Injected tryptophan increases brain but not plasma tryptophan levels more in ethanol treated rats

Journal Article · Mon Jan 01 04:00:00 EST 1990 · Life Sciences; (USA)

DOI:https://doi.org/10.1016/0024-3205(90)90544-2· OSTI ID:6034776

Haleem, D J ^[1]

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1. Univ. of Karachi (Pakistan)

In the present study ethanol treatment given for two weeks decreased hepatic apo-tryptophan pyrrolase but not total tryptophan pyrrolase activity in rats. Tryptophan levels in plasma and brain did not increase significantly. But there was a marked increase of 5-HT but not 5-hydroxyindoleacetic acid (5-HIAA) concentration in brain, suggesting a possible increase in the activity of tryptophan hydroxylase. The effect of a tryptophan load on brain 5-HT metabolism was therefore compared in controls and ethanol treated rats. One hour after tryptophan injection plasma concentrations of total and free tryptophan were identical in controls and ethanol treated rats, but the increases of brain tryptophan 5-HT and 5-HIAA were considerably greater in the latter group. The results are consistent with long term ethanol treatment enhancing brain serotonin metabolism and show that brain uptake/utilization of exogenous tryptophan is increased in ethanol treated rats and may be useful to understand the role and possible mechanism of tryptophan/serotonin involvement in mood regulation.

• OSTI ID: 6034776
• Journal Information: Life Sciences; (USA), Journal Name: Life Sciences; (USA) Vol. 47:11; ISSN 0024-3205; ISSN LIFSA
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALCOHOLS
AMINES
AMINO ACIDS
ANIMALS
AROMATICS
AUTONOMIC NERVOUS SYSTEM AGENTS
AZAARENES
AZOLES
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BIOSYNTHESIS
BLOOD
BLOOD PLASMA
BODY
BODY FLUIDS
BRAIN
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM
DRUGS
ENZYME ACTIVITY
ENZYMES
ETHANOL
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROLASES
HYDROXY COMPOUNDS
INDOLES
MAMMALS
MATERIALS
METABOLISM
NERVOUS SYSTEM
NEUROREGULATORS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PYRROLES
RADIOPROTECTIVE SUBSTANCES
RATS
RODENTS
SEROTONIN
SYMPATHOMIMETICS
SYNTHESIS
TRYPTAMINES
TRYPTOPHAN
VERTEBRATES