Role of cortical cannabinoid CB1 receptor in conditioned taste aversion memory.
The brain endocannabinoid system has been shown to play a role in memory, though the extent to which this role generalizes over different types and processes of memory is not yet determined. Here we show that the cannabinoid receptor 1 (CB1) plays differential roles in acquisition, extinction and reconsolidation of conditioned taste aversion (CTA) memory in the rat insular cortex, which contains the taste cortex. Activation of the CB1 receptor in the insular cortex inhibits acquisition and reconsolidation but not extinction, whereas blockade of the CB1 receptor promotes memory and blocks extinction of CTA, while having no apparent effect on reconsolidation. The CB1 ligands used in this study were incapable of substituting the unconditioned stimulus in CTA training. All in all, the data raise the possibility that the state of activity of the CB1 receptor in the insular cortex contributes to the encoding of hedonic valence that enters into association with taste items.
Kobilo
Tali
T
Department of Neurobiology, The Weizmann Institute of Science, Rehovot 76100, Israel.
Hazvi
Shoshi
S
Dudai
Yadin
Y
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology*; D001522:Behavior, Animal / Q000187:drug effects; D048588:Benzoxazines / Q000494:pharmacology; D002540:Cerebral Cortex / Q000378:metabolism*; D003214:Conditioning, Classical / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D009025:Morpholines / Q000494:pharmacology; D009281:Naphthalenes / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D043884:Receptor, Cannabinoid, CB1 / Q000819:agonists / Q000502:physiology*; D013649:Taste / Q000187:drug effects
D048588:Benzoxazines; D009025:Morpholines; D009281:Naphthalenes; D043884:Receptor, Cannabinoid, CB1; C070417:(3R)-((2,3-dihydro-5-methyl-3-((4-morpholinyl)methyl)pyrrolo-(1,2,3-de)-1,4-benzoxazin-6-yl)(1-naphthalenyl))methanone