Possible Interaction: Tranylcypromine and Tryptophan

“Four patients developed a distinctive neuromotor syndrome following TRP during tranylcypromine , but not placebo, treatment.”

“ Tranylcypromine significantly increased the prolactin response to TRP.”

“Stereotyped hyperactivity in rats following combined administration of tranylcypromine , a monoamine oxidase (MAO) inhibitor, and tryptophan has been attributed to an extraneuronal excess of 5-hydroxytryptamine (5-HT).”

“Both hyperactivity and the behavioural syndrome seen after tranylcypromine (20 mg/kg) followed byl-tryptophan (100 mg/kg) were decreased by prior treatment with CBZ (14 days).”

“A comparison of the behavioural effects of tranylcypromine plus l-tryptophan (50 and 100 mg/kg) showed a small increase in locomotor activity and a greater increase in the behavioural score with the higher dose.”

“Rats pretreated with the monoamine oxidase inhibitor tranylcypromine and given l-tryptophan develop a characteristic behavioural syndrome.”

“Brain 5-HT concentration in the rat was elevated by combined treatment with tranylcypromine and L-tryptophan , tranylcypromine alone, by a single dose of the 5-HT releasing agent p-chloroamphetamine (PCA) or by the selective 5-HT reuptake inhibitor paroxetine.”

“Two hours after the combined administration of tranylcypromine and L-tryptophan BDNF mRNA abundance in the dentate gyrus was significantly decreased but increased in the frontal cortex.”

“Valofan (250 and 500 mg/kg) always reduced spontaneous locomotion and amphetamine-induced hypermotility; after the administration of L-tryptophan (10 mg/kg) and tranylcypromine (1 mg/kg) both locomotions decreased; when administered in combination with valofan they resulted in an additive effect.”

“Inhibition of AGS by tryptophan was potentiated by combination with either of the mixed MAO inhibitors nialamide or tranylcypromine.”

“The appearance of head weaving, forepaw treading and hind-limb abduction, which followed the administration of tranylcypromine (5 mg/kg) plus L-tryptophan (100 mg/kg) or quipazine (50 mg/kg) to rats, was also inhibited by pretreatment with pirenperone (100 micrograms/kg).”

“The increase in brain tryptophan concentration caused by administration of mianserin, viloxazine, desipramine or tranylcypromine is associated with an accumulation of tryptophan in the liver and an increased availability of the circulating amino acid to the brain.”

“Administration to rats of a monoamine oxidase inhibitor (for example tranylcypromine : Tcp) followed by L-tryptophan increases the rate of synthesis and release of 5-hydroxytryptamine (5-HT) and results in a series of behavioural changes, some of which can be recorded on activity meters or scored.”