Head-twitch response induced by tyramine.
The intracerebroventricular (IC) administration of tyramine (TyA) induced a characteristic head-twitch response in mice pretreated with safrazine, a monoamine oxidase inhibitor. Safrazine-pretreated mice exhibited similar head-twitches following the IC treatment of serotonin (5-HT). The maximum dose of 5-HT which did not elicit head-twitches significantly potentiated TyA-induced head-twitches. Antiserotonergic drugs such as morphine and dimethothiazine antagonized TyA-induced head-twitches. A serotonergic denervator, 5,6-dihydroxytryptamine, potentiated head-twitch induced by TyA or 5-HT. Both TyA-induced and 5-HT-induced head-twitches were inhibited by dopamine and noradrenaline, while catecholaminergic denervators such as reserpine and 6-hydroxydopamine, and diethyldithiocarbamic acid, a dopamine-beta-hydroxylase inhibitor, increased the TyA response. These results indicate that head-twitches induced by TyA may be mediated via the serotonergic system and may inhibit the catecholaminergic system.
D015115:5,6-Dihydroxytryptamine / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004050:Ditiocarb / Q000494:pharmacology; D006892:Hydroxydopamines / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D012110:Reserpine / Q000494:pharmacology; D012701:Serotonin / Q000494:pharmacology; D013997:Time Factors; D014439:Tyramine / Q000008:administration & dosage / Q000494:pharmacology*
D006892:Hydroxydopamines; D012701:Serotonin; D012110:Reserpine; D004050:Ditiocarb; D015115:5,6-Dihydroxytryptamine; D014439:Tyramine