PET Scanning of Adults With Attention Deficit Hyperactivity Disorder (ADHD)

Study Summary

This study will explore the brain in men with and without attention deficit hyperactivity disorder (ADHD). It will use positron emission tomography (PET) and magnetic resonance imaging (MRI) to study brain function and nerve cell communication involving phospholipids (fatty molecules that make up the covering of nerve cell fibers in the brain and are involved in communication between the cells). It will also look at how nerve cell communication is related to blood flow. In particular, the study will explore communication through the dopamine system, which is one of the main neurotransmitter systems in the brain involved in ADHD. Healthy men and men with ADHD between 18 and 55 years of age may be eligible for this study. Participants undergo the following procedures: "\<TAB\>Medical history and psychiatric and medical evaluation, including blood and urine tests. "\<TAB\>MRI scan. This test uses a strong magnetic field and radio waves to obtain images of the brain. The subject lies still on a table that slides into the scanner (a metal cylinder) during the scanning. "\<TAB\>PET scanning. The subject lies on the scanner bed with his head held still using a special facemask. A catheter (plastic tube or needle) is placed in an artery to collect blood samples and in a vein to inject radioactive isotopes for measuring blood flow and phospholipid metabolism. Scans are done after an injection of a saline solution and again after injection of apomorphine, a medication that turns on dopamine receptors in the brain. The injections are given under the skin of the abdomen, about one and a half hours apart....