A pilot study of cerebral metabolism and serotonin 5-HT2A receptor occupancy in rats treated with the psychedelic tryptamine DMT in conjunction with the MAO inhibitor harmine.
Frontiers in pharmacology January 1, 2023 Klemens Egger, Frederik Gudmundsen, Naja Støckel Jessen et al. 17 citations
Co-administration of harmine with DMT in rats increased brain DMT levels by inhibiting its metabolism to indole-3-acetic acid, yet no significant occupancy of serotonin 5-HT2A receptors by DMT was detected, even at brain DMT concentrations up to 11.3 µM. Low doses of DMT and/or harmine did not significantly alter brain glucose metabolism as measured by [18F]FDG-PET. These preliminary findings suggest that the role of MAO-A inhibition in potentiating DMT's psychedelic effects may be more complex than previously assumed, and further dose-response studies are needed.