Protein phosphorylation is required for diazoxide to open ATP‐sensitive potassium channels in insulin (RINm5F) secreting cells

FEBS Letters

Dunne, M.J.¹ 

[1] MRC Secretory Control Research Group, The Department of Physiology, The University of Liverpool, Liverpool L69 3BX, England

关键词: Patch clamp;    K+ channel;    Diazoxide;    ATP;    (RINm5F cell);    ATP;    adenosine 5′-triphosphate;    AMP-PNP;    adenylyl-imidodiphosphate;    AMP-PCP;    methyleneadenosine 5′-triphosphate;    ATPγS;    adenosine 5′-O-(3-thiotriphosphate);   

DOI  :  10.1016/0014-5793(89)80734-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The patch-clamp open-cell recording configuration has been used to investigate the effects of non-hydrolyzable analogues of ATP on the diazoxide-activation of K_ATP channels in the insulin-secreting cell line RINm5F. K⁺ channels inhibited by 0.1, 0.5 and 1.0 mM ATP were consistently activated by 200 μM diazoxide. During sustained activation of channels, exchange of ATP for either AMP-PNP, AMP-PCP or ATPγS abolished the effects of diazoxide. If diazoxide was added to the membrane in the continued presence of AMP-PNP, AMP-PCP or ATPγS either no effects were observed or alternatively a small transient activation of channels occurred. This study suggests that protein phosphorylation is necessary for diazoxide to activate ATP-sensitive potassium channels in insulin-secreting cells.

【 授权许可】

Unknown