Protocol Number: 05-M-0035
Healthy volunteers and patients with major depression that has been in remission for at least 3 months may be eligible for this study. Candidates must be between 18 and 50 years of age and right-handed. They are interviewed about their medical and psychiatric history, current emotional state and sleep pattern, and family history of psychiatric disorders. Screening also includes psychiatric interviews and rating scales, neuropsychological tests, physical examination, electrocardiogram (EKG), and blood, urine, and saliva tests. Women have their menstrual phase determined by a blood test and home urine ovulation test kit. The study involves two clinic visits in which participants undergo tryptophan depletion and magnetic resonance imaging (MRI). Subjects arrive at the NIH Clinical Center in the morning after fasting overnight. They fill out questionnaires have a blood sample drawn, and then take 74 capsules that contain a mixture of amino acids found in the diet. At one visit they are given capsules that contain a balanced mixture of amino acids one would normally eat in a day; at the other visit, some of the capsules contain lactose instead of tryptophan, causing tryptophan depletion. At 2 p.m. participants fill out the same questionnaires they completed at the beginning of the day and have another blood sample drawn. Then they do a computerized test in the MRI scanner. MRI uses a magnet and radio waves to obtain pictures of the brain. For the test, subjects lie on a narrow bed that slides into the cylindrical MRI scanner. They are asked to press a button in response to words associated with different emotions that appear on a screen. Arterial spin labeling - a test that uses magnetism to measure blood flow in different areas of the brain-is also done during the procedure. After the scan, subjects eat a meal and then return home. DNA from the participants' blood samples is also examined to try to better understand the genetic causes of depression. Some of the white cells from the samples may also be grown in the laboratory so that additional studies can be done later.
Search The Studies | Help | Questions |
National Institutes of Health Clinical Center
Bethesda, Maryland 20892. Last update: 01/30/2009
|
||