Tryptamine derivatives and beta-Carbolines have been detected as endogenous metabolites in mammals, including humans. Methyl transferases that catalyze the synthesis of tryptamines, including DMT, 5-MeO-DMT and bufotenine, are found in human lung, brain, cerebrospinal fluid, liver and heart (McKenna & Towers 1984). In the pineal gland MAO is the primary inactivation pathway of serotonin, a neurotransmitter synthesized from the amino acid tryptophan. If MAO is blocked by harmine, harmaline or other MAO inhibitors serotonin can be converted by the methyltransferase enzymes HIOMT and INMT into psychedelic tryptamines (serotonin --(HIOMT)--> 5-MeO-trypt. --(2*INMT)--> 5-MeO-DMT). So, ingesting l-tryptophan to increase serotonin levels, a candy bar to increase the amount of tryptophan getting to your brain and natural plant material containing 25-50 mg harmine/harmaline to block MAO, all at the same time, might cause your pineal gland to synthesize substantial amounts of 5-MeO-DMT (Most 1986). Similar results might be obtained by substituting 5-hydroxytryptophan (5-HTP) for tryptophan. Normal sleep-inducing doses of melatonin have also been taken with reversible MAOIs with the resulting psychoactive effects suggesting significant interaction of the two substances. This is extremely dangerous for persons with existing amine imbalance or schizophrenia. For normal, healthy people possible consequences are bad.
A potent inhibitor of INMT, which is a necessary enzyme for the synthesis of DMT and 5-MeO-DMT, is found in particularly high concentrations in the pineal gland. A bypassing or inhibition of the synthesis of this inhibitor might be responsible for trances and other psychedelic states achieved "without drugs" (Strassman 1990). See Strassman's article for more info and speculation about the pineal gland.
