title: Induction and activation of mitogen-activated protein kinases of human lymphocytes as one of the signaling pathways of the immunomodulatory effects of morphine sulfate.
abstract: Morphine sulfate causes immunomodulatory and immunosuppressive effects in human. In this study, the signaling pathway involved in these morphine effects was studied. Addition of morphine sulfate to human CEMx174 lymphocytic cells resulted in increased expression of mitogen-activated protein kinase cascade proteins. Morphine enhanced the cellular levels of ERK1 (44 kDa), ERK2 (42 kDa), a 54-kDa ERK, MEK1 (45 kDa), and MEKK (78 kDa). A time-dependent increase in the activated (Thr and Tyr dually phosphorylated) state of ERK1 and ERK2 was also observed. Naloxone, a morphine antagonist, reversed the observed morphine effects, implicating a micro opioid receptor-mediated process. These findings suggest that mitogen-activated protein kinases are important intermediates in signal transduction pathways initiated by morphine receptors in immune cells.
authors.affiliation: Department of Medical Pharmacology and Toxicology, School of Medicine, University of California, Davis, California 95616, USA.
authors.forename: L F
authors.initials: LF
authors.lastname: Chuang
authors.forename: K F
authors.initials: KF
authors.lastname: Killam
authors.forename: R Y
authors.initials: RY
authors.lastname: Chuang
mesh_terms: D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000096:biosynthesis / Q000378:metabolism*; D002460:Cell Line; D004790:Enzyme Induction; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D048369:MAP Kinase Kinase 1; D048728:MAP Kinase Kinase Kinase 1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D009020:Morphine / Q000494:pharmacology*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D009020:Morphine; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048728:MAP Kinase Kinase Kinase 1; C482576:MAP3K1 protein, human; D048369:MAP Kinase Kinase 1; C482125:MAP2K1 protein, human; D020929:Mitogen-Activated Protein Kinase Kinases