Function of Catecholamines in the Brain During Depression
|First Received Date ICMJE||April 28, 2004|
|Last Updated Date||December 1, 2011|
|Start Date ICMJE||April 2004|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT00082030 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Function of Catecholamines in the Brain During Depression|
|Official Title ICMJE||Neural Correlates of Depressive Symptoms and Reward Related Mechanisms Following AMPT Depletion in Remitted Depressed Patients Off Treatment and Healthy Controls|
This study will explore brain function related to depressive symptoms and will examine DNA for genes that may be involved in depressive disorders, particularly genes that regulate synthesis and metabolism of the brain neurotransmitter catecholamine. It will compare findings in patients with major depressive disorders who are in remission with those in normal, healthy volunteers.
Patients with remitted major depressive disorders and healthy normal volunteers between 18 and 60 years of age may be eligible for this study. Candidates are screened with a psychiatric and medical history, physical examination, electrocardiogram, and blood and urine tests. Participants undergo the following tests and procedures in up to eight visits to the NIH Clinical Center:
Memory Tasks and Problem Solving and Brain Imaging
Subjects are tested with measurements of intelligence or memory ability. They also undergo magnetic resonance imaging (MRI), a test that uses a magnetic field and radio waves to produce images of the brain. For this procedure, the patient lies on a table that is moved into the scanner (a narrow cylinder), and wears earplugs to muffle loud knocking and thumping sounds that occur during the scanning process. The MRI lasts about 60 minutes.
Catecholamine Depletion Study
For this study, subjects take capsules containing either AMPT (a drug that temporarily reduces brain catecholamine activity) or a placebo (lactose capsules, which do not affect brain catecholamine activity) at 9 a.m., 2 p.m., and 7 p.m. on one visit and return the next day to take additional capsules at 7 a.m. and noon. In addition to the study medication, subjects keep a low-monoamine diet (e.g., no chocolate, cheese, smoked meats, and various other foods that will be enumerated) and do not smoke, drink alcohol, or take in food or drink containing caffeine. After taking all the study capsules, the subjects have positron emission tomography (PET) and functional MRI (fMRI) scans, as follows:
The catecholamine depletion study is repeated a second time 14 days or more after the first. Subjects who received AMPT capsules for the first study take lactose capsules for the second study, and vice-versa.
The depressive and anhedonic response precipitated by CD raises the possibility that dysfunction of the dopamine system is a stable, sometimes latent characteristic of MDD. Following this line of reasoning, central catecholamine dysfunction as evinced by CD may be equally salient in a subset of unaffected relatives who are at genetic risk for developing the disorder.
We plan to extend the phase I project to unaffected relatives of BD and MDD patients in order to evaluate sensitivity to CD as an endophenotype of MDD and BD. In order to maximize our statistical power, we will be recruiting equal numbers healthy low and high-risk relatives. Here, risk is defined on the basis of chronological age (see below for more detail).
Furthermore, it has recently become feasible to conduct genome-wide association studies and quantify the burden of risk alleles carried by an individual. Certainly, the identity of these risk alleles remains unknown or unproven. Nevertheless, Francis McMahon's group, with whom we are collaborating, have identified upwards of 20 common risk variants in two independent samples. Individuals carrying 19 or more of these risk alleles were found to be 4 times more likely to be cases than controls. This approach may provide us with another method of quantifying genetic risk.
The endophenotypic status of sensitivity to CD will be evaluated with psychometric instruments, FDG PET, and an fMRI-coupled appetitive learning task. We now have access to a high resolution PET scanner (High Resolution Research Tomograph) that will enable us to study hitherto irresolvable structures of importance such as the habenula and peri-aqueductal gray matter (PAG) in addition to previously implicated regions such as the ventral striatum and OFC. Analysis of the metabolic activity of these regions under sham and CD conditions in both remitted MDD and relatives of BD and MDD patients is of great theoretical import. So to is identifying regions of the brain involved in reward response that are selectively impacted by CD, a question that we hope to answer through the use of the fMRI-coupled appetitive learning task.
|Study Type ICMJE||Observational|
|Study Design ICMJE||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Completion Date||November 2011|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
MDD Sample: 40 subjects (ages 18-45) with remitted MDD will be selected. MDD is defined by the DSM-IV criteria, and one of the following additional criteria:
Unaffected MDD Relative Sample:
40 healthy relatives of MDD probands (ages 18-45) will be recruited. Subjects will be screened to ensure that they have no history of psychiatric illness.
Unaffected BD Relative Sample:
Healthy relatives of BD probands (ages 18-45) will be recruited. Subjects will be screened to ensure that they have no history of psychiatric illness.
Healthy Control Samples:
-Healthy subjects (ages 18-45) without a known personal or first-degree family history of psychiatric disorders in first-degree relatives will be selected.
|Ages||18 Years to 45 Years|
|Accepts Healthy Volunteers||Yes|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||United States|
|NCT Number ICMJE||NCT00082030|
|Other Study ID Numbers ICMJE||040160, 04-M-0160|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Institute of Mental Health (NIMH)|
|Collaborators ICMJE||Not Provided|
|Investigators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||November 2011|
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