INCLUSION CRITERIA:
All subjects must be healthy and aged 18-65 years, with history/physical exam, ECG, and laboratory tests within one year of the PET scan. The volunteer must sign an informed consent form.
EXCLUSION CRITERIA:
-Current psychiatric illness, substance abuse including marijuana use, or severe systemic disease based on history and physical exam.
-Laboratory tests with clinically significant abnormalities or positive urine toxicology screen.
-Prior participation in other research protocols in the last year such that radiation exposure would exceed the annual limits.
-Pregnancy and breast feeding.
-Claustrophobia.
-Presence of ferromagnetic metal in the body or heart pacemaker.
-Positive HIV test.
-Employee of the investigative site or an immediate family member of an employee of the investigative site. Immediate family member is defined as a spouse, parent, child, or sibling, whether biological or legally adopted.
-Employee of Eli Lilly and Company.