膜片钳法研究钡离子对SV通道电流特性的影响  

Effects of Ba^(2+) on SV Currents Character by Patch-clamp

作　　者：张丽平[1] 钱天伟[1] 杨国义[1] 杨频[2] 

机构地区：[1]太原科技大学环境科学研究所,太原030024 [2]山西大学分子科学研究所化学生物学与分子工程教育部重点实验室,太原030006

出　　处：《太原科技大学学报》2007年第3期247-251,共5页Journal of Taiyuan University of Science and Technology

基　　金：山西省青年科学基金项目(2007021010)

摘　　要：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。Using the whole cell patch-clamp technique, the effect of Ba^2＋ on Slow Vacuolar current＇s characteristic isstudied in Radish tonoplast. The results showed that the addition of Ba^2＋ with a lower concentration to the bath solution significantly promotes the SV currents, and that the promotion ratio increases with increasing Ba^2＋ concentration and changes with different voltage. While at higher concentration, it inhibits SV currents and the percentage of inhibition increases with increasing voltage and then becomes lesser. At the same time, the time constants of activation decreases after the addition of Ba^2＋. The curve is relative sleep between 20mV and 120mV and the slope dramatically decreases at more positive potentials. These results show that there may exist some Ba^2＋ binding sites on SV channels and binding, which improves the open ratio of SV channels.

关 键 词：膜片钳技术 SV通道 液泡 钡离子 

分 类 号：O614.3[理学—无机化学]