Eligibility Procedures: Before entering the study and prior to any other procedures, you will be asked to read and sign this consent form. To determine if you are eligible for our study, you will then have a general medical (including menstrual cycle history on female patients) and psychiatric history taken, a physical examination your vital signs (blood pressure, pulse), height, weight, waist/hip ratio will be measured, and various psychiatric evaluations will be conducted. We will be video recording the psychiatric diagnostic assessment of every 5th patient who enrolls in our study.
On Day 1, your mood will be evaluated using a series of commonly used diagnostic instruments and rating scales. We will repeat the medical exam, blood and urine lab tests you had at your initial screening visit if it has been more than 4 weeks (30 days) since your eligibility screening.
The rest of the study includes an MRI, neuropsychological testing, questionnaires, and blood draws.
The MRI (called magnetic resonance imaging, MRI) involves having a picture of your brain taken using a magnet while a series of tasks is administered to you. The MRI scan procedures will take approximately 1 hour.
The neuropsychological testing consists of a series of tests to assess your memory and concentration (neuropsychological means the way your brain processes and completes specific tasks.) This testing, including directions, will take approximately 3 hours of your time. You will also be asked to complete several questionnaires during your hospital stay. These questionnaires ask for your views about your personality, your childhood experiences your quality of life, your mood and a variety of aspects of your daily functioning. The questionnaires may be completed anytime during your stay and will take about 2.5 hours to finish
The blood draws are done at the GCRC, where you will stay for 2 nights.
The following blood draw procedures will be performed for all participants on Day 1: At 4pm on Day 1, an intravenous line (IV; needle inserted into a vein) will be placed in your arm to draw hourly blood samples used for the measure of adrenocorticotropin (ACTH) and cortisol. ACTH is a hormone that controls the release of cortisol (a stress hormone) in your system and both of these hormones levels change under stressful conditions. The blood samples are taken in small amounts (approximately 1/2 teaspoon) and will be collected at 2pm and 4pm on Baseline Day 1, and then on the hour, every hour, starting at 6pm and ending at 9am the next day. A total of 72 ml(approximately 5 tablespoons) of blood will be drawn. The IV line will be removed following the last blood draw. If you presently live in a time zone different from the Pacific Standard Time zone (for example, Eastern Standard Time zone), we may begin taking hourly blood samples as early as 3pm on Baseline Day 1 in order to more accurately measure your body's daily rhythm of hormones.
The following blood draw procedures will be performed for all participants on Day 2: At 2pm on Baseline Day 2, you will have another IV line placed in your arm to draw hourly blood samples used for the measure of ACTH and Cortisol. At 3pm, you will be given 0.5mg (five 0.1mg tablets) of Fludrocortisone. Cortisol and ACTH are taken in small amounts (approximately 1/2 teaspoon) and will be collected on the hour, every hour, starting at 2 pm and ending at 7pm, then every 30 minutes until 12 midnight. Melatonin will be collected at 6:00pm, 7:00pm and then every 30 minutes until 12 midnight. Following the last blood draw, a blood sample will be taken for a clinical laboratory assessment to ensure your safety following Fludrocortisone administration. A total of 66ml's (4 1/2 tablespoons) of blood will be drawn. At 12 midnight, the IV line will then be removed and your vital signs will be taken.
