Does dopamine mediate the psychosis-inducing effects of cannabis? A review and integration of findings across disciplines

TY - JOUR

T1 - Does dopamine mediate the psychosis-inducing effects of cannabis? A review and integration of findings across disciplines

AU - Kuepper, R.

AU - Morrison, P.D.

AU - van Os, Jim

AU - Murray, R.M.

AU - Kenis, G.

AU - Henquet, C.

PY - 2010/8

Y1 - 2010/8

N2 - General population epidemiological studies have consistently found that cannabis use increases the risk of developing psychotic disorders in a dose-dependent manner. While the epidemiological signal between cannabis and psychosis has gained considerable attention, the biological mechanism whereby cannabis increases risk for psychosis remains poorly understood. Animal research suggests that delta-9-tetrahydrocannabinol (THC, the main psychoactive component of cannabis) increases dopamine levels in several regions of the brain, including striatal and prefrontal areas. Since dopamine is hypothesized to represent a crucial common final pathway between brain biology and actual experience of psychosis, a focus on dopamine may initially be productive in the examination of the psychotomimetic effects of cannabis. Therefore, this review examines the evidence concerning the interactions between THC, endocannabinoids and dopamine in the cortical as well as subcortical regions implicated in psychosis, and considers possible mechanisms whereby cannabis-induced dopamine dysregulation may give rise to delusions and hallucinations. It is concluded that further study of the mechanisms underlying the link between cannabis and psychosis may be conducted productively from the perspective of progressive developmental sensitization, resulting from gene-environment interactions. (C) 2010 Elsevier B.V. All rights reserved.

AB - General population epidemiological studies have consistently found that cannabis use increases the risk of developing psychotic disorders in a dose-dependent manner. While the epidemiological signal between cannabis and psychosis has gained considerable attention, the biological mechanism whereby cannabis increases risk for psychosis remains poorly understood. Animal research suggests that delta-9-tetrahydrocannabinol (THC, the main psychoactive component of cannabis) increases dopamine levels in several regions of the brain, including striatal and prefrontal areas. Since dopamine is hypothesized to represent a crucial common final pathway between brain biology and actual experience of psychosis, a focus on dopamine may initially be productive in the examination of the psychotomimetic effects of cannabis. Therefore, this review examines the evidence concerning the interactions between THC, endocannabinoids and dopamine in the cortical as well as subcortical regions implicated in psychosis, and considers possible mechanisms whereby cannabis-induced dopamine dysregulation may give rise to delusions and hallucinations. It is concluded that further study of the mechanisms underlying the link between cannabis and psychosis may be conducted productively from the perspective of progressive developmental sensitization, resulting from gene-environment interactions. (C) 2010 Elsevier B.V. All rights reserved.

U2 - 10.1016/j.schres.2010.05.031

DO - 10.1016/j.schres.2010.05.031

M3 - Literature review

SN - 1573-2509

VL - 121

SP - 107

EP - 117

JO - Schizophrenia Research

JF - Schizophrenia Research

IS - 1-3

ER -