Because we were interested in assessing glucose-mediated regulation of the activity of sarcolemmal ATP-sensitive K(+) channels (K(ATP) channels) (which are closed by physiological levels of intracellular ATP and serve to couple intracellular metabolism with the membrane excitability in the heart) during ischemia, we performed experiments designed to test whether high extracellular glucose would...

The type of metabolic compartmentalization that occurs in red blood cells differs from the types that exist in most eukaryotic cells, such as intracellular organelles. In red blood cells (ghosts), ATP is sequestered within the cytoskeletal-membrane complex. These pools of ATP are known to directly fuel both the Na(+)/K(+) and Ca(2+) pumps. ATP can be entrapped within these pools either by incub...

Sulfonylurea receptor-containing ATP-sensitive potassium (K(ATP)) channels have been implicated in cardioprotection, but the cell type and constitution of channels responsible for this protection have not been clear. Mice deleted for the first nucleotide binding region of sulfonylurea receptor 2 (SUR2) are referred to as SUR2 null since they lack full-length SUR2 and glibenclamide-responsive K(...

ATP modulates various functions in the dental pulp cells, such as intercellular communication and neurotransmission between odontoblasts and neurons, proliferation of dental pulp cells, and odontoblast differentiation. However, functional expression patterns and their biophysical properties of ionotropic ATP (P2X) receptors (P2X1-P2X7) in odontoblasts were still unclear. We examined these prope...

BACKGROUND AND PURPOSE The structurally related, inwardly rectifying K+ (K(IR)) channel and the ATP-sensitive K+ (K(ATP)) channel are important modulators of cerebral artery tone. Although protein kinase C (PKC) activators have been shown to inhibit these channels with the use of patch-clamp electrophysiology, effects of PKC on K+ channel function in intact cerebral blood vessels are unknown. W...

The effects of ATP-analogues on Ca2+-ATPase and (Na++ K+)-ATPase have been studied. The participation of sulfhydryl groups in the recognition of ATP by both transport ATPases is indicated by the fact, that the disulfide of thioinosine triphosphate inactivates both enzymes. The reactivity of rapidly and slowly reacting sulfhydryl groups in the ATP binding sites of both enzymes is altered by the ...

Recent evidence suggests that both adenosine receptor (AR) and K ATP channel activation exert antihypertrophic effects in cardiac myocytes. We studied the relative contributions of mitochondrial K ATP (mitoK ATP) and sarcolemmal K ATP (sarcK ATP) to the antihypertrophic effects of ARs in primary cultures of neonatal rat ventricular myocytes exposed for 24 h with the alpha1 adrenoceptor agonist ...

An ATP-hydrolyzing activity with the properties of a Mg(2+)-dependent (Na(+),K(+))-ATPase (ATP phosphohydrolase, EC 3.6.1.3) from a 20-fold purified plasma membrane fraction of the marine diatom, Nitzschia alba is described. The basal activity requires Mg(2+) and further stimulation by Na(+) or Na(+) plus K(+) is dependent on the presence of Mg(2+); Mn(2+) or Co(2+) can partially substitute for...