We have investigated the kinetics of mitochondrial Ca(2+) influx and efflux and their dependence on cytosolic [Ca(2+)] and [Na(+)] using low-Ca(2+)-affinity aequorin. The rate of Ca(2+) release from mitochondria increased linearly with mitochondrial [Ca(2+)] ([Ca(2+)](M)). Na(+)-dependent Ca(2+) release was predominant al low [Ca(2+)](M) but saturated at [Ca(2+)](M) around 400muM, while Na(+)-i...

We present high resolution spectral observations of the absorption lines of Ca II and Na I associated with the circumstellar disk surrounding the starβ Pictoris. The observations were taken over a four night period in January 1996 and reveal substantial profile variability between successive nights. High velocity absorption features at velocities of +58 km s−1 were observed in the Ca II data, b...

Electrolyte fluxes are fundamental to normal endocrine pancreatic function. Adenosine triphosphatases (ATPases) are enzyme systems believed to modulate electrolyte movements across membranes in a number of cell types. This study was undertaken to measure cation-dependent ATPases of rat pancreatic islets. In addition, we compared effects of substances which influence endocrine pancreatic functio...

X-ray microanalysis of freeze-dried labial gland cryosections revealed that Na concentration was doubled and the Ca/S concentration ratio was decreased in secretory granules of labial glands from patients with cystic fibrosis (CF) when compared with glands from normal subjects. Other results suggested that the decrease in the Ca/S concentration ratio resulted from an increase in S concentration...

Atomic absorption spectrometry was used to measure magnesium, calcium, and sodium, and emission spectrometry to measure potassium, in myocardium (left and right ventricles) of 26 control subjects who died of acute trauma. Results were expressed in mumol/g of proteins. Mg/Ca and K/Na ratios were also determined. The same measurements were made in 24 patients who died from acute myocardial infarc...

Remarkably dynamic Ca z ÷ fluxes control Ca 2 ÷ homeostasis in the outer segments of vertebrate rod photoreceptors (ROS). Ca 2 ÷ fluxes are believed to be carried by only two different membrane proteins embedded in the ROS plasma membrane; these two proteins as well as some of the other main molecular components of ROS are schematically depicted in Fig. 1. ROS are the sites of the process of vi...

In microinjected Myxicola giant axons with elevated [Na]i, Na efflux was sensitive to Cao under some conditions. In Li seawater, sensitivity to Cao was high whereas in Na seawater, sensitivity to Cao was observed only upon elevation of [Ca]o above the normal value. In choline seawater, the sensitivity of Na efflux to Cao was less than that observed in Li seawater whereas Mg seawater failed to s...

salt stress is one of the most chalanging abiotic stresses affecting natural productivity and causing significant croplosses worldwide. a greenhouse experiment was conducted to evaluate the response of two alfalfa cultivars (bamiand hamedani) to 6 levels of salinity (0 as control, 25, 50, 75, 100, 125 mm nacl) at the college of agriculture,shiraz university, shiraz, iran in 2008. plant dry weig...

Little is known about the role of mitogen-activated protein kinase 6 (MPK6) in Na(+) toxicity and inhibition of root growth in Arabidopsis under NaCl stress. In this study, we found that root elongation in seedlings of the loss-of-function mutants mpk6-2 and mpk6-3 was less sensitive to NaCl or Na-glutamate, but not to KCl or mannitol, as compared with that of wild-type (WT) seedlings. The less...

an experiment was conducted in algerian desert goats to study the effect of age and season on blood biochemical and mineral profile during different physiological stages of the goats. serum ca, mg and na levels were significantly high at birth and decreases as the age advanced. the season had a significant effect on the decreased levels of ca, mg and k and inversely on the increased levels of n...