Dissociation of the effects of epinephrine and insulin on glucose and protein metabolism

Journal Article · Mon Jan 01 04:00:00 EST 1990 · American Journal of Physiology; (USA)

OSTI ID:7191480

Castellino, P; Luzi, L; Del Prato, S; DeFronzo, R A ^[1]

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1. Univ. of Texas Health Science Center, San Antonio (USA)

The separate and combined effects of insulin and epinephrine on leucine metabolism were examined in healthy young volunteers. Subjects participated in four experimental protocols: (1) euglycemic insulin clamp (+80 microU/ml), (2) epinephrine infusion (50 ng.kg-1.min-1) plus somatostatin with basal replacement of insulin and glucagon, (3) combined epinephrine (50 ng.kg-1.min-1) plus insulin (+80 microU/ml) infusion, and (4) epinephrine and somatostatin as in study 2 plus basal amino acid replacement. Studies were performed with a prime-continuous infusion of (1-14C)leucine and indirect calorimetry. Our results indicate that (1) hyperinsulinemia causes a generalized decrease in plasma amino acid concentrations, including leucine; (2) the reduction in plasma leucine concentration is primarily due to an inhibition of endogenous leucine flux; nonoxidative leucine disposal decreases after insulin infusion; (3) epinephrine, without change in plasma insulin concentration, reduces plasma amino acid levels; (4) combined epinephrine-insulin infusion causes a greater decrease in plasma amino levels than observed with either hormone alone; this is because of a greater inhibition of endogenous leucine flux; and (5) when basal amino acid concentrations are maintained constant with a balanced amino acid infusion, epinephrine inhibits the endogenous leucine flux. In conclusion, the present results do not provide support for the concept that epinephrine is a catabolic hormone with respect to amino acid-protein metabolism. In contrast, epinephrine markedly inhibits insulin-mediated glucose metabolism.

• OSTI ID: 7191480
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 258; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ADRENALINE
AMINO ACIDS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOCHEMICAL REACTION KINETICS
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
CARDIOTONICS
CARDIOVASCULAR AGENTS
DRUGS
HORMONES
INHIBITION
INSULIN
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LEUCINE
METABOLISM
NEUROREGULATORS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PEPTIDE HORMONES
REACTION KINETICS
RESPIRATION
SYMPATHOMIMETICS
TRACER TECHNIQUES