The effects of two single oral doses (5 mg and 20 mg) of a new angiotensin I-converting enzyme inhibitor, imidapril, on a) systemic hemodynamics (arterial pressure, heart rate, cardiac output), b) brachial and common carotid arteries' hemodynamics (diameter and blood flow, pulsed Doppler technique), c) cerebral hemodynamics (middle cerebral artery mean blood flow velocity, transcranial Doppler technique), and d) biological parameters (plasma converting enzyme activity, active plasma renin, plasma aldosterone, catecholamines, and atrial natriuretic factor) were investigated and compared with those of a placebo during the 24 h period following administration in a randomized, double-blind, cross-over study performed in six healthy volunteers. Imidapril induced a strong, dose-dependent and sustained inhibition of plasma converting enzyme activity and at the 20 mg an increase in active plasma renin. Other investigated biological parameters were not drug-affected.
View Article and Find Full Text PDF1. The effects of a single oral dose (10 mg) of ramipril on (a) systemic haemodynamics (arterial pressure, cardiac output), (b) carotid artery haemodynamics (blood flow and diameter, pulsed Doppler technique), (c) intracranial haemodynamics (middle cerebral artery mean blood velocity, transcranial Doppler technique), and (d) renin-angiotensin system (plasma converting enzyme and renin activities) have been investigated and compared with those of a placebo during the 24 h period following administration in a randomized, double-blind and cross-over study performed in six healthy volunteers. 2.
View Article and Find Full Text PDFThe systemic and regional haemodynamic and cardiac effects of two oral doses (100 and 300 mg) of a new sulphone-indolizine calcium antagonist SR 33,557 (SR) and a placebo were non invasively investigated in a double-blind, cross-over study in 6 healthy male volunteers. Arterial pressure, heart rate, cardiac output, brachial and carotid artery diameters and flows and PR and QT intervals were studied. Stroke volume, total peripheral and forearm vascular resistance, regional cardiac output distribution indices and corrected QT intervals were calculated.
View Article and Find Full Text PDFThe effects of PK 11195, a peripheral benzodiazepine receptor antagonist (200 mg orally), of nicardipine (20 mg orally), of their combination, and of a placebo on brachial and carotid arteries, diameters, and flows were determined and compared over a period of 8 h after drug intake during a double-blind and cross-over study performed on six healthy volunteers. Simultaneously, plasma concentrations of both drugs were measured. PK 11195 significantly increased carotid and more markedly brachial arteries, flows (20 and 39%, respectively), and diameters (4 and 7%, respectively) and decreased forearm vascular resistance.
View Article and Find Full Text PDFThe effects of Bay K 8644, aortic constriction, and a placebo on regional myocardial blood flows (RMBFs) and contractile function (RCF) were compared in three groups of open-chest anesthetized dogs during coronary stenosis. Bay K 8644 was investigated in two doses: 0.1 micrograms/kg, which exhibited no systemic hemodynamic effect, and 1 microgram/kg, which significantly increased arterial pressure.
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