it appears that the ability of the brain 's neurons to make and release several neurotransmitters ( serotonin , acetylcholine , and probably the catecholamines dopamine and norepinephrine ) depends directly on the concentration of amino acids and choline in the blood , and quite possibly on the composition of the most recently digested meal .
C0007412
catecholamines
C0028351
norepinephrine