Table 3.

Functional imaging studies of the effects of nicotine or cigarette smoking on the dopamine (DA) system

Authors	Subjects	Method	Intervention	Results/conclusions
Dewey et al. (1999)	16 Baboons	11C-Raclopride PET (double bolus)	IV nic (0.3 mg)	↓ DV tracer (indicating ↑ DA concentration) in NAc
Dagher et al. (2001)	11 Smokers; 18 nonsmokers	11C-SCH 23390 PET		↓ BP in smokers (indicating ↓ D1 receptor density) in ventral striatum
Tsukada et al. (2002)	4 Macada mulatto monkeys	11C-Raclopride PET (B/I)	IV nic (B/I)	Slight ↓ BP (indicating ↑ DA concentration) in anesthetized, but not conscious monkeys, in dorsal striatum
Salokangas et al. (2000)	9 Smokers; 10 nonsmokers	18F-DOPA PET		↑ Uptake (indicating ↑ DA activity) in cd and Put of smokers
Krause et al. (2002)	11 Smokers w/ADHD; 11 nonsmokers w/ADHD	[99mTc]TRODAT SPECT		↓ DAT (striatal) in smokers
Staley et al. (2001)	21 Smokers; 21 nonsmokers	[123I] β-CIT SPECT		No overall binding difference between smokers and nonsmokers; ↑ brainstem 5-HT transporters in male smokers
Marenco et al. (2004)	5 Rhesus monkeys	11C-Raclopride PET (double bolus and B/I)	IV nic (0.01–0.06 mg kg−1)	↓ BP (indicating ↑ DA concentration) in basal ganglia with nic administration
Brody et al. (2004b)	20 Smokers	11C-Raclopride PET (B/I)	Single cigarette vs. no smoking	↓ BP (indicating ↑ DA concentration) in smoking, but not no smoking, condition in L ventral cd and put
Barrett et al. (2004)	10 Smokers	11C-Raclopride PET (double bolus)	Smoking every 12 min vs. no smoking	↓ BP correlated with hedonic response to smoking in cd and posterior put

PET positron emission tomography, IV intravenous, nic nicotine, DV volume of distribution, DA dopamine, BP binding potential, B/I bolus-plus-infusion, cd caudate, put putamen, SPECT single photon emission computed tomography, DAT dopamine transporter, ADHD attention deficit hyperactivity disorder, β-CIT 2 β-carbomethoxy-3 β-(4-iodophenyl)-tropane, 5-HT serotonin