PET Detection of CCR2 in Human Atherosclerosis

Inclusion Criteria: Normal Volunteers: 18-40 years of age, non smoker, no history of diabetes, hypertension, or hyperlipidemia. Patients: 50-89 years of age, adequate nutritional status, with or without smoking history, diabetes, hypertension, and hyperlipidema. Both asymptomatic and symptomatic patients with known carotid artery atherosclrosis \>70% and scheduled to undergo surgery. Advanced peripheral artery disease. \- Exclusion Criteria:Inability to receive and sign informed consent. Currently enrolled in another study. Patients who have type 1 diabetes or are in septic shock, receiving steroid therapy, recent history of heavy alcohol consumption, (male \>2 drinks per day, and female \> 1 drink per day. following extreme diets like Atkins or South Beach diet or with Stage 4 chronic renal failure. Patients with unstable clinical condition that in the opinion of the PI precludes participation in the study. Inability to tolerate 60 minutes in a supine position with arms down at sides. Contraindications to MR imaging, (pacemaker, brain aneurysm clips, shrapnel, etc. Positive pregnancy test or lactating. Have another conditions such as cancer or autoimmune/inflammatory diseases, e.g. rheumatoid arthritis or multiple sclerosis that are known to have increased expression of CCR2. \-