The effect of magnesium sulphate in releasing calcium emission from interference by phosphate and sulphate has been investigated. Samples were diluted in 10 mM MgSO(4), 2 mM NaCl, giving final calcium concentrations of about 0.05 to 0.10 mM. In this diluent, galvanometer readings were proportional to calcium concentrations up to 0.4 mM. The magnesium sulphate released calcium emission from depr...

OBJECTIVE The diagnosis of primary hyperparathyroidism (PHP) can be difficult in patients with normal plasma calcium or parathyroid hormone (PTH) levels. We perfected a standardized short-time i.v. calcium loading test in healthy controls (HC) and compared the results with those of patients with PHP. METHODS Sixteen HC received 0.33 mmol/kg calcium gluconate intravenously for 3 h. Plasma calc...

The effects of providing ultraviolet (uv) radiation (285 to 315 nm, ultraviolet B) on calcium metabolism in two groups of 20 healthy grey parrots (Psittacus e erithacus) fed either a seed or pellet-based diet were investigated. There was a significant increase in the concentration of ionised calcium in the plasma of both groups, independent of the calcium and vitamin D(3) content of the diets f...

THE diagnosis of primary hyperparathyroidism has been classically based upon the demonstration of high plasma calcium and low plasma phosphorus concentrations and an excessive urinary excretion of calcium. In recent years, however, it has become recognized that patients with primary hyperparathyroidism may present with plasma calcium concentrations that are within the normal range (George et al...

in order to determine calcium (ca), magnesium (mg) content and total antioxidant capacity (tac) of seminal plasma in buffalo and to study their associations with the semen characteristics, 54 semen samples were collected from 10 buffalo bulls; semen quality was evaluated, seminal plasma was then harvested by centrifugation and its ca and mg content were estimated and its tac determined. the ca ...

in previous studies, mebudipine, a dihydropyridine calcium channel blocker, showed a considerable potential to be used in cardiovascular diseases. the aim of the current study was to develop a valid method using reversed-phase high performance liquid chromatography coupled with electrospray ionization mass spectrometry to assay mebudipine in the human plasma. separation was achieved on a zorbax...

We have examined changes in plasma concentrations of calcium in seven anaesthetized pigs during i.v. infusion of irrigating fluid containing 1.5% glycine. Volumes infused were 875 ml at 20 min (22 ml kg-1), 1475 ml at 40 min and 2075 ml at 60 min (75 ml kg-1). Plasma concentrations of sodium decreased from 134.5 (SD 3.4) to 112.8 (6.7) mmol litre-1 at 60 min and correlated with the volume of gl...

The brain contains glial cells. Astrocytes, a type of glial cell, have long been known to provide a passive supportive role to neurons. However, increasing evidence suggests that astrocytes may also actively participate in brain function through functional interactions with neurons. However, many fundamental aspects of astrocyte biology remain controversial, unclear and/or experimentally unexpl...

We examined the contribution of the primary hormones of calcium homeostasis to the control of calcium intake in the rat. Male Sprague-Dawley rats with 50 mM CaCl2 solution as their only source of calcium received subcutaneous hormone infusions for 13 days. Parathyroid hormone (PTH; 40, 80, or 160 ng/h) produced sustained dose-related decreases in CaCl2intake. High doses of calcitonin (CT; 32 or...

Plasma calcium concentration is maintained within a narrow range (8.5-10.5 mg/dL) by the coordinated action of parathyroid hormone (PTH), 1,25(OH)2D3, calcitonin, and ionized calcium (iCa(2+)) itself. The kidney plays a key role in this process by the fine regulation of calcium excretion. More than 95% of filtered calcium is reabsorbed along the renal tubules. In the proximal tubules, 60% of fi...