Hori M, Shimizu K, Nakajyo S, Urakawa N
Department of Veterinary Pharmacology, Nippon Veterinary and Zootechnical College, Tokyo, Japan.
Eur J Pharmacol. 1989 Jun 8;165(1):63-70. doi: 10.1016/0014-2999(89)90770-x.
The tonic contractions induced in the guinea-pig ileal longitudinal muscle by 60 mM KCl, carbachol, histamine or A23187 were inhibited similarly by Li+-substituted solution. There was a good correlation between the Li+-induced inhibition of contractions induced by these stimulants and the intracellularly accumulated Li+ content. In the experiment with fura-2, Li+-substituted solution inhibited the high-K+-induced contraction without decreasing the cytosolic Ca2+ level elevated by high-K+ solution. The concentration-response curve for Ca2+ in the skinned fiber was shifted to the right by pretreatment with Li+-substituted solution. These results suggest that the inhibitory mechanism of Li+ on the contractions by various stimulants partly involves the direct inhibition of the contractile proteins in the guinea-pig ileal longitudinal muscle.
60 mM氯化钾、卡巴胆碱、组胺或A23187在豚鼠回肠纵肌中诱导产生的强直性收缩，被锂离子替代溶液以类似方式抑制。锂离子对这些刺激物诱导的收缩的抑制作用与细胞内积累的锂离子含量之间存在良好的相关性。在用fura-2进行的实验中，锂离子替代溶液抑制了高钾诱导的收缩，而不降低高钾溶液升高的胞质钙离子水平。用锂离子替代溶液预处理后，去表皮纤维中钙离子的浓度-反应曲线向右移动。这些结果表明，锂离子对各种刺激物引起的收缩的抑制机制部分涉及对豚鼠回肠纵肌中收缩蛋白的直接抑制。
