title: Agonist selective modulation of tyrosine hydroxylase expression by cannabinoid ligands in a murine neuroblastoma cell line.
abstract: Functional interactions between catecholamines and cannabinoid transmission systems could explain the influence of Delta(9)-tetrahydrocannabinol on several central activities. Hence, the presence of cannabinoid CB(1) receptors in tyrosine hydroxylase (TH) containing cells has been suggested, providing clue for a direct control of catecholamines synthesis. In the present study, we evidenced the constitutive expression of functional cannabinoid CB(1) receptors in N1E-115 neuroblastoma and reported on the use of this model to examine the influence of diverse cannabinoid ligands on TH expression. Exposure of the cells to the high-affinity agonist HU 210 (5 h) resulted in a significant decrease in TH content (pEC(50): 6.40). In contrast, no change was observed after a similar treatment with the structurally unrelated agonist CP 55,940. Besides, the use of a luciferase reporter assay revealed that these two agonists showed opposite influences on TH gene promoter activity. Thus, in cells expressing pTH-luc constructs, inhibition and induction of luciferase activity were respectively observed with HU 210 (pEC(50): 8.95) and CP 55,940 (pEC(50): 9.09). Pharmacological characterisation revealed that these reciprocal responses were both related to the specific activation of cannabinoid CB(1) receptor, suggesting an agonist-dependent modulation of distinct signalling pathways. While these data points out the possible pharmacological manipulation of TH expression by cannabinoid ligands, such approach should take into account the existence of agonist selective trafficking of cannabinoid CB(1) receptor signalling.
authors.affiliation: Unité de Chimie Pharmaceutique et de Radiopharmacie (UCL 7340), Université catholique de Louvain, Brussels, BelgiumLaboratoire de Pharmacologie expérimentale (UCL 5410), Université catholique de Louvain, Brussels, Belgium.
authors.forename: Barbara
authors.initials: B
authors.lastname: Bosier
authors.affiliation: Unité de Chimie Pharmaceutique et de Radiopharmacie (UCL 7340), Université catholique de Louvain, Brussels, BelgiumLaboratoire de Pharmacologie expérimentale (UCL 5410), Université catholique de Louvain, Brussels, Belgium.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Tilleux
authors.affiliation: Unité de Chimie Pharmaceutique et de Radiopharmacie (UCL 7340), Université catholique de Louvain, Brussels, BelgiumLaboratoire de Pharmacologie expérimentale (UCL 5410), Université catholique de Louvain, Brussels, Belgium.
authors.forename: Mustapha
authors.initials: M
authors.lastname: Najimi
authors.affiliation: Unité de Chimie Pharmaceutique et de Radiopharmacie (UCL 7340), Université catholique de Louvain, Brussels, BelgiumLaboratoire de Pharmacologie expérimentale (UCL 5410), Université catholique de Louvain, Brussels, Belgium.
authors.forename: Didier M
authors.initials: DM
authors.lastname: Lambert
authors.affiliation: Unité de Chimie Pharmaceutique et de Radiopharmacie (UCL 7340), Université catholique de Louvain, Brussels, BelgiumLaboratoire de Pharmacologie expérimentale (UCL 5410), Université catholique de Louvain, Brussels, Belgium.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Hermans
mesh_terms: D000818:Animals; D016466:CHO Cells; D063385:Cannabinoid Receptor Modulators / Q000378:metabolism; D002186:Cannabinoids / Q000494:pharmacology*; D002395:Catecholamines / Q000096:biosynthesis*; D045744:Cell Line, Tumor; D006224:Cricetinae; D003412:Cricetulus; D003511:Cyclohexanols / Q000494:pharmacology; D013759:Dronabinol / Q000031:analogs & derivatives / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000235:genetics; D008024:Ligands; D051379:Mice; D008954:Models, Biological; D009447:Neuroblastoma; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology; D018696:Neuroprotective Agents / Q000494:pharmacology; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics; D021381:Protein Transport / Q000187:drug effects / Q000502:physiology; D043884:Receptor, Cannabinoid, CB1 / Q000819:agonists* / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology; D014446:Tyrosine 3-Monooxygenase / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism
chemical_list: D063385:Cannabinoid Receptor Modulators; D002186:Cannabinoids; D002395:Catecholamines; D003511:Cyclohexanols; D008024:Ligands; D018696:Neuroprotective Agents; D043884:Receptor, Cannabinoid, CB1; D013759:Dronabinol; C054649:3-(2-hydroxy-4-(1,1-dimethylheptyl)phenyl)-4-(3-hydroxypropyl)cyclohexanol; D014446:Tyrosine 3-Monooxygenase; C062018:HU 211