Repeated doses of MDMA (ecstasy) given to rats in a single session cause a dose-dependent increase in body temperature and long-term damage to serotonin neurons in the brain, but not to dopamine neurons. A dosing schedule of three injections of 4 mg/kg led to about a 50% loss of serotonin in the hippocampus, cortex, and striatum, while three injections of 6 mg/kg led to about a 65% loss. When rats were housed in a hot environment (30 °C), the same dose produced a larger temperature increase (up to 2.6 °C) and a 65% loss of serotonin in the cortex and hippocampus, with no loss of dopamine in the striatum.
A single dose of the recreational drug MDEA ("eve") given to Dark Agouti rats caused an acute, dose-dependent rise in body temperature. The peak hyperthermia from 35 mg/kg of MDEA matched that from 15 mg/kg of MDMA ("ecstasy"). Seven days later, MDMA caused a 50% loss of serotonin and its metabolite in the cortex, hippocampus, and striatum, indicating neurotoxic damage to serotonin nerve endings. MDEA at the highest dose produced only a 20% loss in cortex and hippocampus and no loss in striatum, with weak dose dependence. Neither drug altered striatal dopamine. MDEA had about half the potency of MDMA for hyperthermia and one-quarter the potency for serotonin neuron degeneration.