Veselovskiĭ N S, Fedulova S A
Neirofiziologiia. 1986;18(3):313-8.
The effect of replacement of Ca2+ ions by Ba2+ ions in the external artificial solution on a high-threshold calcium current of the somatic membrane of rat dorsal root ganglion neurons was studied by intracellular dialysis technique and voltage clamp method. The conductance of the corresponding channels for Ba2+ ions assessed by the increase in the maximal current amplitude was shown to increase about twice. The decrease of the maximal current amplitude in the course of dialysis associated with the washout of the intracellular content slowed down considerably, probably, due to the removal of the blocking effect of intracellular Ca2+ on the calcium channels. The link of high-threshold calcium channels with cyclic nucleotide metabolism was not disturbed after the replacement of Ca2+ by Ba2+. The data obtained are discussed within the framework of existing ideas about the functioning of calcium channels in excitable membranes.
采用细胞内透析技术和电压钳法，研究了在外部人工溶液中用Ba2+离子替代Ca2+离子对大鼠背根神经节神经元体膜高阈值钙电流的影响。通过最大电流幅度的增加评估的Ba2+离子相应通道的电导增加了约两倍。透析过程中最大电流幅度的降低与细胞内物质的洗脱有关，这一过程可能由于细胞内Ca2+对钙通道的阻断作用的消除而大大减慢。用Ba2+替代Ca2+后，高阈值钙通道与环核苷酸代谢的联系未受干扰。在关于可兴奋膜中钙通道功能的现有观点框架内对所获得的数据进行了讨论。
