Serotonin2 (5-HT2) receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) inhibits chlorpromazine- and haloperidol-induced hypothermia in mice.

Chlorpromazine- and haloperidol-induced hypothermia were examined in mice. The alpha 1 receptor agonist phenylephrine partially antagonized the hypothermia, while the dopamine D2 receptor agonist apomorphine did not inhibit it. The central serotonin2 (5-HT2) receptor agonist I-2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) strongly inhibited the chlorpromazine- and haloperidol-induced hypothermia. Both drugs at doses which can elicit hypothermia antagonized head twitch responses mediated by the central 5-HT2 receptor. These results suggest that the chlorpromazine- and haloperidol-induced hypothermia may be mediated by the blockade of the central 5-HT2 receptor.