Reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in chronic daily cannabis smokers.
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ABSTRACT:
SUBMITTER: Hirvonen J
PROVIDER: S-EPMC3223558 | biostudies-literature | 2012 Jun
REPOSITORIES: biostudies-literature
Publications
Reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in chronic daily cannabis smokers.
Hirvonen J J Goodwin R S RS Li C-T CT Terry G E GE Zoghbi S S SS Morse C C Pike V W VW Volkow N D ND Huestis M A MA Innis R B RB
Molecular psychiatry 20110712 6
Chronic cannabis (marijuana, hashish) smoking can result in dependence. Rodent studies show reversible downregulation of brain cannabinoid CB(1) (cannabinoid receptor type 1) receptors after chronic exposure to cannabis. However, whether downregulation occurs in humans who chronically smoke cannabis is unknown. Here we show, using positron emission tomography imaging, reversible and regionally selective downregulation of brain cannabinoid CB(1) receptors in human subjects who chronically smoke c ...[more]
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