A comparison of N,N-dimethyltryptamine, harmaline, and selected congeners in rats trained with LSD as a discriminative stimulus
Progress in Neuro-Psychopharmacology and Biological Psychiatry May 1, 1998 Scott Helsley, David Fiorella, Richard A. Rabin et al. 30 citations
In rats trained to distinguish LSD from saline, several N-substituted tryptamines produced intermediate levels of LSD-like responding: MDMT (76.4%), DMT (77.9%), and DET (48.7%). 6-F-DET elicited 41.3% LSD-appropriate responding at 6.0 mg/kg, but only 4 of 8 subjects completed the session, precluding statistical analysis. Bufotenine (25.8%) failed to substitute. None of the tryptamines substituted completely for LSD, though the pattern aligns with their known human hallucinogenic activity. Among beta-carbolines tested, only harmane showed intermediate substitution (49.5%); others, including harmaline and THBC, showed no significant generalization. The tryptamines overall showed greater similarity to the LSD stimulus than the beta-carbolines did.