Effects of enalapril on blood pressure and renal haemodynamics in essential hypertension.

The effects of enalapril were assessed in a double-blind study versus propranolol. Twenty-two patients with essential hypertension were titrated with either enalapril (5, 10 and 20 mg twice daily) or propranolol (40, 80 and 120 mg twice daily). With propranolol blood pressure decreased from 154/101 +/- 4/1 to 146/98 +/- 5/2 mmHg (mean +/- SEM); with enalapril it decreased from 151/103 +/- 3/1 to 134/92 +/- 4/2 mmHg, both after 12 weeks of therapy. Effective renal plasma flow remained unchanged in the propranolol group whereas it increased from 413 +/- 19 to 445 +/- 27 ml/min (p less than 0.05) with enalapril. Glomerular filtration rate remained unchanged at either medication. Enalapril is an effective anti-hypertensive agent with a favourable effect on renal haemodynamics.