存在1 mM肌醇时，10 mM Li⁺引起的幅度增加和30 mM Li⁺引起的降低均被消除。这些结果表明，肌醇磷脂的周转参与调节骨骼肌纤维中的兴奋 - 收缩偶联。