The abuse liability profile of three synthetic hallucinogens, N,N-diisopropyltryptamine (DIPT), 5-methoxy-N,N-diethyltryptamine (5-MeO-DET), and 5-methoxy-α-methyltryptamine (5-MeO-AMT) was tested in rats trained to discriminate hallucinogenic and psychostimulant compounds, including cocaine, methamphetamine, 3,4-methylenedioxymethylamphetamine (MDMA), lysergic acid diethylamide (LSD), (-)-2,5-dimethoxy-4-methylamphetamine (DOM), and dimethyltryptamine (DMT). Because abused hallucinogens act at 5-HT1A and 5-HT2A receptors, and abused psychostimulants act at monoamine transporters, binding and functional activities of DIPT, 5-MeO-DET, and 5-MeO-AMT at these sites were also tested. DIPT fully substituted in rats trained to discriminate DMT (ED50= 1.71 mg/kg) and DOM (ED50 = 1.94 mg/kg), but produced only 68% LSD-appropriate responding. 5-MeO-DET fully substituted for DMT (ED50 = 0.41 mg/kg) and produced 59% MDMA-appropriate responding. 5-MeO-AMT did not fully substitute for any of the training drugs, but produced 67% LSD-appropriate responding. None of the compounds produced substitution in rats trained to discriminate cocaine or methamphetamine. All three compounds showed activity at 5-HT1A and 5-HT2A receptors as well as blockade of reuptake by the serotonin transporter. In addition, 5-MeO-AMT produced low levels of serotonin release and low potency blockade of dopamine uptake. DIPT, 5-MeO-DET, and 5-MeO-AMT produced behavioral and receptor effects similar to those of abused hallucinogens, but were not similar to those of psychostimulants. DIPT and 5-MeO-DET may have abuse liability similar to known hallucinogens and may be hazardous as high doses produced activity and lethality.
- Received January 20, 2011.
- Revision received April 5, 2011.
- Accepted April 6, 2011.
- The American Society for Pharmacology and Experimental Therapeutics