Effects of ethanol on tryptophan hydroxylase activity from striate synaptosomes

Michael A Rogawski, Suzanne Knapp, Arnold J. Mandell

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Ethanol inhibits the conversion of tryptophan to serotonin (5-HT) by rat striate synaptosomes in vitro in concentrations as low as 0.1 M. This effect is apparently not mediated by a decrease in the uptake of radioactive tryptophan but through a noncompetitive inhibition of the activity of the enzyme tryptophan-5-hydroxylase (EC 1.99.1.4) itself. Experiments showing: (1) a correlation between the inhibitory potencies of a number of alcohols of increasing carbon chain length and their partition coefficients, and (2) a calculable increment of binding of 0.47 kcal/mole/methylene unit in the alcohol series (which should be between 036 and 0.95 kcal/mole if the methylene unit is the source of ΔF) suggest that the inhibition may operate via a hydrophobic site on the enzyme.

Original languageEnglish (US)
Pages (from-to)1955-1962
Number of pages8
JournalBiochemical Pharmacology
Volume23
Issue number14
DOIs
StatePublished - Jul 15 1974

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Tryptophan Hydroxylase
Synaptosomes
Tryptophan
Serotonin
Ethanol
Alcohols
Enzymes
Carbon
Mixed Function Oxygenases
Chain length
Rats
Experiments
In Vitro Techniques

ASJC Scopus subject areas

  • Pharmacology

Cite this

Effects of ethanol on tryptophan hydroxylase activity from striate synaptosomes. / Rogawski, Michael A; Knapp, Suzanne; Mandell, Arnold J.

In: Biochemical Pharmacology, Vol. 23, No. 14, 15.07.1974, p. 1955-1962.

Research output: Contribution to journalArticle

Rogawski, Michael A ; Knapp, Suzanne ; Mandell, Arnold J. / Effects of ethanol on tryptophan hydroxylase activity from striate synaptosomes. In: Biochemical Pharmacology. 1974 ; Vol. 23, No. 14. pp. 1955-1962.
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