Cardiac mitochondrial ATP-sensitive potassium channel is activated by nitric oxide in vitro.
Previous observations on the activation of the mitochondrial ATP-sensitive potassium channel (mitoK(ATP)) by nitric oxide (NO) in myocardial preconditioning were based on indirect evidence. In this study, we have investigated the direct effect of NO on the rat cardiac mitoK(ATP) after reconstitution of the inner mitochondrial membranes into lipid bilayers. We found that the mitoK(ATP) was activated by exogenous NO donor S-nitroso-N-acetyl penicillamine or PAPA NONOate. This activation was inhibited by mitoK(ATP) blockers 5-hydroxydecanoate or glibenclamide. Our observations confirm that NO can directly activate the cardiac mitoK(ATP), which may underlie its contribution to myocardial preconditioning.
Ljubkovic
Marko
M
Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
Shi
Yang
Y
Cheng
Qunli
Q
Bosnjak
Zeljko
Z
Jiang
Ming Tao
MT
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D006834:Hydrazines / Q000494:pharmacology; D015640:Ion Channel Gating / Q000187:drug effects*; D008051:Lipid Bilayers / Q000378:metabolism; D008297:Male; D008929:Mitochondria, Heart / Q000187:drug effects* / Q000378:metabolism*; D009569:Nitric Oxide / Q000494:pharmacology*; D015221:Potassium Channels / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D026423:S-Nitroso-N-Acetylpenicillamine / Q000494:pharmacology
D006834:Hydrazines; D008051:Lipid Bilayers; C112653:PAPA NONOate; D015221:Potassium Channels; C117780:mitochondrial K(ATP) channel; D009569:Nitric Oxide; D026423:S-Nitroso-N-Acetylpenicillamine; D000255:Adenosine Triphosphate