膜片钳法研究钡离子对SV通道电流特性的影响Effects of Ba2+ on SV Currents Character by Patch-clamp
张丽平,钱天伟,杨国义,杨频
摘要(Abstract):
利用全液泡膜片钳技术,研究了氯化钡对慢液泡阳离子通道电流特性的影响.外液中加入氯化钡后,在低浓度时,促进通道电流,且促进效率随着浓度的增大而增大,并随刺激电压而变化;而在高浓度时,则抑制通道电流,抑制率随刺激电压的增大先增大而后又有所减小。同时加入氯化钡后,通道的激活时间常数明显减小,激活电压在20mV-120mV时,减小的比较明显,而大于120mV时,则不太明显。这些提示SV通道上可能存在着钡离子的结合位点,而且此结合位点结合钡离子以后,可以加快通道的开放几率。
关键词(KeyWords): 膜片钳技术;SV通道;液泡;钡离子
基金项目(Foundation): 山西省青年科学基金项目(2007021010)
作者(Author): 张丽平,钱天伟,杨国义,杨频
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