The renal effects of clonidine in unanesthetized rats

Détails

ID Serval
serval:BIB_0D4795CEE57B
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
The renal effects of clonidine in unanesthetized rats
Périodique
European Journal of Pharmacology
Auteur(s)
Biollaz  J., Roch-Ramel  F., Kirchertz  E. J., Atkinson  J., Peters-Haefeli  L.
ISSN
0014-2999 (Print)
Statut éditorial
Publié
Date de publication
10/1979
Volume
58
Numéro
4
Pages
407-18
Notes
Journal Article --- Old month value: Oct 15
Résumé
Clonidine s.c. (0.01-0.3 mg/kg), in unanesthetized rats, caused an initial rise (+20 mm Hg), followed by a continuous fall of BP and a dose-dependent natriuresis and diuresis for up to 2 h. Glomerular filtration rate (GFR) (CIn) increased during the first 20 min, while effective renal plasma flow (ERPF) (CPAH) remained normal. Subsequently, between 20 and 60 min after injection, ERPF (CPAH) decreased considerably while GFR had reverted to its normal value. In saline-infused rats clonidine diuresis was accompanied by an "inappropriate" positive free water clearance. Pentobarbital anesthesia suppressed the initial BP peak and the diuresis. Phenoxybenzamine (1 mg/kg i.v.) was antinatriuretic in saline diuresis; the effect of phenoxybenzamine + clonidine on diuresis and salt excretion represented the sum of the effects of both drugs, but phenoxybenzamine enhanced the clonidine-induced increase of GFR. Neither haloperidol (1 mg/kg i.v.) nor bulbocapnine (3 mg/kg i.v.) interfered with the renal effects of clonidine. Clonidine s.c. caused hyperglycemia and glucosuria which did not account for the natriuresis. Clonidine thus appears to increase the GFR and "filtration fraction" (FF) by a phenoxybenzamine-insensitive rise of glomerular ultrafiltration, to depress ERPF by alpha-adrenergic afferent vasoconstriction, to induce natriuresis by a tubular action not blocked by phenoxybenzamine and to exert an antivasopressin effect, either by depressing pituitary vasopressin secretion or the renal response to vasopressin.
Mots-clé
Animals Aporphines/pharmacology Blood Pressure/drug effects Clonidine/*pharmacology Diuresis/drug effects Dopamine/pharmacology Female Haloperidol/pharmacology Kidney/*drug effects Male Phenoxybenzamine/pharmacology Potassium/urine Rats Time Factors
Pubmed
Web of science
Création de la notice
25/01/2008 11:41
Dernière modification de la notice
20/08/2019 13:34
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