PURPOSE Cultured rabbit nonpigmented ciliary epithelium (NPE) transports ascorbic acid (ASC) inward through a sodium-dependent mechanism. This study was conducted to test whether Na-K transport is activated to export the additional sodium, which enters the cell in cotransport with ASC. METHODS Studies were conducted using a cell line derived from rabbit NPE. ASC uptake was measured using [14C...

I N RECENT years clearance techniques have been developed which permit precise measurements of the rates at which some substances are transported from tubular lumen to peritubular capillaries (glucose, amino acids, ascorbic acid, etc.) and others from peritubular fluid to the lumina of the tubules (p-aminohippurate, diodrast, phenol red, etc.). Many of the tubular excretory and reabsorptive pro...

BACKGROUND Statins (3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors) consumption provides beneficial effects on cardiovascular systems. However, effects of statins on vascular KATP channel gatings are unknown. METHODS Pig left anterior descending coronary artery and human left internal mammary artery were isolated and endothelium-denuded for tension measurements and West...

The low rate of endogenous respiration exhibited by the blue-green algae Anacystis nidulans and Phormidium luridum was not increased by the addition of respiratory substrates. However, endogenous respiration was inhibited by low concentrations of cyanide and by high carbon monoxide tensions. In addition, the uncouplers dinitrophenol and carbonyl cyanide p-trifluoromethoxyphenylhydrazone both st...

Measurements of the stereospecific uptake of micromolar concentrations of n-glucose by rabbit renal brush border preparations suggested saturation at a “high afanity site” only when incubations at 20” were prolonged, but not when the incubation period was 34 min. This prompted a renewed effort to ascertain whether the apparent saturability at the longer incubation periods was due to bacterial c...

ONE ofthe grounds on which disturbance of glycolysis has been assumed to be responsible for experimentally induced degeneration of the retina is the observation recorded by Noell (1951) that injection of sodium iodoacetate abolishes the electric response of the retina much more markedly in mammals than in other species. This finding is suggestive in view of the fact that the mammalian retina is...

This study investigated the regulation of glucose uptake in Atlantic cod (Gadus morhua) hearts. Isolated hearts were perfused with or without glucose in the medium, under either normoxic or severely hypoxic conditions. Working at basal levels, hearts did not require extracellular glucose to maintain power under aerobic conditions. However, cardiac performance was significantly reduced without e...

Strategies to amplify whole-body glucose disposal are key therapies to treat type 2 diabetes. Mice that over-express glucose transporter 4 (Glut4) in skeletal muscle, heart, and adipose tissue (G4Tg) exhibit increased fasting glucose disposal and thus lowered blood glucose. Intriguingly, G4Tg mice also exhibit improved insulin-stimulated suppression of endogenous glucose production even though ...

Monolayers of the porcine-derived renal epithelial cell line, LLC-PK1, were used to characterize the effects of heat stress on Na+-glucose cotransport. Transepithelial current dependent on 5 mM glucose ( I Glc), phloridzin-sensitive current ( I phz), and total transepithelial current ( I total) were measured as indicators of Na+-glucose cotransport. Severe heat shock (SHS; 45°C for 1 h, then 37...

OBJECTIVE β-Cell and islet endothelial cell destruction occurs during the progression of type 1 diabetes, but, paradoxically, β-cell proliferation is increased during this period. Altered glucose tolerance may affect β-cell mass and its association with endothelial cells. Our objective was to study the effects of glucose and inflammation on islet vascularity and on β function, mass, and insulin...