A substantial body of evidence implicates the endogenous opioid system, and the mu opioid receptor (MOR) in particular, in the reinforcing effects of drugs of abuse, including nicotine. A single nucleotide polymorphism (SNP) in the mu opioid receptor gene (OPRM1 Asp40) is associated with the ability to quit smoking, as well as nicotine reward and withdrawal symptoms. However, the precise mechanism through which this SNP influences nicotine dependence remains unresolved. This positron emission tomography (PET) study will examine whether this OPRM1 SNP alters MOR binding in response to nicotine in human smokers. Specifically, we will use [11 C]carfentanil PET imaging to assess the effects of intravenous (IV) nicotine versus saline (within-subject) on MOR binding potential in 24 chronic smokers genotyped prospectively and stratified by OPRM1 genotype.
Name: Nicotine
Description: Participants shall receive an intravenous injection of nicotine during their practice session and one of their PET scans (double-blind). The dose of IV nicotine will be 1mg/70kg and the maximum dose that shall be injected is 1.2mg.Type: DrugOPRM1 A118G AA genotype OPRM1 A118G AG or GG genotype
Case-Crossover
There is one SNP
Functional Characterization of OPRM1 A118G in Nicotine Dependence: IV Nicotine Study. --- A118G ---