“Nicotinic Hepatic Metabolism on Neuroreceptor Substrates of Nicotine Addiction”
Physically healthy adult smokers may be eligible for this study. Volunteers may participate in this study if they are 18 - 65 years old. Subjects will participate in two separate 10-hour PET/CT Scan Sessions (each with 2 hours of actual PET/CT scanning): one following an overnight abstinence and one following two overnights of abstinence. To achieve and confirm two overnights of abstinence, participants will present to the inpatient CHPS the day prior to the scheduled scan and stay overnight. The 2-[18F]-FA PET/CT brain scans will consist of an injection followed by an 8-hour infusion of 2-[18F]-FA. The scan session will begin at approximately 6 hours after the bolus injection. The PET/CT scan will be approximately 120 minutes long with a bolus injection of IV nicotine that will occur during scanning at approximately 30 minutes into the procedure. The pre and post nicotine images will be analyzed to evaluate for differences in receptor uptake after the nicotine "challenge". Subjects will have a structural Brain MRI performed within 1 year of study enrollment. Subjects who have not had a Brain MRI that is deemed acceptable for use for this study will undergo a research Brain MRI.
Drug - 2-[18F]-FA PET/CT
2-[18F]FA is a highly specific radiotracer which has been used successfully to image nicotinic acetylcholine receptors in the human brain to characterize the effects of nicotine exposure (via smoking) on these receptors.
Drug - I.V. Nicotine
Subjects in our study will receive intravenous nicotine at the adaptation session and each of the PET scans, close to the amount of nicotine absorbed from smoking 1/10 cigarette.
The Influence of Nicotinic Hepatic Metabolism on Neuroreceptor Substrates of Nicotine Addiction