Intracellular Electrolytes During Antihypertensive Treatment with a Loop Diuretic

Abstract

 

The effect of the loop diuretic, piretanide (12 mg/day on blood pressure and intracellular electrolyte composition in red blood cells during a six-week treatment period was studied in 14 previously untreated essential hypertensive patients. Blood pressure fell continuously during the six weeks, intracellular Na⁺ activity in red blood cells increased slightly (P < 0.05), and there was a marked decrease in intracellular Ca²⁺ activity (P < 0.01). Intracellular K⁺ concentration was not altered. It is concluded therefore, that intracellular free Na⁺ does not correlate with the actual blood pressure, whereas the fall in blood pressure is associated with a decrease in intracellular free Ca²⁺, suggesting that intracellular free Ca²⁺ is involved in the regulation of vascular tone.

Journal of Hypertension 2:393-395, 1984