Differential effects of 5-hydroxytryptaminergic antagonists upon apomorphine- and lergotrile-induced hypothermia and stereotyped behaviour in rats.
The dopaminergic stimulants apomorphine and lergotrile both evoked hypothermia and stereotyped behaviour in rats. These drug effects were sensitive to antagonism by haloperidol, a dopaminergic receptor blocker. In rats pretreated with 5-hydroxytryptaminergic receptor blockers, cinanserin reduced apomorphine-induced hypothermia but cyproheptadine did not. Both cinanserin and cyproheptadine significantly potentiated lergotrile-induced hypothermia. Similarly, the stereotypic effects of apomorphine were partly reduced by cyproheptadine, although higher doses of cyproheptadine did potentiate lergotrile-induced stereotyped behaviour. These findings of different influences of 5-HT antagonists upon the effects of apomorphine and lergotrile indicate that these two dopaminergic stimulants may not work in identical manner to produce outwardly similar drug effects.
D006916:5-Hydroxytryptophan / Q000037:antagonists & inhibitors*; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001831:Body Temperature / Q000187:drug effects*; D002928:Cinanserin / Q000494:pharmacology; D003533:Cyproheptadine / Q000494:pharmacology; D004873:Ergolines / Q000031:analogs & derivatives* / Q000494:pharmacology; D006220:Haloperidol / Q000494:pharmacology; D006801:Humans; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013239:Stereotyped Behavior / Q000187:drug effects*
D004873:Ergolines; D003533:Cyproheptadine; D006916:5-Hydroxytryptophan; D006220:Haloperidol; D002928:Cinanserin; D001058:Apomorphine; C031875:lergotrile