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NCT00033787 · ClinicalTrials.gov registry record
Serotonin Function During Depression
A clinical trial, sponsored by National Institute of Mental Health (NIMH).
- Completed
- Registry status
- 450
- Enrollment target
NCT00033787: Completed study, sponsored by National Institute of Mental Health (NIMH).
NCT00033787 is a clinical trial that has completed, run by National Institute of Mental Health (NIMH). The registered enrollment target is 450 participants. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00033787 has completed, sponsored by National Institute of Mental Health (NIMH).
- COMPLETED
- Registry status
- 450 participants
- Enrollment target
Study Summary
Serotonin is a chemical involved in regulation of emotions, anxiety, sleep, stress hormones, and other body functions. The purpose of this study is to use a procedure called tryptophan depletion to study the function of serotonin in people with depression and in healthy volunteers. Major depressive disorder (MDD) has been associated with reduced functioning of central serotonergic systems. Tryptophan depletion (TD) is a procedure used to investigate the relationship between serotonergic function and depression. Evidence suggests that the mood lowering effects of TD depend upon family history and differences in genes for a specific protein called 5-HTTLPR. Healthy females with a particular gene for 5-HTTLPR and a family history of mood disorders appear to be at a greater risk for the development of depressive symptoms during TD. This study will use positron emission tomography (PET) scans of the brain to investigate the effect of variant 5-HTTLPR genotypes on response to TD. The relationship between 5-HTTLPR genotypes and the effect of TD on brain activity in individuals with different 5-HTTLPR genes will be determined. This study will also examine how the reduced serotonin function that occurs in MDD affects the brain's response to sensory stimulation. Participants in this study will be screened by telephone about their psychiatric and medical history, current emotional state, anxiety and sleep patterns, and family history of psychiatric disorders. At study entry, participants will have an interview, physical examination, electrocardiogram (EKG), and blood and laboratory tests. Menstruating women will have a pregnancy test and tests to determine menstrual phase and time of ovulation. At the second clinic visit, participants will undergo tests of intelligence and cognitive abilities and a magnetic resonance imaging (MRI) scan of the brain. Prior to Visits 3 and 4, participants will collect their saliva and urine. Menstruating women will have a pregnancy test. At Vi
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 450 participants |
| Start Date | 2002-04-05 |
| Est. Completion | 2005-04-30 |
What the finished NCT00033787 record still lists
NCT00033787 is an observational study that tracks outcomes without assigning an intervention. The registered 450 participants enrollment target is mid-sized for trials with a published cap.
The record links to 0 conditions, and to 0 interventions.
NCT00033787 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00033787 about?
NCT00033787 is a clinical study titled "Serotonin Function During Depression". Serotonin is a chemical involved in regulation of emotions, anxiety, sleep, stress hormones, and other body functions. The purpose of this study is to use a procedure called tryptophan depletion to study the function of serotonin in people with depression and in healthy volunteers. Major depressive...
What is the current status of trial NCT00033787?
This trial is currently completed. The enrollment target is 450 participants. The study started on 2002-04-05. Estimated completion is 2005-04-30.
Who is sponsoring clinical trial NCT00033787?
This trial is sponsored by National Institute of Mental Health (NIMH), which has 343 total clinical trials registered on ClinicalTrials.gov.
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