ISSN:
1432-1041
Keywords:
Dilevalol
;
Propranolol
;
intrinsic sympathomimetic activity
;
healthy volunteers
;
pulsed Doppler
;
regional haemodynamics
;
plasma renin activity
;
plasma atrial natriuretic factor
;
plasma norepinephrine
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract The effects of single oral doses of dilevalol 400 mg and propranolol 80 mg on systemic and regional haemodynamics at rest and after sub-maximal exercise, were compared, in a placebo-controlled, randomised, double-blind, crossover study in 6 healthy male volunteers. At rest, as compared to placebo, neither dilevalol nor propranolol significantly affected arterial pressure and heart rate but, whereas propranolol decreased cardiac output (−27% at 2 h) and tended to increase total peripheral resistance, dilevalol tended to increase cardiac output and decreased total peripheral resistance (−7% at 2 h). Neither dilevalol nor propranolol affected brachial artery diameter. Propranolol tended to decrease brachial artery flow (−20% at 2 h) and to increase brachial vascular resistance (+25% at 2 h), but dilevalol did not and the brachial irrigation ratios did not change. Neither of the drugs affected carotid haemodynamics or plasma atrial natriuretic factor. Both drugs tended to decrease plasma renin activity, and dilevalol (+82% at 2 h) increased norepinephrine more than propranolol (+19% at 2 h). After exercise, dilevalol and propranolol produced similar falls in the induced increases in arterial pressure, heart rate and cardiac output, and had the same effects on regional haemodynamics, plasma renin activity and atrial natriuretic factor. Finally, dilevalol greatly increased plasma norepinephrine. We conclude that the β2-adrenoceptor agonist activity of dilevalol was clearly expressed at rest, thus inducing vasodilation and counteracting the β-adrenoceptor blockade-induced negative chronotropic and inotropic effects. However, during sub-maximal exercise, only the β-adrenoceptor antagonist activity of dilevalol was apparent.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00193476
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