Possible Interaction: Epinephrine and Tryptophan

“ Tryptophan infusion resulted in a marked increase in epinephrine (Premean = 23.92 (12.23) versus Postmean = 81.57 (62.36)) and decrease in norepinephrine (Premean = 257.2 (106.11) versus Postmean = 177.04 (87.15)), whereas levels of both catecholamines were stable on the “sham day.””

“Norepinephrine and epinephrine , and to a lesser extent histamine, also increased W and decreased SWS and PS, whereas serotonin, dopamine and carbachol, a cholinergic agonist, had no effect.”

“SH rats, treated with the higher dose of tryptophan , also significantly reduced their urinary outputs of epinephrine and norepinephrine compared with SH controls, while both doses of tryptophan increased urinary outputs of dopamine significantly above that of SH controls.”

“While adrenal ablation produced significant decreases in the brain serotonin and metabolite concentrations and marked increases in brain tryptophan concentrations for both diet groups compared to their respective controls, these substances remained significant higher in all malnourished rats than in the well-nourished groups.”

“The administration of L-tryptophan prevented the normal rise in blood sugar concentration that usually follows the injection of epinephrine into rats.”

“ Tryptophan depletion increased both epinephrine and norepinephrine levelswhereas tryptophan enhancement increased epinephrine and decreased norepinephrine.”