4-HO-TMT
4-HO-TMT, or 4-OH-TMT, also known as 4-hydroxy-N,''N,N''-trimethyltryptammonium or as dephosphorylated aeruginascin, is a substituted tryptamine derivative and the active form of aeruginascin, analogously to how psilocin is the active form of psilocybin. 4-HO-TMT is closely related to bufotenidine, the N-trimethyl analogue of serotonin.
Use and effects
Pharmacology
Like psilocin, 4-HO-TMT shows affinity for the serotonin 5-HT1A, 5-HT2A, and 5-HT2B receptors. However, its affinities for these receptors are lower than those of psilocin. Additionally, in another study, the value of 4-HO-TMT in activating the serotonin 5-HT2A receptor was 324-fold lower than that of psilocin. Similarly to psilocin, 4-HO-TMT does not bind to the serotonin 5-HT3 receptor. This was in contrast to predictions, as the related compound bufotenidine is a strong and selective serotonin 5-HT3 receptor agonist.4-HO-TMT is a quaternary trimethyl ammonium compound, and as a result, is less likely to be able to cross the blood–brain barrier and enter the central nervous system than other tryptamines. Accordingly, 4-HO-TMT showed no ability to cross an artificial BBB-like membrane in a study. In rodents, 4-HO-TMT showed no head-twitch response, hypolocomotion, or hypothermia, in contrast to psilocin and norpsilocin, but similarly to aeruginascin.