标题:Elevation of intracellular calcium by muscarinic receptor activation induces a block of voltage-activated rat ether-à-go-go channels in a stably transfected cell line
期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1996
卷号:93
期号:18
页码:9910-9914
DOI:10.1073/pnas.93.18.9910
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We have studied the properties of r-eag voltage-activated potassium channels in a stably transfected human embryonic kidney cell line. It was found that r-eag channels are rapidly and reversibly inhibited by a rise in intracellular calcium from 30 to 300 nM. The inhibition does not appear to depend on the activity of calcium-dependent kinases and phosphatases. The effect of calcium on r-eag channel activity was studied in inside-out membrane patches. Calcium inhibited r-eag channel activity with a mean IC50 of 67 nM. Activation of muscarinic receptors, generating calcium oscillations in the transfected cells, induced a synchronous inhibition of r-eag mediated outward currents. This shows that calcium can mediate r-eag current inhibition following muscarinic receptor activation. The data indicate that r-eag channels are calcium-inhibitable voltage-activated potassium channels.