[The hypokalemic effect of adrenaline is increased by nitrendipine in normal man]

Calcium blockers of the dihydropyridine group may affect serum potassium level through an influence on the epinephrine mediated fall in serum K+. The effect of epinephrine infusion (12.5, 25 and 50 ng/kg/min) was assessed during placebo and after a 4-day treatment by nitrendipine in normal man. Nitrendipine treatment was associated with an enhancement in the fall of serum potassium induced by epinephrine. By contrast the response of arterial pressure, heart rate as well as the increase in blood glucose, plasma renin activity and the fall in plasma aldosterone and serum insulin levels induced by epinephrine were not affected by nitrendipine. Nitrendipine may potentiate the Na, K-ATPase stimulatory effect of epinephrine. Serum potassium should be carefully monitored in clinical situations associated with a consistent increase in circulating levels of epinephrine.