Zhang, Hong Yan, Bradley C McPherson, Huiping Liu, Timir S Baman, Peter Rock, and Zhenhai Yao. H2O2 opens mitochondrial KATP channels and inhibits GABA receptors via protein kinase Cin cardiomyocytes. Am J Physiol Heart Circ Physiol 282: H1395–H1403, 2002; 10.1152/ajpheart.00683.2001.—Oxygen radicals and protein kinase C (PKC) mediate ischemic preconditioning. Using a cultured chick embryonic c...

Pancreatic beta-cells secrete insulin in response to closure of ATP-sensitive K+ (KATP) channels, which causes membrane depolarization and a concomitant rise in intracellular Ca2+ (Cai). In intact islets, beta-cells are coupled by gap junctions, which are proposed to synchronize electrical activity and Cai oscillations after exposure to stimulatory glucose (>7 mM). To determine the significance...

OBJECTIVES The possible role of the ATP-sensitive potassium (KATP) channel in cardioprotection by Na+-H+ exchange (NHE) inhibition was examined. BACKGROUND The KATP channel is suggested to be involved not only in ischemic preconditioning but also in some pharmacological cardioprotection. METHODS Infarction was induced by 30-min coronary occlusion in rabbit hearts in situ or by 30-min global...

Introduction: Uncoupling protein 2 (UCP2) in the inner mitochondrial membrane changes the activity of KATP channels and the cell excitability, probably by decreasing the ATP production. Given the expression of UCP2 in primary afferent neurons, and the importance of these channels in morphine-induced analgesia, genipin, an UCP2 inhibitor, may affect these processes, when administrated intratheca...

Hypoxia-induced shortening of cardiac action potential duration (APD) has been attributed in mammalian hearts to the activation of ATP-sensitive potassium (KATP) channels. Since KATP channels are also present at high densities in the hearts of vertebrate ectotherms, speculation arises as to their function during periods of reduced environmental oxygen. The purpose of the present study was to de...

Cardiomyopathies have been indicated to be one of the leading causes of heart failure. Though it was indicated that genetic defects, viral infection and trace element deficiency were among the causes of cardiomyopathy, the etiology has remained to be fully elucidated. Cardiomyocytes require large amounts of energy to maintain their normal biological functions. Adenosine triphosphate-sensitive p...

NICHOLS, C. G., AND W. J. LEDERER. Adenosine triphosphate-sensitive potassium channels in the cardiovascular system. Am. J. Physiol. 261 (Heart Circ. Physiol. 30): H1675-H1686, 1991.-ATP is normally available in cells at millimolar concentrations and is “buffered” by intracellular pools of other high-energy phosphates, such as creatine phosphate. Thus intracellular [ATP] ([ATPI;) may seem an un...

Sulfonylurea derivatives glibenclamide and tolbutamide are selective blockers of ATP-sensitive K+ (KATP) channels. However, their ability to prevent cellular K+ loss and shortening of action potential duration during ischemia or hypoxia in the intact heart is modest compared with their efficacy at blocking KATP channels in excised membrane patches. In the isolated arterially perfused rabbit int...