Cannabinoid ligand-receptor signaling in the mouse uterus.
Using RNA (Northern) blot hybridization and reverse transcription-PCR, we demonstrate that the brain-type cannabinoid receptor (CB1-R) mRNA, but not the spleen-type cannabinoid receptor (CB2-R) mRNA, is expressed in the mouse uterus and that this organ has the capacity to synthesize the putative endogenous cannabinoid ligand, anandamide (arachidonylethanolamide). The psychoactive cannabinoid component of marijuana--delta 9-tetrahydrocannabinol (THC)--or anandamide, but not the inactive and nonpsychoactive cannabidiol (CBD), inhibited forskolin-stimulated cyclic AMP formation in the mouse uterus, which was prevented by pertussis toxin pretreatment. These results suggest that uterine CB1-R is coupled to inhibitory guanine nucleotide-binding protein and is biologically active. Autoradiographic studies identified ligand binding sites ([3H]anandamide) in the uterine epithelium and stromal cells, suggesting that these cells are perhaps the targets for cannabinoid action. Scatchard analysis of the binding of [3H]WIN 55212-2, another cannabinoid receptor ligand, showed a single class of high-affinity binding sites in the endometrium with an apparent Kd of 2.4 nM and Bmax of 5.4 x 10(9) molecules per mg of protein. The gene encoding lactoferrin is an estrogen-responsive gene in the mouse uterus that was rapidly and transiently up-regulated by THC, but not by CBD, in ovariectomized mice in the absence of ovarian steroids. This effect, unlike that of 17 beta-estradiol (E2), was not influenced by a pure antiestrogen, ICI 182780, suggesting that the THC-induced uterine lactoferrin gene expression does not involve estrogen receptors. We propose that the uterus is a new target for cannabinoid ligand-receptor signaling.
Das
S K
SK
Department of Physiology, University of Kansas Medical Center, Ralph L. Smith Research Center, Kansas City 66160-7338, USA.
Paria
B C
BC
Chakraborty
I
I
Dey
S K
SK
D000818:Animals; D001095:Arachidonic Acids / Q000378:metabolism / Q000494:pharmacology; D001345:Autoradiography; D001483:Base Sequence; D015152:Blotting, Northern; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002185:Cannabidiol / Q000494:pharmacology; D002186:Cannabinoids / Q000494:pharmacology*; D002188:Cannabis; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D017931:DNA Primers; D013759:Dronabinol / Q000494:pharmacology; D063388:Endocannabinoids; D005260:Female; D019204:GTP-Binding Proteins / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D037342:Pertussis Toxin; D016133:Polymerase Chain Reaction; D053284:Polyunsaturated Alkamides; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug / Q000096:biosynthesis / Q000502:physiology*; D015398:Signal Transduction; D014316:Tritium; D014599:Uterus / Q000187:drug effects / Q000502:physiology*; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D001095:Arachidonic Acids; D002121:Calcium Channel Blockers; D002186:Cannabinoids; D017931:DNA Primers; D063388:Endocannabinoids; D053284:Polyunsaturated Alkamides; D012333:RNA, Messenger; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug; D010566:Virulence Factors, Bordetella; D014316:Tritium; D002185:Cannabidiol; D005576:Colforsin; D013759:Dronabinol; D000242:Cyclic AMP; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; C078814:anandamide