Possible Interaction: Ethanol and Tryptophan

“ Lowered tryptophan levels and ingestion of alcohol were associated with increased aggression.”

“Two important findings have been made recently: (1) subsets of individuals (e.g., persons self-rating high on aggressive or hostility scales) may differ in their susceptibility to aggression produced through plasma tryptophan depletion; and (2) alcohol in combination with L-tryptophan depletion has an additive effect on aggression.”

“ Alcohol has been found to mimic the effects of tryptophan or serotonin.”

“ Alcohol (ethanol) exerts a variety of effects on tryptophan (Trp) and 5-hydroxytryptamine (5-HT, serotonin) metabolism in man and experimental animals.”

“Levels of tryptophan in brain are increased by the action of chronic ethanol , particularly in the event of compromised hepatic function.”

“Single administration of ethanol in doses of 3 and 5 g/kg per os caused a 4--5fold increase in plasma 11-hydroxycorticosteroids after one hour and an approximately 2 fold increase in liver tryptophan pyrrolase activity after 5 hours.”

“We therefore tested whether dietary tryptophan TRP ) enhancement would modulate stress-induced desire for alcohol and whether it would affect the two populations (BD/NBD) differently.”

“AIMS We have previously suggested that acute ethanol consumption by normal subjects decreases the availability of circulating tryptophan (Trp) to the brain by activating liver Trp pyrrolase, the first and rate-limiting enzyme of the (major) kynurenine pathway of Trp degradation.”

“They argue that this occurs because chronic ethanol intake inhibits synthesis of hepatic tryptophan oxygenase (TPO), the major quantitative catabolic enzyme for Trp metabolism (Young et al. 1978).”

“High pressures (120 and 240 MPa) and added ethanol resulted in change in casein hydrophobicity by exposure of tryptophan residues , as confirmed by spectroscopic methods.”