Potassium channels play an important role in the regulation of vascular smooth muscle tone and, thus, contribute to the regulation of blood pressure, blood flow, and microvascular exchange.1 These channels importantly participate in the determination of vascular smooth muscle cell (VSMC) membrane potential,1,2 which, in turn, controls Ca influx through voltage-gated Ca channels1,2 and has been ...

KATP channels were reconstituted in COSm6 cells by coexpression of the sulfonylurea receptor SUR1 and the inward rectifier potassium channel Kir6.2. The role of the two nucleotide binding folds of SUR1 in regulation of KATP channel activity by nucleotides and diazoxide was investigated. Mutations in the linker region and the Walker B motif (Walker, J.E., M.J. Saraste, M.J. Runswick, and N.J. Ga...

Earlier studies have suggested that halothane may relax smooth muscle in part by opening adenosine triphosphate-sensitive potassium (KATP) channels. We tested this hypothesis in vitro by examining the interaction of halothane with glibenclamide, a KATP channel blocker, and YM934, a KATP channel opener, in strips of canine tracheal smooth muscles mounted in an organ bath system. To examine the s...

Functional KATP (ATP-sensitive potassium) channels are hetero-octamers of four Kir6 (inwardly rectifying potassium) channel subunits and four SUR (sulphonylurea receptor) subunits. Possible interactions between the C-terminal domain of SUR2A and Kir6.2 were investigated by co-immunoprecipitation of rat SUR2A C-terminal fragments with full-length Kir6.2 and by analysis of cloned KATP channel fun...

Action potentials, which define electrical excitability, depend on the activity of voltage-gated Na, Ca and K (Kv) channels (see the review in this issue by Sanguinetti and Tristani-Firouzi, p. 463). But electrical activity without modulation would be like an automobile with one speed, no steering and no brakes. In addition to the channels that play the leading parts, bio-electric signalling in...

BACKGROUND AND PURPOSE--Endothelin-1, in concentrations similar to that present in cerebrospinal fluid after fluid percussion brain injury (FPI), increases superoxide anion (O2-) production. Endothelin-1 also contributes to altered cerebral hemodynamics after FPI through impairment of ATP-sensitive K+ (KATP) channel function through protein kinase C (PKC) activation. Generation of O2- additiona...

Huh, Joon, Garrett J. Gross, Hiroshi Nagase, and Bruce T. Liang. Protection of cardiac myocytes via d1-opioid receptors, protein kinase C, and mitochondrial KATP channels. Am J Physiol Heart Circ Physiol 280: H377–H383, 2001.—The objective of the present study was to investigate the role of d1-opioid receptors in mediating cardioprotection in isolated chick cardiac myocytes and to investigate w...

The ATP-dependent potassium (KATP) channel in the pancreatic beta-cell is a complex of two proteins, the pore-forming Kir6.2 and the sulfonylurea receptor type 1 (SUR1). Both subunits are required for functional KATP channels because expression of Kir6.2 alone does not result in measurable currents. However, truncation of the last 26 or 36 amino acids of the C terminus of Kir6.2 enables functio...

ATP-sensitive potassium (KATP) channel openers have a relaxation effect due to the lower cellular membrane potential and inhibit calcium influx. There has been considerable interest in exploring KATP channel openers in the treatment of various diseases such as cardiovascular, cerebrovascular, and urinary system disease and premature labor. The purpose of this study was to synthesize 3,3,6,6-tet...