title: Effect of prazosin and oxprenolol on plasma renin activity and blood pressure in patients with essential hypertension.
abstract: 48 patients with normal-renin essential hypertension were treated with prazosin alone or in combination with oxprenolol. 1 h after a single dose of 2 mg prazosin tachycardia and a decrease in blood pressure developed. Renin activity in the peripheral plasma (PRA) increased from 1.04 +/- 0.15 to 2.64 +/- 0.20 ng AgT/ml/h. A 3-day treatment with 2 mg t.i.d. prazosin of 11 patients caused no further decrease in blood pressure, while PRA returned to the baseline level. Treatment for 3 days with 2 mg prazosin t.i.d. and 40 mg oxprenolol t.i.d. of 37 patients further decreased blood pressure as well as PRA. The increase in PRA after a single dose of prazosin could be related to the enhanced sympathetic activity. The decreased PRA after prazosin + oxprenolol therapy may be one of the factors responsible for the greater antihypertensive response to the combined therapy.
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010096:Oxprenolol / Q000494:pharmacology* / Q000627:therapeutic use; D011224:Prazosin / Q000009:adverse effects / Q000494:pharmacology* / Q000627:therapeutic use; D011799:Quinazolines / Q000494:pharmacology*; D012083:Renin / Q000097:blood*
chemical_list: D011799:Quinazolines; D010096:Oxprenolol; D012083:Renin; D011224:Prazosin