Thirty-five www.selleckchem.com/products/DAPT-GSI-IX.html subjects were found to be eligible, and 30 subjects completed the study. Demographic and smoking variables are presented in Table 1. Table 1. Demographic and Smoking Variables for all Subjects for Study 1 (n = 30) and by Medication Group for Study 2 (n = 62) Design This study was a mixed design that examined varying levels of nicotine deprivation on smoking lapse behavior modeled in the laboratory. Nicotine deprivation (1, 6, or 18 hr) was a within-subject factor, and monetary reinforcement ($0.25, $0.50, $1.00) was a fully crossed between-subjects variable (n = 10 per cell). The study consisted of an intake session and three laboratory sessions (order of sessions was randomly determined). Subjects were paid $349 for completing the study. Payments were provided by check 2�C3 weeks following study completion.

Procedures Intake Sessions The study was approved by the Yale University Human Investigation Committee, and written informed consent was obtained at the start of the intake session. The Structured Clinical Interview for DSM-IV (First, Spitzer, Gibbon, & Williams, 1997) was used to evaluate Axis I disorders. The Timeline Followback (Toll, Cooney, McKee, & O��Malley, 2005) was used to assess past 30-day smoking behavior. Expired breath carbon monoxide (CO) levels were assessed using a CO-meter (MCO2 Monitor, MicroDirect, Auburn, ME). The absence of recent cocaine, opiate, benzodiazepine, barbiturate, or amphetamine use was determined by urine drug test (JANT Pharmaceuticals, Encino, CA).

Nicotine Deprivation Conditions For the 18-hr deprivation condition, subjects were instructed to have their last cigarette at 10 p.m., the prior evening. Compliance was biochemically confirmed initially with CO readings (less than 50% of their CO level at intake) Cilengitide and later with serum nicotine levels (all <4 ng/ml). Volunteers who failed to comply with instructions were rescheduled. For the 6-hr deprivation condition, subjects were able to smoke as they normally would before the laboratory session and had their last cigarette at 10 a.m. Subjects in the 1-hr deprivation condition were able to smoke whenever they wished until 3 p.m. when they smoked a final cigarette. Across the three laboratory sessions, there were no differences in baseline serum cotinine indicating similar recent nicotine exposure (overall mean = 233.16 ng/ml, SE = 18.58). Laboratory Sessions Each subject completed three 9-hr laboratory sessions which took place at the Yale Center for Clinical Investigation. Laboratory sessions were scheduled within 14 days of each other. Time between sessions was not a significant covariate of the primary outcomes.