Delta(9)-tetrahydrocannabinol-induced alterations in limbic system glucoseuse in the rat

The effects of Delta (9)-tetrahydrocannabinol (THC) on neural activity in t he rat were investigated using [C-14]2-deoxyglucose autoradiography to meas ure local cerebral glucose use. Overall, THC reduced glucose use at 5 mg/kg and slightly increased it. at 1 mg/kg. Significant reductions were seen at the higher dose in regions of the hippocampus and limbic. system, and in s tructures associated with sensory and sensorimotor processing, consistent w ith the effects of-THC on memory, sensory perception and motor control. Glu cose use was increased in the shell of the nucleus accumbens at 1 mg/kg but not reduced at 5 mg/kg. This may reflect increases in activity in mesolimb ic reward pathways which at the higher dose are mitigated by reduced glutam atergic outflow from the hippocampus. (C) 2001 Lippincott Williams & Wilkin s.