Tauc M, Gastineau M, Poujeol P
Département de Biologie Cellulaire et Moléculaire, CEN Saclay, Gif sur Yvette, France.
Biochem Biophys Res Commun. 1993 Jan 29;190(2):596-601. doi: 10.1006/bbrc.1993.1090.
86Rb+ efflux was measured on polarized Madin-Darby canine kidney cells under A23187 or ATP stimulation. This efflux, inhibited by barium, Leiurus quinquestriatus hebraeus venom and charybdotoxin was attributed to the stimulation of Ca(++)-activated maxi K+ channels. Snake venom from Dendroaspis polylepis did not alter the stimulation as well as did apamine. ATP was effective on both the apical and basolateral membranes and the Ca(++)-activated maxi K+ channels were predominantly found on the basolateral membrane. This study presents the physiological evidence that dendrotoxin is ineffective on the epithelial Ca(++)-activated maxi K+ channel present in MDCK cells.
在A23187或ATP刺激下，对极化的犬肾上皮细胞（Madin-Darby canine kidney cells）进行⁸⁶Rb⁺外流测定。这种外流受到钡、以色列金蝎毒液和蝎毒素的抑制，被认为是由Ca(++)激活的大电导钾通道的刺激所致。黑曼巴蛇毒和蜂毒对这种刺激没有影响。ATP对顶端膜和基底外侧膜均有效，且Ca(++)激活的大电导钾通道主要位于基底外侧膜。本研究提供了生理证据，表明树突毒素对MDCK细胞中存在的上皮Ca(++)激活的大电导钾通道无效。
