Membrane Handling of Calcium in Essential hypertension

Abstract

The relationship between cytosolic free Ca⁺⁺ and increase in blood pressure may hold the key to unravel the causes and origin of essential hypertension. In 20, essential hypertensive patients and 25 normotensive controls, total serum calcium, serum ionized calcium and free erythrocyte intracellular Ca⁺⁺, were measured. For calcium loading, lonophore A23187 was used. Intracellular Ca⁺⁺ was measured by ion selective electrodes, which showed a highly significant increase in hypertensive patients as compared to normotensive controls. [1.00±0.11 versus 0.72±0.O6mmol/L]. While total serum calcium showed no significant difference, serum ionized Ca⁺⁺ was significantly decreased in hypertensives as compared to controls. [1.028±0.11 versus 1.22±0.13mmol/L].The present results confirm an association between elevated erythrocyte Ca⁺⁺ and essential hypertension. If generalized, the defect could lead to raised intracellular Ca⁺⁺ in smooth muscle causing increased vascular tone and arterial hypertension.