Cardiovascular effects of intracerebroventricular injections of (+/-)-nebivolol and its enantiomers--a comparison with those of metoprolol in the rat.
The cardiovascular effects of (+/-)-nebivolol, a potent beta 1-adrenoceptor antagonist, and its enantiomers, (+)-nebivolol (SRRR) and (-)-nebivolol (RSSS) in normotensive anaesthetized rats, have been investigated using metoprolol as a reference substance. The drugs decreased blood pressure and heart rate immediately after i.c.v. injection. These effects paralleled the beta-blocking potencies ((+)- greater than (+/-)-greater than (-)-nebivolol). Metoprolol induced a weaker hypotension than (+/-)-nebivolol, and a long-lasting reduction in stroke volume. As reported after i.v. administration, (+/-)-nebivolol and isomers by the i.c.v. route decreased peripheral vascular resistance following i.c.v. administration while metoprolol increased it. These effects are centrally mediated since cardiovascular responses to isoprenaline i.v. remained unchanged.
Laboratoire de Pharmacologie, Faculté de Pharmacie, URA-CNRS 594, Châtenay-Malabry, France.
M
M
Midol-Monnet
M
M
Davy
M
M
Heimburger
F
F
Beslot
Y
Y
Cohen
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001578:Benzopyrans / Q000008:administration & dosage / Q000494:pharmacology*; D004983:Ethanolamines / Q000008:administration & dosage / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects*; D006439:Hemodynamics / Q000187:drug effects*; D007276:Injections, Intraventricular; D008297:Male; D008790:Metoprolol / Q000494:pharmacology*; D000068577:Nebivolol; D051381:Rats; D011919:Rats, Inbred Strains; D013237:Stereoisomerism
D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D001578:Benzopyrans; D004983:Ethanolamines; D000068577:Nebivolol; D008790:Metoprolol