A comparison of the hypothermic effects of methylphenidate and d-amphetamine

Abstract

Methylphenidate is a central nervous system stimulant with a spectrum of action similar to the effects of d-amph tamine. d-Amphetamine-induced hypothermia is mediated via release of dopamine in the DA meso-limbic pathway. Methylphenidate causes hypothermia among rats kept at 4°C, but d-amphetamine is twice as potent as methylphenidate. Dose-response relationship of mithylphenidate thermal effects exhibits a U-shape curve. The hypoth rmic effects of 5-15 mg/kg methylphenidate are mediated by central dopaminergic neurons, as pretreatment with haloperidol inhibits these effects. The hjpothsrmia produced by lar er doses of methylphenidate is not blocked by pretreatment with haloperidol and hypothermia induced by d-amphetamine is blocked by pretreatment with haloperidol.