Ionized calcium is critical to the maintenance of normal cardiovascular function. Recently, vasoactive properties have also been attributed to parathyroid hormone (PTH). The present study characterizes the calcium-PTH axis in the spontaneously hypertensive rat (SHR) in order to determine the effects of chronic alterations in calcium intake on the development and maintenance of hypertension in t...

Multiple linear regression analysis showed that total calcium was significantly and positively related to albumin, globulin, anion gap, and bicarbonate in plasma from 556 normal postmenopausal women. The residual constant of 1.21 mmol/L approximated the normal mean for ionized calcium in plasma. The coefficients derived from the multiple regression analysis were used to calculate ionized calciu...

BACKGROUND Ionized calcium concentration is the gold standard to assess calcium status in dogs, but measurement is not always available. OBJECTIVES (1) To predict ionized calcium concentration from biochemical results and compare the diagnostic performance of predicted ionized calcium concentration (piCa) to those of total calcium concentration (tCa) and 2 corrected tCa formulas; and (2) to s...

We describe a method for ultrafiltrable calcium involving the use of Worthington Ultrafree Anticonvulsant Drug Filters. When measured at 37 degrees C, with mineral oil covering the sample to prevent loss of CO2, values for ultrafiltrable calcium correlated reasonably well (r = 0.91) with those for ionized calcium as measured with an ion-selective electrode. All patients' samples with significan...

We examined changes in ionized calcium concentration in serum after its exposure to air. Samples with total protein concentrations ranging from 50 to 90 g/liter were equilibrated with CO2 in nitrogen (5/95, by vol) or CO2 alone, to produce pH values of 7.0 to 8.0. Ionized calcium was then measured with an Orion flow-through electrode system. Curves relating pH and ionized calcium concentration ...

BACKGROUND Calcium is known to be major mediator in ischemic neuronal cell death. Recent studies have shown that elevated serum calcium levels at admission in patients with stroke have been associated with less severe clinical deficits and with better outcomes. AIM The aim of this to determine the correlation between serum calcium (total, corrected, and ionized) and infarct size (IS) in patie...

White matter lesions have detrimental effects upon older adults, while serum calcium levels have been associated with elevated vascular risk and may be associated with these lesions. Depression, a serious mental disorder characterized by disturbances in calcium metabolism, may be an important contributor to any calcium-lesion relationship. This cross-sectional pilot study examined the associati...

An oral calcium bolus (Bovikalc, Boehringer Ingelheim Vetmedica) supplying calcium to dairy cows in the form of calcium chloride and calcium sulfate was evaluated to determine the effect on calcium homeostasis immediately after calving. Cows in the treatment group received one bolus immediately after calving and a second bolus 12 hours later. Control cows received no calcium supplementation. Bl...

OBJECTIVE The aim of the present study was to identify a fast, efficient and low-cost method to diagnose hypoparathyroidism after total thyroidectomy. MATERIALS AND METHODS One hundred and forty medical records, which contained patients' clinical and laboratory data, were retrospectively analyzed. Patient parathyroid hormone values, which were obtained immediately following operation, were co...

Changes in ionized calcium were studied in axons isolated from living squid by measuring absorbance of the Ca binding dye Arsenazo III using multiwavelength differential absorption spectroscopy. Absorption changes measured in situ were calibrated in vitro with media of ionic composition similar to axoplasm containing CaEGTA buffers. Calcium loads of 50-2,500 mumol/kg axoplasm were induced by mi...