Cannabis is a widely used illicit substance. ∆(9)-Tetrahydrocannabinol (THC), the major psychoactive component of cannabis, is known to induce cognitive deficits that closely resemble the impairment observed in schizophrenic patients. We previously reported that THC (6 mg/kg) impairs spatial memory in the eight-arm radial maze, and that this memory disturbance was reversed by the cannabinoid...
To clarify the mechanism by which Delta9-tetrahydrocannabinol, a major psychoactive component of marijuana, impairs spatial memory in the 8-arm radial maze in rats via the cholinergic system, we used two acetylcholinesterase inhibitors, physostigmine and tetrahydroaminoacridine. Moreover, we examined the effect of Delta9-tetrahydrocannabinol on acetylcholine release in the frontal cortex and...
The purpose of this study was to identify brain sites that contribute to the delta(9)-tetrahydrocannabinol (delta(9)-THC)-induced impairment of spatial memory in rats. Rats were tested in the eight-arm radial maze after microinjections of delta(9)-THC into one of 14 different brain regions. The bilateral microinjection of delta(9)-THC (20 microg/side) impaired spatial memory when injected into...
The present study investigated the involvement of the serotonin (5-hydroxytryptamine, 5-HT) neuronal system in the Delta(9)-tetrahydrocannabinol-induced impairment of spatial memory in the eight-arm radial maze in rats. Delta(9)-Tetrahydrocannabinol (6 mg/kg, i.p.), which impairs spatial memory, significantly increased the 5-HT content in the ventral hippocampus. A microdialysis study showed...