Discriminative stimulus effects of N,N-diisopropyltryptamine.

The hallucinogen DiPT, known for causing auditory distortions, produces discriminative stimulus effects in rats that are similar to those of other synthetic hallucinogens like LSD, DOM, and MDMA, but only partially similar to DMT and not similar to methamphetamine. Rats learned to distinguish DiPT from saline in about 60 training sessions. DiPT caused dose-dependent increases in drug-appropriate responding, reaching 99% at the highest dose. The effects began within 5 minutes and faded within 4 hours. The results suggest that DiPT's auditory effects do not make its discriminative stimulus profile distinct from other hallucinogens.

Study at a glance

Abstract

Serotonergic hallucinogens such as (+)-lysergic acid diethylamide (LSD) and dimethyltryptamine (DMT) produce distinctive visual effects, whereas the synthetic hallucinogen N,N-diisopropyltryptamine (DiPT) is known for its production of auditory distortions. This study compares the discriminative stimulus effects of DiPT to those of visual hallucinogens. Adult male rats were trained to discriminate DiPT (5 mg/kg, 15 min) from saline under a FR10 schedule. A dose-effect and time course of DiPT's discriminative stimulus effects were established. DMT, (-)-2,5-dimethoxy-4-methylamphetamine (DOM), LSD, (±)-methylenedioxymethamphetamine (MDMA), and (+)-methamphetamine were tested for cross-substitution in DiPT-trained animals. Rats learned to discriminate DiPT from saline in an average of 60 training sessions (30 drug and 30 saline). DiPT (0.5-5 mg/kg) produced dose-dependent increases in drug-appropriate responding (DAR) to 99 % (ED(50) = 2.47 mg/kg). Onset of the discriminative stimulus effects was within 5 min, and the effects dissipated within 4 h. Full substitution for the discriminative stimulus effects of DiPT occurred with LSD, DOM, and MDMA. DMT only partially substituted for DiPT (65 % DAR), whereas (+)-methamphetamine failed to substitute for DiPT (29 % DAR). The discriminative stimulus effects of DiPT were similar those of a number of synthetic hallucinogens, only partially similar to those of DMT, but not similar to (+)-methamphetamine. The putative DiPT-induced auditory distortions do not lead to discriminative stimulus effects distinguishable from other hallucinogens.