Delta(9)-tetrahydrocannabinol decreases extracellular GABA and increases extracellular glutamate and dopamine levels in the rat prefrontal cortex: an in vivo microdialysis study.
Cannabinoid modulation of prefrontal cortex and hippocampus neuronal functioning has been correlated to the disruptive action of marijuana on memory tasks. This study investigates the effects of delta(9)-tetrahydrocannabinol (delta(9)-THC) on dopamine, glutamate and GABA levels in vivo by brain microdialysis in the prefrontal cortex. Delta(9)-THC (1 mg/kg, i.v.) significantly increased extracellular dopamine and glutamate levels and decreased GABA levels. These effects were prevented by the cannabinoid antagonist SR141716A (1 mg/kg, i.v.), which per se was ineffective. These results suggest that delta(9)-THC disrupt the normal interplay between neurotransmitters in this area and may bear relevance in understanding neuronal mechanisms underlying cannabinoid-induced cognitive deficits.
Pistis
Marco
M
BB Brodie Department of Neuroscience, University of Cagliari, Cittadella Universitaria SS 554, 09042 Monserrato (CA), Italy. mpistis@unica.it
Ferraro
Luca
L
Pira
Luigi
L
Flore
Giovanna
G
Tanganelli
Sergio
S
Gessa
Gian Luigi
GL
Devoto
Paola
P
D000818:Animals; D004298:Dopamine / Q000032:analysis / Q000378:metabolism*; D013759:Dronabinol / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D005110:Extracellular Space / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D018698:Glutamic Acid / Q000032:analysis / Q000378:metabolism; D008297:Male; D017551:Microdialysis; D010880:Piperidines / Q000494:pharmacology; D017397:Prefrontal Cortex / Q000187:drug effects / Q000378:metabolism*; D011619:Psychotropic Drugs / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000037:antagonists & inhibitors; D000077285:Rimonabant; D005680:gamma-Aminobutyric Acid / Q000032:analysis / Q000378:metabolism*
D010880:Piperidines; D011619:Psychotropic Drugs; D011720:Pyrazoles; D011955:Receptors, Drug; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D013759:Dronabinol; D000077285:Rimonabant; D004298:Dopamine