Wang, Lianguo, Gennady Cherednichenko, Lisa Hernandez, Jessica Halow, S. Albert Camacho, Vincent Figueredo, and Saul Schaefer. Preconditioning limits mitochondrial Ca21 during ischemia in rat hearts: role of KATP channels. Am J Physiol Heart Circ Physiol 280: H2321–H2328, 2001.—Prolonged myocardial ischemia results in an increase in intracellular calcium concentration ([Ca]i), which is thought ...

Existing concepts and models for glucose-stimulated insulin secretion (GSIS) are overviewed and a newer perspective has been formulated toward the physiological understanding of GSIS. A conventional model has been created on the basis of in vitro data on application of a square wave high glucose in the absence of any other stimulatory inputs. Glucose elicits rapid insulin release through an ade...

ATP sensitive potassium (KATP) channels are metabolic sensors with channel activity promoted by decreases in ATP andnor increases in MgADP. The most studied are channels present in cardiac myocytes and pancreatic b cells but KATP currents also exist more widely in a range of tissues and organs [1,2]. The channel is a hetero-octamer comprising four sulphonylurea receptors and four pore-forming i...

OBJECTIVES We sought to define effects of glibenclamide, a sulfonylurea known to block ATP-dependent potassium (KATP) channels, and Nomega-nitro-L-arginine methyl ester (L-NAME), an L-arginine analog known to block nitric oxide (NO) synthesis, on coronary vascular responsiveness to adenosine. BACKGROUND The role of adenosine in coronary flow regulation becomes increasingly important when KATP...

We have shown previously that acute ischemia leads to depolarization of pulmonary microvascular endothelial cells that is prevented with cromakalim, suggesting the presence of ATP-sensitive K+ (KATP) channels in these cells. Thus KATP channel expression and activity were evaluated in rat pulmonary microvascular endothelial cells (RPMVEC) by whole cell current measurements, dot blot (mRNA), and ...

Discovered in the cardiac sarcolemma, ATP-sensitive K+(KATP) channels have more recently also been identified within the inner mitochondrial membrane. Yet the consequences of mitochondrial KATP channel activation on mitochondrial function remain partially documented. Therefore, we isolated mitochondria from rat hearts and used K+ channel openers to examine the effect of mitochondrial KATPchanne...

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...

Although it is well established that ischemic preconditioning (IPC) and pharmacological preconditioning (PPC) protect cardiac myocytes against reversible and irreversible injury and the genesis of cardiac arrhythmias1 in all animal species and humans, the effect of IPC and PPC on endothelial dysfunction has been less thoroughly studied. In this regard, the first article to clearly establish tha...

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...

EPAC (Exchange Proteins Activated by cAMP) regulates glutamate transmitter release in the central neurons, but a role underlying this regulation has yet to be identified. Here we show that EPAC binds directly to the intracellular loop of an ATP-sensitive potassium (KATP) channel type-1 sulfonylurea receptor (SUR1) receptor consisting of amino acids 859-881 (SUR1(859-881)). Ablation of EPAC or e...