This IRB submission, protocol 2005-0829, titled 'Pharmacogenetics, Emotional Reactivity and Smoking Cessation: Genetic Differences in Limbic Activation Associated with Nicotine Withdrawal.' is a grant supplement to the parent grant titled 'Pharmacogenetics, Emotional Reactivity & Smoking' (protocol 2003-1024). The parent grant has received MDACC IRB approval and is currently active. This supplement will ask a subset of patients who are active in the parent grant to undergo 2 fMRI scans, one prior to and one following quitting smoking. Those that agree will sign an informed consent specific to this supplement. Regardless of their decision, patients will continue to participate in the parent grant study (2003-1024). There is no pharmacotherapy specific to this protocol (2005-0829); all patients will receive either bupropion, varenicline, or placebo through the parent grant (2003-1024).
This IRB submission (2005-0829) has the following objectives:
1. To evaluate neural correlates associated with emotional processing during nicotine withdrawal preferentially involving the amygdala and associated areas within the corticolimbic and mesolimbic circuitry. We hypothesize that relative to a pre-quit baseline, post-quit nicotine withdrawal will result in increased activity to negative emotional cues, in contrast to other cues, in one or more areas of interest, and particularly in the right cerebral hemisphere.
2. To determine if bupropion and varenicline moderate patterns of brain activation during post-quit nicotine withdrawal. We hypothesize that relative to placebo, bupropion and varenicline will attenuate the effects of post-quit nicotine withdrawal on emotional processing, reducing activation to negative emotional cues, relative to other cues, in one or more areas of interest, and particularly in the right cerebral hemisphere.
3. To determine if genotype (DRD2 TaqA2 allele and the ins variant of the –141C ins/del DRD2) moderates patterns of brain activation during post-quit nicotine withdrawal. |