Rapid desensitization of central beta-adrenoceptors in rat after subacute treatment with imipramine and calcium entry blockers.
Neuropharmacology
; 30(8): 879-85, 1991 Aug.
Article
em En
| MEDLINE
| ID: mdl-1664072
ABSTRACT
The subcutaneous (s.c.) administration of isoprenaline to rats produced a dose-dependent increase in water drinking which was effectively antagonized by propranolol. This dipsogenic response was significantly inhibited after the intraperitoneal (i.p.) administration of imipramine (15 mg/kg/day), together with either of the following calcium entry blockers, for four days diltiazem (15 mg/kg/day), verapamil (10 mg/kg/day), nifedipine (10 mg/kg/day) or nicardipine (15 mg/kg/day). Simultaneous injection of the inhibitor of the synthesis of serotonin, p-chlorophenylalanine (200 mg/kg/day, i.p.), did not affect this attenuation of the isoprenaline-induced response. Similarly, the selective 5-HT2 receptor agonist, 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane (DOM) or the 5-HT2 receptor antagonist, ketanserin, had no significant effect on the attenuation of isoprenaline-induced drinking behaviour. The inhibition of isoprenaline-induced drinking, was, however, effectively attenuated after treatment of the animals with 6-hydroxydopamine (2.5 micrograms) or clonidine (30 micrograms), injected intracerebroventricularly (i.c.v.). These results indicate that the calcium entry blockers accelerate the desensitization of central beta-adrenoceptors possibly by an action on central adrenoceptors of the rat.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bloqueadores dos Canais de Cálcio
/
Receptores Adrenérgicos beta
/
Comportamento de Ingestão de Líquido
/
Imipramina
Limite:
Animals
Idioma:
En
Revista:
Neuropharmacology
Ano de publicação:
1991
Tipo de documento:
Article