SCIENTIFIC SUMMARY The project will, in a sample of cocaine-dependent (CD) and healthy control (HC) subjects, use administration of Corticorelin, a synthetic form of corticotropin releasing factor (CRF)and PET imaging to assess dopamine (DA) transmission in addiction. We will use [11C]-(+)-PHNO PET to measure striatal DA receptor binding on two occasions: 1) following corticorelin administration and 2) following saline. The change in receptor binding between the two occasions (i.e., displacement of [11C]-(+)-PHNO by endogenous DA) will index DA release.~SUBJECTS CD subjects will meet DSM-IV criteria for abuse or dependence and be ~10d cocaine abstinent at the time of PET. HC will be recruited to match CD on age, sex, education, and cigarette smoking.~PRIMARY OUTCOME MEASURES We will measure [11C]-(+)-PHNO binding on two occasions (corticorelin, saline), with the difference between conditions indexing dopamine release; this measure will then be compared between cocaine-dependent and control subjects. We will also measure plasma cortisol and ACTH), physiological measures, and subjective craving and mood.
This study will, in a sample of cocaine-dependent and healthy control subjects, administer corticorelin and compare dopamine release between groups. Dopamine release will be measured using PET neuroimaging with the radiotracer [11C]-(+)-PHNO.