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Radiosynthesis of 1-2-[18F]Fluoroethyl-L-Tryptophan using a One-pot, Two-step Protocol
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Can formulation affect tryptophan depletion results? Hints from studies in experimental panic
Sjacko Sobczak1, Koen Schruers
11Mondriaan Department of Old Age Psychiatry/Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, The Netherlands.
Journal of Psychopharmacology (Oxford, England)
|January 17, 2014
Summary
Acute Tryptophan Depletion (ATD) may enhance fear in panic disorder patients. Methodological differences, particularly ATD mixtures, might explain varied outcomes in fear research.
Area of Science:
- Neuroscience
- Psychopharmacology
- Clinical Psychology
Background:
- Acute Tryptophan Depletion (ATD) is a tool to challenge the serotonin system.
- The central serotonergic effects of ATD procedures may differ from assumptions.
Purpose of the Study:
- Review ATD data in an experimental fear model.
- Investigate how methodological differences impact fear outcomes.
- Test hypotheses regarding discrepancies in laboratory studies.
Main Methods:
- Literature search of PubMed and MEDLINE.
- Comparison of studies conducted in the authors' laboratory.
- Analysis of methodological variations, specifically ATD mixtures.
Main Results:
- Eight studies were reviewed (5 in panic disorder patients, 3 in healthy individuals).
- Studies in the authors' laboratory were methodologically similar, differing mainly in ATD mixtures.
- ATD appears to enhance fear in panic disorder patients more than in healthy individuals.
Conclusions:
- Findings on ATD's fear-enhancing effects are inconclusive.
- Discrepancies in laboratory findings may stem from variations in ATD mixtures.
- Potential mechanisms involve ATD mixtures affecting central tryptophan and serotonin availability.
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