Apoptosis plays an important role in maintaining the balance between proliferation and cell loss in the intestinal epithelium. Apoptosis rates may increase in intestinal pathologies such as inflammatory bowel disease and necrotizing enterocolitis, suggesting pharmacological prevention of apoptosis as a therapy for these conditions. Here, we explore the feasibility of this approach using the rat...

Macrophages express a number of proteins involved in sterol efflux pathways, including apolipoprotein E (apoE) and scavenger receptor class B type I (SR-BI). We have investigated a potential interaction between these two sterol efflux pathways in modulating overall macrophage sterol flux. We utilized an experimental system in which we increased expression of each of these proteins to a high phy...

"Low sodium" muscles were prepared which contained around 5 mmoles/kg fiber of intracellular sodium. "High sodium" muscles containing between 15 and 30 mmoles/kg fiber of intracellular sodium were also prepared. In low sodium muscles application of 10(-5)M strophanthidin reduced potassium influx by about 5%. Potassium efflux was unaffected by strophanthidin under these conditions. In high sodiu...

Recent studies demonstrate that HDL's ability to promote cholesterol efflux from macrophages associates strongly with cardioprotection in humans independently of HDL-cholesterol (HDL-C) and apoA-I, HDL's major protein. However, the mechanisms that impair cholesterol efflux capacity during vascular disease are unclear. Inflammation, a well-established risk factor for cardiovascular disease, has ...

Erythrocyte sodium efflux as well as sodium, potassium, and water content were studied in 12 untreated men with uncomplicated essential hypertension and in 18 normotensive control subjects. In the patients with essential hypertension, the rate constant for total sodium efflux was significantly lower than in the normotensives (5.96.10(-3) +/- 0.45.10(-3) min-1 vs 6.69.10(-3) +/- 0.49.10(-3) min-...

OBJECTIVES Infusion of reconstituted HDL (rHDL) leads to changes in HDL metabolism as well as to an increased capacity of plasma to support cholesterol efflux providing an opportunity to investigate mechanisms linking cholesterol efflux to changes in plasma HDL. METHODS AND RESULTS Patient plasmas after infusion of rHDL were tested ex vivo for their capacity to stimulate cholesterol efflux. R...

The magnitude of the activating effect of ATP on the Ca efflux was explored at different [Ca++]i in squid axons previously exposed to cyanide seawater and internally dialyzed with a medium free of ATP and containing p-trifluoro methoxy carbonyl cyanide phenyl hydrazine. At the lowest [Ca++]i used (0.06 micron more than 95% of the Ca efflux depends on ATP. At high [Ca++]i (100 micron), 50-60% of...

RATIONALE High-density lipoprotein (HDL) is a heterogeneous population of particles. Differences in the capacities of HDL subfractions to remove cellular cholesterol may explain variable correlations between HDL-cholesterol and cardiovascular risk and inform future targets for HDL-related therapies. The ATP binding cassette transporter A1 (ABCA1) facilitates cholesterol efflux to lipid-free apo...

Intercellular transport of auxin is mediated by influx and efflux carriers in the plasma membrane and subjected to developmental and environmental regulation. Here, using the auxin-sensitive Arabidopsis thaliana root hair cell system and the tobacco (Nicotiana tabacum) suspension cell system, we demonstrate that the protein kinase PINOID (PID) positively regulates auxin efflux. Overexpression o...

OBJECTIVES Acinetobacter baumannii has emerged as an important nosocomial pathogen in hospitalized patients, and causes a multitude of infections with significant morbidity and mortality. The aim of this study was to elucidate the role of a novel efflux pump in A. baumannii. METHODS The open reading frame ABAYE1518, annotated as a putative Methyl Viologen resistance protein in the genome of s...