Author:

Keywords:

Angiotensin-Converting Enzyme Inhibitors, Calcium, Captopril, Cell Membrane, Erythrocytes, Humans, Hypertension, Male, Middle Aged, Sodium-Hydrogen Antiporter, Science & Technology, Life Sciences & Biomedicine, Pharmacology & Pharmacy, Na+/H+-exchange, Ca2+-efflux, ACE inhibition, captopril, SPONTANEOUSLY HYPERTENSIVE RATS, CAPTOPRIL, CALCIUM, COTRANSPORT, ENALAPRIL, ATPASE, AORTA, Sodium-Hydrogen Exchangers, 1115 Pharmacology and Pharmaceutical Sciences, 3214 Pharmacology and pharmaceutical sciences

Abstract:

The effect of the angiotensin-converting enzyme inhibitor, captopril, on Na+/H(+)-exchange activity and on Ca(2+)-ATPase mediated Ca(2+)-efflux was investigated in red blood cell membranes of patients with essential hypertension. The erythrocyte Na+/H(+)-exchange rate was measured as the difference in H(+)-efflux rate when measured in the presence or absence of Na+. The erythrocyte Ca(2+)-transport mediated by Ca(2+)-ATPase was assayed as the erythrocyte Ca(2+)-efflux rate. Our data show that captopril, in vitro and in vivo, inhibits the Ca(2+)-ATPase mediated Ca(2+)-efflux rate in human erythrocytes, while in vivo it stimulates the erythrocytes Na+/H(+)-exchange rate.