Cardiovascular response to exercise and regional haemodynamics during treatment with prizidilol hydrochloride (SK & F 92 657) in moderately severe essential hypertension.
Fourteen men with moderately severe essential hypertension were treated with prizidilol hydrochloride 400-700 mg once daily (mean +/- S.D. 612 +/- 56 mg/day). The study was open and ambulatory, with an initial placebo period followed by dose titration of prizidilol. Prior to treatment and during optimal control of blood pressure cardiovascular adaptation was examined in a submaximal exercise test. Plethysomographic assessment of vascular flow, resistance and tone in the calf musculature during supine rest and during maximal vasodilatation was also performed. A highly significant reduction in systolic (from 164 +/- 4.5 to 141 +/- 2.7 mmHg; p less than 0.001) and diastolic blood pressure (from 105 +/- 1.6 to 87 +/- 1.3 mmHg; p less than 0.001) at supine rest was noted during therapy with prizidilol. There was no significant change in heart rate. Systolic pressure in the standing position was reduced (from 159 +/- 4.2 to 139 +/- 2.9 mmHg; p less than 0.001) and so was the diastolic pressure (from 111 +/- 2.5 to 95 +/- 1.9 mmHg; p less than 0.001). The heart rate in the standing position was significantly increased compared to supine rest in the placebo period and during optimal treatment with prizidilol. The beta-adrenoceptor blocking properties of prizidilol were apparent as a reduction in the exercise-induced heart rate response at even the lowest work load. During prizidilol therapy an increase in resting calf muscle blood flow was found from 3.1 +/- 1.5 ml/min X 100 ml to 4.3 +/- 2.1 ml/min X 100 ml (p less than 0.025). Vascular resistance and vascular tone were significantly reduced.(ABSTRACT TRUNCATED AT 250 WORDS)
D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D005080:Exercise Test; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion; D011724:Pyridazines / Q000627:therapeutic use*; D012039:Regional Blood Flow / Q000187:drug effects; D013997:Time Factors
D000959:Antihypertensive Agents; D011724:Pyridazines; C024293:prizidilol