[Behavioural effects of 8-OH-DPAT, a 5-HT1A agonist in rats and effects on the behaviour of antimanic drugs].
Effects of lithium, carbamazepine, zotepine, and clonazepam were examined on the behaviour mediated by 5-HT1A receptor and at 5-HT1A binding sites in rats. Forepaw treading, one component of 5-HT behavioural syndrome following subcutaneous injections of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), was not altered by reserpine, p-chlorophenylalanine, or alpha-methyl-p-tyrosine; in reserpine-treated rats, it was antagonized only by spiperone or by (-)-propranolol. These results indicate that 8-OH-DPAT-induced forepaw treading is produced by the direct stimulation of 5-HT1A receptor postsynaptically and also that this behaviour is not mediated by monoaminergic neurons. Lithium, carbamazepine, and zotepine inhibited forepaw treading in untreated rats; only lithium and clonazepam inhibited it in reserpine-treated rats. After 14 days treatment, only lithium enhanced it while its enhancement was abolished by reserpine. Radioligand binding studies using [3H]-8-OH-DPAT demonstrated that zotepine possessed weak affinity for 5-HT1A receptor; others lacked affinity. These results from acute experiments suggest that all drugs tested have inhibitory effects on the 5-HT1A receptor function. These effects, however, were not mediated by 5-HT1A receptor. And it is also suggested that the 5-HT1A receptor function after chronic lithium treatment might be enhanced by monoaminergic systems transsynaptically.
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology*; D002220:Carbamazepine / Q000494:pharmacology; D002998:Clonazepam / Q000494:pharmacology; D003988:Dibenzothiepins / Q000494:pharmacology; D008094:Lithium / Q000494:pharmacology; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D009281:Naphthalenes / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects*; D012110:Reserpine / Q000494:pharmacology; D012702:Serotonin Antagonists / Q000494:pharmacology*; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D014150:Antipsychotic Agents; D003988:Dibenzothiepins; D009281:Naphthalenes; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D013764:Tetrahydronaphthalenes; D002220:Carbamazepine; D002998:Clonazepam; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D012110:Reserpine; D008094:Lithium; C022172:zotepine