title: Repeated exposure to delta 9-tetrahydrocannabinol reduces prefrontal cortical dopamine metabolism in the rat.
abstract: Long-term abuse of marijuana by humans can induce profound behavioral deficits characterized by cognitive and memory impairments. In particular, deficits on tasks dependent on frontal lobe function have been reported in cannabis abusers. In the current study, we examined whether long-term exposure to delta9-tetrahydrocannabinol, the active ingredient in marijuana, altered the neurochemistry of the frontal cortex in rats. Two weeks administration of delta9-tetrahydrocannabinol reduced dopamine transmission in the medial prefrontal cortex, while dopamine metabolism in striatal regions was unaffected. These data are consistent with earlier findings of dopaminergic regulation of frontal cortical cognition. Thus, cognitive deficits in heavy abusers of cannabis may be subserved by drug-induced alterations in frontal cortical dopamine transmission.
authors.affiliation: Section of Neurobiology, Yale University School of Medicine, New Haven, CT 06510, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Jentsch
authors.forename: C D
authors.initials: CD
authors.lastname: Verrico
authors.forename: D
authors.initials: D
authors.lastname: Le
authors.forename: R H
authors.initials: RH
authors.lastname: Roth
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis; D000818:Animals; D003342:Corpus Striatum / Q000737:chemistry / Q000187:drug effects; D004298:Dopamine / Q000032:analysis / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D013759:Dronabinol / Q000008:administration & dosage / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D008297:Male; D009714:Nucleus Accumbens / Q000737:chemistry / Q000187:drug effects; D017397:Prefrontal Cortex / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013995:Time
chemical_list: D015102:3,4-Dihydroxyphenylacetic Acid; D013759:Dronabinol; D004298:Dopamine