MK-801 and dopaminergic system in electrically-induced convulsions in mice.
In this study, the effects of MK-801 and selective dopaminergic agents on electrically-induced convulsions in mice were examined. MK-801 (0.004-0.1 mg/kg, ip) showed significant and dose-dependent anticonvulsive effects, and the anticonvulsive effects of MK-801 (0.02 mg/kg, ip) were not antagonized by dopamine selective antagonists, SCH-23390 (D1, 0.1 mg/kg, sc), sulpiride (D2, 100 mg/kg, sc) and pimozide (D2, 0.5 mg/kg, sc). Apomorphine (0.02-0.5 mg/kg, sc), a D1/D2 agonist, showed proconvulsant effect on electrically-induced convulsions. Dopamine selective antagonists, SCH-23390 (0.02-0.5 mg/kg, sc), sulpiride (5-100 mg/kg, sc) and pimozide (0.1-2.5 mg/kg, ip), also showed proconvulsant effect. However, these effects of dopamine agonist and antagonists were not dose-dependent. These findings suggest that the dopaminergic system neither plays an inhibitory role, at least on electrically-induced convulsions in mice, nor contributes to the anticonvulsant effect of MK-801 in electrically-induced convulsions.
Yokoyama
H
H
Department of Pediatrics, School of Medicine, Tohoku University, Sendai, Japan.
Onodera
K
K
Iinuma
K
K
D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology*; D001552:Benzazepines / Q000494:pharmacology; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004597:Electroshock; D008297:Male; D051379:Mice; D010868:Pimozide / Q000494:pharmacology; D011954:Receptors, Dopamine / Q000187:drug effects; D013469:Sulpiride / Q000494:pharmacology
D000927:Anticonvulsants; D001552:Benzazepines; D011954:Receptors, Dopamine; D010868:Pimozide; D016291:Dizocilpine Maleate; D013469:Sulpiride