title: Effects of dihydropyridine drugs on reversal by imipramine of helpless behavior in rats.
abstract: The present study was undertaken in order to determine the effects of the dihydropyridine calcium channel blocker, nimodipine and the dihydropyridine calcium channel activator BAY k 8644, in the learned helplessness test in the rat. Nimodipine dose dependently (0.5-2 mg/kg per day) reversed the behavioral deficit induced by inescapable shocks. The reversal of helpless behavior by imipramine (32 mg/kg per day) was antagonized by BAY k 8644 (0.5 and 1 mg/kg per day), and the effects of imipramine 8 and 16 mg/kg per day) were potentiated by a subeffective dose (0.5 mg/kg per day) of nimodipine. These results suggest that central dihydropyridine binding sites may be specifically involved in the modulation of the imipramine reversal of helpless behavior and favor a physiological role for dihydropyridine binding sites in the brain.
authors: Département de Pharmacologie, Faculté de Médecine Pitié-Salpêtrière, Paris, France.
authors: P
authors: P
authors: Martin
authors: S
authors: S
authors: Laurent
authors: J
authors: J
authors: Massol
authors: M
authors: M
authors: Childs
authors: A J
authors: AJ
authors: Puech
mesh_terms: D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D004095:Dihydropyridines / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004597:Electroshock; D006380:Helplessness, Learned / Q000523:psychology*; D007099:Imipramine / Q000494:pharmacology*; D008297:Male; D009553:Nimodipine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004095:Dihydropyridines; D009553:Nimodipine; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D007099:Imipramine