| 摘要 |
<p>The level of a catecholamine in neuronal synapses is increased in order to improve vigor by administering a neutral amino acid composition to a human wherein an increased brain level of a catecholamine is effected when the composition contains increased amounts of tyrosine and/ or phenylalanine. Increased or decreased brain levels of serotonin are obtained when the amino acid composition contains increased or decreased amounts of tryptophan. The neutral amino acid composition can be administered alone or concomitantly with a drug which increases or decreases catecholaminergic neurotransmission. </p> |
