Although the exact mechanisms involved in the serotonergic neurotoxicity produced by substituted amphetamines are not completely known, evidence suggests that oxidative and/or bioenergetic stress may contribute in the mechanism of neurotoxicity of 3,4-methylenedioxymethamphetamine (MDMA). It has been postulated that MDMA-induced hyperthermia also contributes to the MDMA-induced neurotoxicity. MDMA produces brain glycogenolysis, and MDMA-induced hyperthermia appears to mediate this effect. The relationship of MDMA-induced hyperthermia and glycogenolysis in the serotonergic neurotoxicity of MDMA was investigated in the present study. The administration of MDMA (20 mg/kg sc) at an ambient temperature of 24 degrees C produced hyperthermia and brain glycogenolysis in Postnatal Day (PND)21 and PND70 rats; however, long-term reductions in serotonin (5-HT) concentrations in the striatum were detected only in the PND70 rats. Treatment of PND21 and PND70 rats with MDMA at 17 degrees C resulted in neither hyperthermia nor glycogenolysis; nevertheless, long-term reductions in 5-HT concentrations were still evident in the PND70 rats treated with MDMA. These results support the conclusion that hyperthermia, as well as glycogenolysis, are neither necessary nor sufficient in the serotonergic neurotoxicity of MDMA.
Copyright 2004 Elsevier Inc.