TRPC1 associates with BKCa channel to form a signal complex
作者单位：Chinese University of Hong Kong
会议名称：《第七届海峡两岸心血管科学研讨会》
会议日期：2009年
学科分类：1001[医学-基础医学(可授医学、理学学位)] 10[医学]
摘 要：TRPC1 is a Ca-permeable cation channel involved in diverse physiological ***1 may associate with other proteins to form a signaling complex,which is crucial for channel *** the present study,we investigated the interaction between TRPC1 and large conductance Ca-sensitive K channel(BKCa).With the use of potentiometric fluorescence dye DiBAC4(3),we found that store-operated Cainflux(SOC)resulted in membrane hyperpolarization of vascular smooth muscle cells(VSMCs).The hyperpolarization was inhibited by an anti-TRPC1 blocking antibody T1E3 and two BKCa channel blockers charybdotoxin and *** data were confirmed by sharp microelectrode measurement of membrane potential in VSMCs of intact ***, T1E3 treatment markedly enhanced the membrane depolarization and contraction of VSMCs in response to several contractile agonists including phenylephrine,endothelin-1,and *** co-immunoprecipitation experiments, an antibody against BKCa alpha-subunit[BKCa-alpha]could pull down TRPC1,and moreover an anti-TRPC1 antibody could reciprocally pull down BKCa(alpha).Double-labeling immunocytochemistry showed that TRPC1 and BKCa were co-localized in the same subcellular regions,mainly on the plasma membrane,in *** data suggest that,TRPC1 physically associates with BKCa in VSMCs,and that Cainflux through TRPC1 activates BKCa to induce membrane *** hyperpolarizing effect of TRPC1-BKCa coupling could serve to reduce agonist-induced membrane depolarization,thereby preventing excessive contraction of VSMCs to contractile ***4 is reported to interact with *** explored the interaction of TRPC1-BKCa with *** results suggest a presence of complex composed of TRPC1-TRPV4-BKCa.