Possible Interaction: Caffeine and Tryptophan

“ Caffeine significantly increased the duration of W and decreased the duration of SWS and REMS compared to the Control.”

“ Caffeine injected at doses of 20, 40 and 80 mg/kg increased brain levels of tryptophan , 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) in rat brain.”

“Caffeine-induced increases of brain tryptophan but not 5-HT and 5-HIAA were greater in 5 day caffeine than 5 day saline injected rats.”

“In adrenalectomized animals the induction of the tyrosine aminotransferase by tryptophan is markedly elevated by caffeine and theophylline.”

“ Acute caffeine injection (100 mg/kg) elevates brain levels of tryptophan ( TRP ), serotonin (5HT), and 5-hydroxyindoleacetic acid (5HIAA).”

“ Caffeine thus probably raises brain tryptophan levels by causing insulin secretion, and thereby changing plasma amino acid levels to favor increased tryptophan uptake into brain.”

“The result indicated that caffeine can change the conformation of the protein, leading to the change in the micro-environment of tryptophane and tyrosine residues from hydrophobic environment to hydrophilic environment to different extent.”

“ Caffeine interacted with L-tryptophan at a molar ratio of 1:1 by parallel stacking.”

“From measurements at several temperatures the heat of binding of tryptophan with caffeine was shown to be −4.0 kcal./mole and that with theophylline to be −4.2 kcal./mole.”