OBJECTIVES We investigated the effects of ischemic preconditioning (PC) on diabetic and failing human myocardium and the role of mitochondrial KATP channels on the response in these diseased tissues. BACKGROUND There is conflicting evidence to suggest that PC is a healthy heart phenomenon. METHODS Right atrial appendages were obtained from seven different groups of patients: nondiabetics, d...

Duncker, D. J., H. H. Oei, F. Hu, R. Stubenitsky, and P. D. Verdouw. Role of KATP 1 channels in regulation of systemic, pulmonary, and coronary vasomotor tone in exercising swine. Am J Physiol Heart Circ Physiol 280: H22–H33, 2001.—The role of ATP-sensitive K (KATP 1 ) channels in vasomotor tone regulation during metabolic stimulation is incompletely understood. Consequently, we studied the con...

In the vasculature, ATP-sensitive potassium channels (KATP) channels regulate vascular tone. Mice with targeted gene disruptions of KATP subunits expressed in vascular smooth muscle develop spontaneous coronary vascular spasm and sudden death. From these models, it was hypothesized that the loss of KATP channel activity in arterial vascular smooth muscle was responsible for coronary artery spas...

Although ATP-sensitive K+ (KATP) channel openers depress force, channel blockers have no effect. Furthermore, the effects of channel openers on single action potentials are quite small. These facts raise questions as to whether 1) channel openers reduce force via an activation of KATP channels or via some nonspecific effects and 2) the reduction in force by KATP channels operates by changes in ...

The ATP-sensitive potassium (KATP) channel in pancreatic islet beta cells consists of four pore-forming (Kir6.2) subunits and four regulatory sulfonylurea receptor (SUR1) subunits. In beta cells, the KATP channel links intracellular metabolism to the dynamic regulation of the cell membrane potential that triggers insulin secretion. Syntaxin 1A (Syn-1A) is a SNARE protein that not only plays a d...

ATP-modulated K+ channels play an important role in regulating membrane excitability during metabolic stress. To characterize such K+ channels from the human brain, single channel currents were studied in excised inside-out patches from freshly dissociated human neocortical neurons. Three currents that were sensitive to physiological concentrations of ATP and selectively permeable to K+ were id...

1. ATP-sensitive potassium (KATP) channels are composed of pore-forming (Kir6.x) and regulatory sulphonylurea receptor (SURx) subunits. We have isolated a novel SUR variant (SUR1bDelta33) from a hypothalamic cDNA library. This variant lacked exon 33 and introduced a frameshift that produced a truncated protein lacking the second nucleotide binding domain (NBD2). It was expressed at low levels i...