Enhanced dopamine release by nicotine in cigarette smokers: a double-blind, randomized, placebo-controlled pilot study.
Previous studies of smoking on dopamine release in humans were investigated only in smokers. Using nicotine gum, we examined the effect of nicotine on dopamine release in smokers and non-smokers and its relation to the degree of nicotine dependence. Smokers and non-smokers participated in a double-blind, randomized, placebo-controlled cross-over study. They participated in two PET measurements with [11C]raclopride, in which they received either nicotine or placebo. Changes in [11C]raclopride non-displaceable binding potential (BPND) following nicotine administration were quantified. Smokers showed significant decrease in BP in the striatum following nicotine administration, but non-smokers did not show such a decrease. The BPND difference between the two scanning sessions was correlated with the degree of nicotine dependence. The BPND difference might reflect enhanced dopamine release in smokers and the reinforced effect of nicotine. These data suggest the feasibility of our gum method as well as the importance of the degree of dependence in future studies of the nicotine effect on the dopamine system.
Takahashi
Hidehiko
H
Department of Molecular Neuroimaging, National Institute of Radiological Sciences, Anagawa, Inage-ku, Chiba, Japan.
Fujimura
Yota
Y
Hayashi
Mika
M
Takano
Harumasa
H
Kato
Motoichiro
M
Okubo
Yoshiro
Y
Kanno
Iwao
I
Ito
Hiroshi
H
Suhara
Tetsuya
T
D004298:Dopamine / Q000378:metabolism*; D018492:Dopamine Antagonists; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D017072:Neostriatum / Q000000981:diagnostic imaging / Q000187:drug effects; D009538:Nicotine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D018722:Nicotinic Agonists / Q000008:administration & dosage*; D010865:Pilot Projects; D011109:Polymethacrylic Acids / Q000008:administration & dosage*; D011145:Polyvinyls / Q000008:administration & dosage*; D049268:Positron-Emission Tomography; D020891:Raclopride; D012907:Smoking / Q000188:drug therapy* / Q000378:metabolism*; D061485:Tobacco Use Cessation Devices
D018492:Dopamine Antagonists; D018722:Nicotinic Agonists; D011109:Polymethacrylic Acids; D011145:Polyvinyls; D020891:Raclopride; D009538:Nicotine; D004298:Dopamine