Ventral striatal blood flow is altered by acute nicotine but not withdrawal from nicotine.
Neural mechanisms underlying the reinforcing effects of nicotine and other drugs have been widely studied and are known to involve the ventral striatum, which is part of the mesocorticolimbic dopamine system. In contrast, mechanisms of nicotine withdrawal have received less attention although subjective withdrawal likely contributes to the difficulty of quitting. The goal of this study was to determine if nicotine withdrawal was associated with alterations of cerebral blood flow (CBF) in ventral striatum. Twelve smokers, moderately dependent on nicotine, underwent MR dynamic susceptibility contrast (DSC) imaging at baseline, after overnight withdrawal from nicotine, and after nicotine replacement. DSC images were used to calculate CBF in three regions of interest: ventral striatum, thalamus, and medial frontal cortex. Subjective withdrawal symptoms were measured at each time point. In spite of significant subjective withdrawal symptoms, there was no main effect of withdrawal on CBF in the three regions. However, there was a significant correlation between the increase in withdrawal symptoms and a reduction in thalamic CBF. In contrast to withdrawal, nicotine replacement significantly increased CBF in ventral striatum. Our findings are consistent with the known role of ventral striatum in drug reward. The lack of a main effect on withdrawal, but correlation of thalamic blood flow with withdrawal symptoms suggests that more complex mechanisms mediate the subjective features of the withdrawal state.
Tanabe
Jody
J
Department of Radiology, University of Colorado at Denver Health Sciences, Denver, CO 80262, USA. jody.tanabe@uchsc.edu
Crowley
Thomas
T
Hutchison
Kent
K
Miller
David
D
Johnson
Glyn
G
Du
Yiping P
YP
Zerbe
Gary
G
Freedman
Robert
R
D000328:Adult; D000465:Algorithms; D001794:Blood Pressure / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects; D002638:Chewing Gum; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D017072:Neostriatum / Q000098:blood supply* / Q000187:drug effects; D009538:Nicotine / Q000008:administration & dosage / Q000009:adverse effects* / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000008:administration & dosage / Q000009:adverse effects* / Q000494:pharmacology*; D012727:Sex Characteristics; D012907:Smoking / Q000009:adverse effects / Q000503:physiopathology; D013375:Substance Withdrawal Syndrome / Q000503:physiopathology*; D011795:Surveys and Questionnaires; D013788:Thalamus / Q000098:blood supply / Q000187:drug effects
D002638:Chewing Gum; D018722:Nicotinic Agonists; D009538:Nicotine