KATP channels are a newly defined class of potassium channels based on the physical association of an ABC protein, the sulfonylurea receptor, and a K+ inward rectifier subunit. The beta-cell KATP channel is composed of SUR1, the high-affinity sulfonylurea receptor with multiple TMDs and two NBFs, and KIR6.2, a weak inward rectifier, in a 1:1 stoichiometry. The pore of the channel is formed by K...

Iron importer divalent metal transporter 1 (DMT1) plays a crucial role in the nigal iron accumulation in Parkinson's disease (PD). Membrane hyperpolarization is one of the factors that could affect its iron transport function. Besides iron, selective activation of the ATP-sensitive potassium (KATP) channels also contributes to the vulnerability of dopaminergic neurons in PD. Interestingly, acti...

The mechanism by which ATP-sensitive K+ (KATP) channels open in the presence of inhibitory concentrations of ATP remains unknown. Herein, using a four-state kinetic model, we found that the nucleotide diphosphate UDP directed cardiac KATP channels to operate within intraburst transitions. These transitions are not targeted by ATP, nor the structurally unrelated sulfonylurea glyburide, which inh...

BACKGROUND Volatile anesthetics produce differing degrees of myocardial protection in animal models of ischemia. The purpose of the current investigation was to determine the influence of isoflurane and halothane on myocardial protection in a human model of simulated ischemia and the role of adenosine A1 receptors and adenosine triphosphate-sensitive potassium (KATP) channels in the anesthetic ...

ATP-sensitive K channels (KATP channels) play an important role in glucose homeostasis. A single nucleotide polymorphism (SNP) in the Kir6.2 subunit causes a point mutation of Glu23 to lysine and reduces the ATP sensitivity of pancreatic KATP channels. The SNP found in 58% of Caucasians accounts for 15% of type 2 diabetes. Here we show evidence for dysregulations of muscular KATP channels with ...

ATP-sensitive potassium (KATP) channels were first discovered in the heart 30 years ago. Reconstitution of KATP channel activity by coexpression of members of the pore-forming inward rectifier gene family (Kir6.1, KCNJ8, and Kir6.2 KCNJ11) with sulfonylurea receptors (SUR1, ABCC8, and SUR2, ABCC9) of the ABCC protein subfamily has led to the elucidation of many details of channel gating and por...

objective(s):this study aimed to examine the hypothesis that an antiarrhythmic effect might be obtained by ischemic preconditioning of the liver, and also to characterize the potential underlying mechanisms. materials and methods: male wistar rats were anesthetized by thiopental sodium (50 mg/kg, ip) followed by iv injection of heparin (250 iu). remote ischemic preconditioning (ripc) was induce...

THE DISCOVERY AND CHARACTERIZATION OF preconditioning (PC) in the late 1980s has proven to be the most important advancement in the pursuit to identify viable strategies to limit infarct size following myocardial ischemia-reperfusion injury. Ischemic PC (IPC) is a unique, paradoxical phenomenon whereby one or several short intermittent periods of ischemia protects tissue against the injury caus...

Objective: To assess the significance of protein kinase A (PKA) in glucose triggering of ATP-sensitive Kþ (KATP) channel-dependent insulin secretion and in glucose amplification of K þ ATP channel-independent insulin secretion. Methods: Insulin release from cultured perifused mouse pancreatic islets was determined by radioimmunoassay. Results: In islets cultured at 5.5 mmol/l glucose, and then ...

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...