Low Serum Concentrations of Ionized Calcium in Patients with Hypertension

DISTURBANCES of calcium metabolism have been reported in both patients and animals with hypertension. In the experimental model, the abnormalities have included chronic depression of serum ionized calcium concentrations1 , 2 associated with elevated levels of parathyroid hormone,2 altered membrane binding of calcium,3 4 5 6 7 8 9 increased intestinal transport of calcium,10 hypcrcalciuria,2 and the development of nephrolithiasis.11 Similarly, enhanced parathyroid function, lower serum phosphorus concentration, and hypercalciuria12 , 13 have been reported in patients with essential hypertension. In both spontaneously hypertensive rats and patients, extracellular total calcium concentrations are similar to those in their respective normotensive controls.1 , 2 , 13 , 14 The present study was intended to extend our understanding of . . .