BEHAVIORAL CHARACTERIZATION OF ALPHA-ETHYLTRYPTAMINE, A TRYPTAMINE DERIVATIVE WITH MDMA-LIKE PROPERTIES IN RATS

Several reports have speculated that the tryptamine-derived drug alpha -ethyltryptamine (AET) may have effects similar to those of the amphet amine-derived drug 3,4-methylenedioxymethamphetamine (MDMA). Indeed, t he US Drug Enforcement Administration has recently placed AET on the S chedule I list because of its putative similarity to MDMA. The Behavio ral Pattern Monitor, which quantifies locomotor and investigatory resp onses of rats, was used to characterize the effects of AET in a paradi gm that distinguishes between the effects of traditional hallucinogens , amphetamine-like stimulants, and MDMA-like drugs. First, a dose-resp onse study revealed that all doses of AET tested (5, 10, 20 mg/kg) sig nificantly increased locomotor activity. Locomotor hyperactivity is pr oduced by MDMA or amphetamine-like stimulants, but not by classical ha llucinogens, such as LSD or mescaline. Additionally, AET significantly decreased measures of investigatory behavior. Similar decreases occur with MDMA or hallucinogen administration, but not with amphetamine-li ke stimulant administration. Second, as with MDMA, the locomotor hyper activity induced by AET was attenuated by pretreatment (10 mg/kg) with the serotonin reuptake inhibitor fluoxetine. Thus, AET, a tryptamine- derived drug, appears to produce an MDMA-like profile of behavioral ch anges by virtue of releasing presynaptic serotonin.