Digoxin without effect on renin release in healthy subjects.

In the clinical evaluation of renin status, the effect of chronic digitalization is unknown. A 50 per cent decrease in PRA is presented after intravenous digoxin injection. In this study the acute intake of 0.75 mg digoxin decreased PRA slightly (p less than 0,05), but no difference could be found in ten healthy volunteers in regard to PRA after placebo, randomly examined twice after digoxin and once after placebo tablets. Eight healthy volunteers were digitalized with 2.5 mg digoxin in total during four days. Renin release was stimulated by ergometric exercise (900 kpm for 10 min) before and after digitalization, when the mean serum digoxin concentration was 2.0 +/- 0.2 ng/ml (SEM). No difference in basal or exercise-stimulated PRA could be found after digoxin. We conclude that the steady state digitalis therapy does not interfere with renin release. The peripheral vasoconstriction accompanied with the acute intravenous digitalis administration can lead to a transient decrease of PRA.