Intracerebral microinjections of delta 9-tetrahydrocannabinol: search for the impairment of spatial memory in the eight-arm radial maze in rats.
Nobuaki Egashira, Kenichi Mishima, Katsunori Iwasaki, Michihiro Fujiwara
Brain Research October 18, 2002 DOI: 10.1016/s0006-8993(02)03247-x (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental animal study Peer reviewed |
|---|---|
| Population | Rats |
| Intervention | delta(9)-tetrahydrocannabinol (delta(9)-THC) |
| Dose | 20 micrograms per side |
| Measures | eight-arm radial maze |
| Topics | Cannabis |
| Key findings | Bilateral microinjection of delta(9)-THC (20 micrograms per side) into the dorsal hippocampus, ventral hippocampus, or dorsomedial thalamus impaired spatial memory in the eight-arm radial maze, while injections into 11 other brain regions did not. Dorsomedial thalamus injections also produced perseverative behavior not observed with systemic delta(9)-THC. The authors suggest the dorsal and ventral hippocampus are important sites for delta(9)-THC-induced spatial memory impairment. |
Abstract
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 dorsal hippocampus (DH), ventral hippocampus (VH) or dorsomedial thalamus nucleus (DMT). However, rats treated with delta(9)-THC into DMT produced preseverative behavior which has not been observed by systemic administration of delta(9)-THC. On the other hand, spatial memory was unaffected by microinjections of delta(9)-THC into the other 11 areas examined: frontal (FC) and frontoparietal (FPC) cortex, central (ACE) and basolateral (ABL) amygdaloid nucleus, medial caudate putamen (CPM), lateral hypothalamus (LH), mammillary body (MB), basal forebrain (BF), medial septal nucleus (SEP) and dorsal (DR) and median (MR) raphe nucleus. These results suggest that DH and VH may be important brain sites for the delta(9)-THC-induced impairment of spatial memory.
Comparable studies
Other preclinical and animal studies on cannabis, most cited first.
Citations in the library
Cited by 8
- Susceptibility of the adolescent brain to cannabinoids: long-term hippocampal effects and relevance to schizophrenia Translational Psychiatry November 27, 2012
- Cannabinoids Activate Monoaminergic Signaling to Modulate Key C. elegans Behaviors. Journal of Neuroscience March 15, 2017
- Cellular and intracellular mechanisms involved in the cognitive impairment of cannabinoids. Philosophical transactions of the Royal Society of London. Series B, Biological sciences December 5, 2012
- Involvement of opioid system in cognitive deficits induced by ∆⁹-tetrahydrocannabinol in rats. Psychopharmacology February 2012
- Effects of Endocannabinoid System Modulation on Cognitive and Emotional Behavior Frontiers in Behavioral Neuroscience July 22, 2011
and 3 more in the library
Cites 3
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