The development of contracture related to changes of ionic environment (ionic contracture coupling) has been studied in the slowly responding fibers of frog skeletal muscle. When deprived of external ions for 30 minutes by use of solutions of sucrose, mannitol, or glucose, the slow skeletal muscle fibers, but not the fast, develop pronounced and easily reversible contractures. Partial replaceme...

Left ventricular dP/dt has been reported to be enhanced in the perfused isovolumic paced heart (Langendorff preparation) isolated from sodium-depleted rats. In this study, we tested the hypothesis that this positive inotropic effect is caused by increased responsiveness of the contractile myofilaments to calcium. To address this question, the calcium-left ventricular pressure relation during te...

The effect of different intakes of salt for 12 mo on bone calcium content and urinary excretion of calcium and hydroxyproline were examined in sham operated and oophorectomized (OX) rats to determine the long term effects of high sodium intake and its interaction with estrogen deficiency. Sham operated (n = 24) and OX (n = 24) rats were divided into groups of six rats in a 2 x 4 design. One gro...

The sodium/calcium exchanger (NCX) is a widespread transporter that exchanges sodium and calcium ions across excitable membranes. Normally, NCX mainly operates in its "forward" mode, harnessing the electrochemical gradient of sodium ions to expel calcium. During membrane depolarization or elevated internal sodium levels, NCX can instead switch the direction of net flux to expel sodium and allow...

Debaryomyces hanseniZopf isolated from the fructoplane of apples were found to be effective as biocontrol agent against rot of papaya caused by Ulocladium. chartarum(Pr.) Simm. The ability of D. hansenii to prevent infection of U. chartarum was lost when the antagonist cells were killed by autoclaving. Cell free culture filtrates of antagonist were unable to prevent disease incidence. Efficacy ...

Following blockade of membrane potassium conductance with tetraethylammonium ions or 3-aminopyridine, long-duration action potentials were recorded from mouse spinal cord neurons in primary dissociated cell culture. The action potentials were calcium-dependent since they: (1) were not blocked by the sodium-channel blocker tetrodotoxin, (2) could be recorded in sodium-free, calcium-containing me...

Calcium magnesium acetate (CMA) is environmentally benign deicing chemicals that can replace sodium chloride that is widely used on roads and highways at present for snow and ice control to provide safe driving conditions during winter. The price of CMA from petroleum-derived acetic acid is quite expensive. The bamboo vinegar is the by-product from bamboo charcoal production. The bamboo vinegar...

this study was conducted to investigate the effect of ascites-related physiological and metabolic parameters in broiler chickens fed with different components of bentonite. two hundred and seven days old arian male chicks were allocated into five dietary treatment groups including 1) basal diet (control); 2) basal diet + 1% sulphated sodium bentonite (ssb); 3) basal diet + 1% non-processed sodi...

The effects of sodium pump inhibition produced by exposure to the cardiac glycosides, ouabain or dihydroouabain, or by reduction in extracellular potassium to 1.0 mM, on contractile state and sodium-calcium exchange were studied in primary monolayer cultures of chick embryo ventricular cells. Ouabain, 10(-6)M, dihydroouabain, 5 X 10(-5)M, and extracellular potassium of 1.0 mM all induced simila...