NicotineNicotinic AgonistsTobacco Use DisorderGanglionic StimulantsWeight GainReceptors, NicotinicMecamylamineCotinineNicotinic AntagonistsChewing GumSubstance Withdrawal SyndromeTobacco Use Cessation ProductsSmoking CessationSmokingAdministration, CutaneousDihydro-beta-ErythroidineTarsalpha7 Nicotinic Acetylcholine ReceptorSelf AdministrationDose-Response Relationship, DrugAzocinesRats, Sprague-DawleyAconitineConditioning, OperantRewardQuinolizinesTime FactorsTobacco, SmokelessTobacco ProductsTobaccoAnabasineBehavior, AnimalBicyclo Compounds, HeterocyclicReinforcement (Psychology)Carbon MonoxideSelf StimulationAnalysis of VarianceHexamethoniumDopamineBenzazepinesTobacco Smoke PollutionBungarotoxinsHexamethonium CompoundsMotor ActivityQuinoxalinesVentral Tegmental AreaBrainMice, Inbred C57BLBody WeightPyridinesNitrosaminesSmokePrenatal Exposure Delayed EffectsNucleus Accumbens