title: History of cannabis use is not associated with alterations in striatal dopamine D2/D3 receptor availability.
abstract: Cannabis use in adolescence is emerging as a risk factor for the development of psychosis. In animal studies, Δ9-tetrahydrocannabinol (THC), the psychoactive component of cannabis, modulates striatal dopaminergic neurotransmission. Alterations in human striatal dopaminergic function have also been reported both in psychosis and in stimulant use. We sought to examine whether striatal dopamine D(2)/D(3) receptor availability was altered in volunteers with a history of cannabis use using a database of previously acquired [(11)C]-raclopride positron emission tomography (PET) scans. Ten [(11)C]-raclopride scans from volunteers with a history of cannabis use were compared to ten control scans using a functional striatal subdivision region of interest (ROI) analysis. No significant differences in either overall striatal BP(ND) values or BP(ND) values in any functional striatal subdivision were found between the two groups. There was also no correlation between lifetime frequency of cannabis use and BP(ND) values. Limbic striatal BP(ND) values were ten percent lower in current nicotine cigarette smokers. These findings suggest that, unlike other drugs of abuse, a history of cannabis use is not associated with alterations in striatal dopamine D(2)/D(3) receptor availability.
authors: Psychiatric Imaging Group, MRC Clinical Sciences Centre, Imperial College London, London, UK. paul.stokes@imperial.ac.uk
authors: Paul R A
authors: PR
authors: Stokes
authors: Alice
authors: A
authors: Egerton
authors: Ben
authors: B
authors: Watson
authors: Alistair
authors: A
authors: Reid
authors: Julia
authors: J
authors: Lappin
authors: Oliver D
authors: OD
authors: Howes
authors: David J
authors: DJ
authors: Nutt
authors: Anne R
authors: AR
authors: Lingford-Hughes
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects; D002188:Cannabis; D002247:Carbon Isotopes; D003342:Corpus Striatum / Q000378:metabolism*; D005260:Female; D006801:Humans; D008032:Limbic System / Q000187:drug effects / Q000378:metabolism; D008297:Male; D002189:Marijuana Abuse / Q000378:metabolism*; D009538:Nicotine / Q000009:adverse effects; D049268:Positron-Emission Tomography; D011618:Psychotic Disorders / Q000378:metabolism; D020891:Raclopride; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D050637:Receptors, Dopamine D3 / Q000378:metabolism*; D009435:Synaptic Transmission / Q000187:drug effects
chemical_list: D002247:Carbon Isotopes; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D020891:Raclopride; D009538:Nicotine