Anandamide and WIN 55212-2 inhibit cyclic AMP formation through G-protein-coupled receptors distinct from CB1 cannabinoid receptors in cultured astrocytes.
The effects of anandamide and the cannabinoid receptor agonists WIN 55212-2 and CP 55940 on the evoked formation of cyclic AMP were compared in cultured neurons and astrocytes from the cerebral cortex and striatum of mouse embryos. The three compounds inhibited the isoproterenol-induced accumulation of cyclic AMP in neuronal cells, and these responses were blocked by the selective CB1 receptor antagonist SR 141716A. The three agonists were more potent in cortical than striatal neurons. Interestingly, WIN 55212-2, CP 55940 and anandamide also inhibited the isoproterenol-evoked accumulation of cyclic AMP in astrocytes but, in contrast to WIN 55212-2 and CP 55940, anandamide was much more potent in striatal than cortical astrocytes. Inhibition was prevented by pertussis toxin pretreatment, but not blocked by SR 141716A. Therefore, G-protein-coupled receptors, distinct from CB1 receptors, are involved in these astrocytic responses. Moreover, specific binding sites for [3H]-SR 141716A were found in neurons but not astrocytes. Furthermore, using a polyclonal CB1 receptor antibody, staining was observed in striatal and cortical neurons, but not in striatal and cortical astrocytes. Taken together, these results suggest that glial cells possess G-protein-coupled receptors activated by cannabinoids distinct from the neuronal CB1 receptor, and that glial cells responses must be taken into account when assessing central effects of cannabinoids.
Sagan
S
S
INSERM U114, Collège de France, Paris. sagan@ccr.jussieu.fr
Venance
L
L
Torrens
Y
Y
Cordier
J
J
Glowinski
J
J
Giaume
C
C
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology*; D001253:Astrocytes / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism; D048588:Benzoxazines; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D003342:Corpus Striatum / Q000166:cytology; D000242:Cyclic AMP / Q000378:metabolism*; D063388:Endocannabinoids; D019204:GTP-Binding Proteins / Q000378:metabolism; D007545:Isoproterenol / Q000494:pharmacology; D051379:Mice; D009025:Morpholines / Q000494:pharmacology*; D009281:Naphthalenes / Q000494:pharmacology*; D009474:Neurons / Q000737:chemistry / Q000166:cytology / Q000187:drug effects; D037342:Pertussis Toxin; D010880:Piperidines / Q000494:pharmacology; D053284:Polyunsaturated Alkamides; D011720:Pyrazoles / Q000494:pharmacology; D051381:Rats; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug / Q000819:agonists / Q000032:analysis / Q000378:metabolism*; D000077285:Rimonabant; D014316:Tritium; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D000318:Adrenergic beta-Agonists; D001095:Arachidonic Acids; D048588:Benzoxazines; D002121:Calcium Channel Blockers; D063388:Endocannabinoids; D009025:Morpholines; D009281:Naphthalenes; D010880:Piperidines; D053284:Polyunsaturated Alkamides; D011720:Pyrazoles; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug; D010566:Virulence Factors, Bordetella; D014316:Tritium; C070417:(3R)-((2,3-dihydro-5-methyl-3-((4-morpholinyl)methyl)pyrrolo-(1,2,3-de)-1,4-benzoxazin-6-yl)(1-naphthalenyl))methanone; D000242:Cyclic AMP; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D007545:Isoproterenol; D000077285:Rimonabant; C078814:anandamide