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PubMed · 7441237

Tyrosine loading enhances catecholamine excretion by rats.

R Alonso·J C Agharanya·R J Wurtman
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Abstract

Tyrosine administration to rats causes dose-related increases in urinary catecholamine levels without reducing tissue catecholamines. Pretreatment with carbidopa, a peripheral inhibitor of aromatic-L-amino acid decarboxylase, reduces basal urinary catecholamine levels and blocks of urinary catecholamine increases caused by tyrosine administration or cold exposure. DOPA excretion, which is usually undetectable by our methods, becomes significant after carbidopa, and rises a further four-fold when rats are also given tyrosine. These observations suggest that tyrosine availability can affect both catecholamine synthesis in and release from the sympathoadrenal apparatus.

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Adrenal GlandsAnimalsCarbidopaCatecholaminesCold TemperatureDose-Response Relationship, DrugEpinephrineMaleMyocardiumNorepinephrineRatsTyrosineJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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R Alonso, J C Agharanya, R J Wurtman. 1980. Tyrosine loading enhances catecholamine excretion by rats.. https://doi.org/10.1007/bf01249187

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