The purpose of this study was to investigate the factors controlling membrane permeability to potassium of smooth muscle cells from rat aorta stimulated by depolarization. The increase 42K+ efflux (change in the rate constant) induced by depolarization (application of high concentrations of potassium chloride) was inhibited significantly by the calcium antagonists diltiazem and nisoldipine. Par...

The purpose of this study was to investigate the factors controlling membrane permeability to potassium of smooth muscle cells from rat aorta stimulated by depolarization. The increase in K + efflux (change in the rate constant) induced by depolarization (application of high concentrations of potassium chloride) was inhibited significantly by the calcium antagonists diltiazem and nisoldipine. P...

The myocardial potassium uptake during intracoronary isoproterenol stimulation was characterized in 12 anesthetized pigs. The beta-receptor subtype specificity and the effect of adenylate cyclase activation were determined. Potassium concentrations were continuously recorded by PVC-valinomycin minielectrodes in the left atrial cavity and in coronary sinus blood diverted through a shunt to the r...

Sodium and potassium intakes were increased in normotensive volunteers to assess the effects on their blood pressures. An approximately threefold increase in sodium intake for eight days had no effect on the blood pressures of seven volunteers, while a two-stage increase in potassium intake, by about 40% for eight days and a further 55% for 14 days, had no effect on the blood pressures of 21 vo...

If a sartorius muscle of frog is pretreated for 30 min. with a hyposmotic Ringer's (called "hyposmotic potassium chloride") in which all sodium chloride is replaced by 23 mM potassium chloride, and then is immersed in normal Ringer's for about 40 min., a twitch of normal size can be elicited although the potassium contracture is almost completely abolished. During the time that this selective i...

With increasing age, plants will cause changes in soil physicochemical properties. The objective of this study was to investigate differences the properties different-aged Masson pine forest plantations (i.e., 10, 20, 40, and 60 years old). Soil samples were collected a pure plantation Southwest China. determination indexes included organic carbon, nitrogen, phosphorus potassium contents, water...

OBJECTIVES To investigate the effects of magnesium sulphate on succinylcholine-induced fasciculation in patients during the induction of general anaesthesia. METHODS The double-blind randomised clinical trial was conducted in 2012 at Tohid and Besat Hospitals in Sanandaj, Iran, on patients who were candidates for surgery under general anaesthesia. Patients were selected and divided into two e...

Four types of reaction mechanisms for the oxo ligand exchange of monomeric and dimeric neptunyl(VI) hydroxide in aqueous solution were explored computationally using density functional theory (DFT) and ab initio classical molecular dynamics. The obtained results were compared with previous studies on the oxo exchange of uranyl hydroxide, as well as with experiments. It is found that the stable ...

Isolated axons from the squid, Dosidicus gigas, were internally perfused with potassium fluoride solutions. Membrane currents were measured following step changes of membrane potential in a voltage-clamp arrangement with external isosmotic solution changes in the order: potassium-free artificial seawater; potassium chloride; potassium chloride containing 10, 25, 40 or 50, mM calcium or magnesiu...

The combination of an aldosterone receptor antagonist added to an angiotensin-converting enzyme inhibitor has been demonstrated to reduce cardiovascular and renal end points in hypertensive humans but can produce hyperkalemia in the common clinical setting of impaired renal function. We investigated the effects of dual therapy on acute and chronic potassium handling in hypertensive humans with ...