title: Desensitization of D1 dopamine receptors down-regulates the Gs alpha subunit of G protein in SK-N-MC neuroblastoma cells.
abstract: The effect of long-term (72 h) treatment with dopamine D1 receptor agonists, SKF 38393 and dopamine on D1 dopamine receptor and G-protein (Gs alpha) was investigated in SK-N-MC neuroblastoma cells. The prolonged treatment of cells with 10 microM SKF 38393 or 10 microM dopamine resulted in a decrease in dopamine D1 receptor by 41 and 81%, respectively, as measured by specific antagonist [3H]SCH 23390 binding. Similarly, the prolonged treatment of SK-N-MC cells with 10 microM SKF 38393 or 10 microM dopamine resulted in a reduction of the level of Gs alpha subunit of G-protein. The results indicate that agonist-induced down-regulation of D1 dopamine receptor may also modulate G-proteins.
authors.affiliation: Department of Psychiatry, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada.
authors.forename: S K
authors.initials: SK
authors.lastname: Gupta
authors.forename: R K
authors.initials: RK
authors.lastname: Mishra
mesh_terms: D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology*; D001552:Benzazepines / Q000378:metabolism; D002478:Cells, Cultured; D004298:Dopamine / Q000494:pharmacology*; D015259:Dopamine Agents / Q000494:pharmacology*; D015536:Down-Regulation; D004361:Drug Tolerance; D019204:GTP-Binding Proteins / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D009447:Neuroblastoma / Q000473:pathology*; D011954:Receptors, Dopamine / Q000187:drug effects*
chemical_list: D001552:Benzazepines; D015259:Dopamine Agents; D011954:Receptors, Dopamine; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D019204:GTP-Binding Proteins; D004298:Dopamine