[Effect of adenosine triphosphate-dependent potassium channel activators on electrical reactions of intact and cultured endothelial cells].
The influence of pinacidil, an activator of ATP-sensitive K+ channels, on the membrane potential of endothelial cells from intact rat aorta and cultured endothelial cells was investigated. Pinacidil evoked a slowly developing sustained hyperpolarization of endothelial cells from isolated artery with the amplitude of 15 +/- 4 MV from the resting membrane potential of -44 +/- 1 MB. In contrast, in cultured endothelial cells pinacidil was without response. Diazoxide, another activator of ATP-sensitive K+ channels, in half of the cultured cells tested, evoked a slowly developing sustained hyperpolarization with the amplitude of 3 mV. The rest of the cells studied did not respond by membrane potential changes to diazoxide. It was suggested that high sensitivity of the membrane potential of in situ endothelial cells to potassium channels openers may represent a potent signaling mechanism influencing endothelial cell function upon stimulation of vascular KATP channels.
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Bondarenko
D000818:Animals; D002478:Cells, Cultured; D003981:Diazoxide / Q000494:pharmacology*; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D015640:Ion Channel Gating / Q000187:drug effects; D054086:KATP Channels / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects*; D020110:Pinacidil / Q000494:pharmacology*; D051381:Rats
D054086:KATP Channels; D020110:Pinacidil; D003981:Diazoxide