Neuronal mechanisms involved in drug-induced jumping behavior in mice.
Previously we have found that lithium chloride (250 mg/kg i.p.) plus haloperidol (4 mg/kg i.p.), or apomorphine (0.25 mg/kg i.p.) plus thyrotropin releasing hormone (TRH, 20 mg/kg i.p.), elicited a jumping behavior which involves dopaminergic and cholinergic inhibition, and noradrenergic activation. Pretreatment with antiserotonergic agents such as methysergide (5 and 10 mg/kg i.p.) and cyproheptadine (5 mg/kg i.p.) enhanced the jumping behavior induced by these drugs. 5-Methoxy-N,N-dimethyltryptamine (5-MDMT, 5 mg/kg i.p.), a serotonergic receptor agonist, inhibited the jumping behavior. Muscimol, a GABA receptor agonist, at 2 mg/kg, potentiated jumping. GABA receptor antagonists such as bicuculline (4 mg/kg i.p.) and picrotoxin (0.2 and 1 mg/kg i.p.) depressed jumping. An antihistamine agent, diphenhydramine (5 mg/kg i.p.), also potentiated the jumping behavior. Furthermore methysergide (10 mg/kg i.p.), but not muscimol (2 mg/kg i.p.) elicited jumping behavior when combined with clonidine (0.5 mg/kg i.p.), TRH (20 mg/kg i.p.), haloperidol (4 mg/kg i.p.) or atropine (5 mg/kg i.p.). These results suggest that in addition to dopaminergic, cholinergic and noradrenergic mechanisms, serotonergic inhibition may be directly contributing to the initiation of jumping behavior, whereas GABAergic activation appears to be a modulating factor in this behavior.
Ushijima
I
I
Mizuki
Y
Y
Yamada
M
M
Glavin
G B
GB
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006220:Haloperidol / Q000494:pharmacology; D008094:Lithium / Q000494:pharmacology; D008297:Male; D008784:Methysergide / Q000494:pharmacology; D051379:Mice; D008815:Mice, Inbred Strains; D009043:Motor Activity / Q000187:drug effects*; D009118:Muscimol / Q000494:pharmacology; D011963:Receptors, GABA-A / Q000187:drug effects / Q000502:physiology*; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology*; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology
D011963:Receptors, GABA-A; D011985:Receptors, Serotonin; D009118:Muscimol; D013973:Thyrotropin-Releasing Hormone; D008094:Lithium; D006220:Haloperidol; D001058:Apomorphine; D008784:Methysergide