Accession Number : ADP005657

Title :   Use of Tyrosine and Other Nutrients to Enhance and Sustain Performance,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF BRAIN AND COGNITIVE SCIENCES

Personal Author(s) : Wurtman, Richard J.

Report Date : MAR 1987

Pagination or Media Count : 4

Abstract : ADMINISTRATION OF SUPPLEMENTAL TYROSINE CAN INCREASE THE RELEASE OF THE CATECHOLAMINES DOPAMINE, NOREPINEPHRINE, AND EPINEPHRINE FROM PHYSIOLOGICALLY-ACTIVE NEURONS, AND CAN THEREBY MODIFY BEHAVIORS AND OTHER NEURONAL FUNCTIONS (E.G., CONTROL OF BLOOD PRESSURE; NEUROENDOCRINE SECRETION) THAT ARE MEDIATED BY THESE NEUROTRANSMITTERS. The tyrosine acts by increasing the substrate-saturation of the enzyme becomes phosphorylated and, consequently, tyrosine-dependent. The amount of tyrosine that enters the brain varies with the plasma tyrosine ratio, i.e., the ratio of the plasma tyrosine concentration to the summed concentrations of other large neutral amino acids that compete with tyrosine for transport across the blood-brain barrier. Hence, the administration of pure tyrosine is much more effective than eating proteins, which contain tyrosine: the proteins contain-and deliver to the blood stream-considerably larger amounts of the other large neutral amino acids. Tyrosine administration protects rats from the neurochemical and behavioral effects of stress; its ability to enhance performance of stressed humans is under exploration.

Descriptors :   *PERFORMANCE(HUMAN), *TYROSINE, DRUGS, CNS STIMULANTS, CATECHOLAMINES, NERVE TRANSMISSION, DOPAMINE, NUTRITION, METABOLISM, EPINEPHRINE, ENZYMES.

Subject Categories : Psychology
      Pharmacology

Distribution Statement : APPROVED FOR PUBLIC RELEASE