Examining serotonin function

A modified technique for rapid tryptophan depletion

Lois Elaine Krahn, Peter Y. Lu, George Klee, Pedro R. Delgado, Slong Chi Lin, Ralf C. Zimmermann

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

Tryptophan (TRP) depletion was used to study serotonin because the ratio of TRP to large neutral amino acids (TRP/LNAA) determines the quantity of TRP that enters the brain. Because TRP is not universally available, a modified technique of TRP depletion was developed where a 1/4 strength preparation of an amino acid mixture (AAM) replaces TRP as the placebo. Seven healthy subjects could not differentiate between the preparations in this double-blind, placebo-controlled study. Urinary hydroxymelatonin sulfate (6-MS) was monitored as a biochemical marker of serotonin. The TRP/LNAA ratio (GG = 0.0001) and 6-MS secretion (GG = 0.024) were decreased, but placebo TRP levels (GG = 0.062) were not altered significantly. This modified technique facilitates the use of TRP depletion in clinical research.

Original languageEnglish (US)
Pages (from-to)325-328
Number of pages4
JournalNeuropsychopharmacology
Volume15
Issue number4
DOIs
StatePublished - Oct 1996

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Tryptophan
Serotonin
Placebos
Neutral Amino Acids
Sulfates
Healthy Volunteers
Biomarkers
Amino Acids
Brain
Research

Keywords

  • Competing amino acids
  • Melatonin
  • Mood
  • Serotonin
  • Tryptophan

ASJC Scopus subject areas

  • Pharmacology

Cite this

Examining serotonin function : A modified technique for rapid tryptophan depletion. / Krahn, Lois Elaine; Lu, Peter Y.; Klee, George; Delgado, Pedro R.; Lin, Slong Chi; Zimmermann, Ralf C.

In: Neuropsychopharmacology, Vol. 15, No. 4, 10.1996, p. 325-328.

Research output: Contribution to journalArticle

Krahn, Lois Elaine ; Lu, Peter Y. ; Klee, George ; Delgado, Pedro R. ; Lin, Slong Chi ; Zimmermann, Ralf C. / Examining serotonin function : A modified technique for rapid tryptophan depletion. In: Neuropsychopharmacology. 1996 ; Vol. 15, No. 4. pp. 325-328.
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