Six days after intracerebroventricular pretreatment of rats with pertussis toxin (PTX 0.5 microgram/rat) there was a marked decrease in the antinociceptive effect of morphine, regardless of the route of opioid administration (into the periaqueductal gray matter, intrathecally or intraperitoneally) or the analgesic test used (tail flick and jaw opening reflex). PTX pretreatment also partially attenuated the naloxone-precipitated withdrawal syndrome in morphine-dependent rats, significantly reducing teeth chattering, rearing and grooming. These in vivo findings indicate that G-protein-dependent mechanisms are involved in morphine analgesia and dependence. The biochemical mechanism could be related to ADP ribosylation of Gi coupled to the adenylate cyclase system, but an interaction of PTX with other G-proteins linked to different second messengers or directly to ionic channels cannot be excluded.
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http://dx.doi.org/10.1016/0091-3057(90)90218-7 | DOI Listing |
Sci Rep
January 2025
Department of Biomedical Engineering, Graduate School of Medicine, Science and Technology, Shinshu University, Nagano, 390-8621, Japan.
Lysophosphatidylethanolamine (LPE) is a bioactive lipid mediator involved in diverse cellular functions. In this study, we investigated the effects of three LPE species, 1-palmitoyl LPE (16:0 LPE), 1-stearoyl LPE (18:0 LPE), and 1-oleoyl LPE (18:1 LPE) on pre-osteoblast MC3T3-E1 cells. All LPE species stimulated cell proliferation and activated the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) 1/2.
View Article and Find Full Text PDFBrain
December 2024
Neuroimmunology Program, Fundació Clínic per la Recerca Biomèdica - Institut d'Investigacions Biomèdiques August Pi i Sunyer (FCRB-IDIBAPS), Barcelona 08036, Spain.
Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a disorder mediated by autoantibodies against the GluN1 subunit of NMDAR. It occurs with severe neuropsychiatric symptoms that often improve with immunotherapy. Clinical studies and animal models based on patients' antibody transfer or NMDAR immunization suggest that the autoantibodies play a major pathogenic role.
View Article and Find Full Text PDFLancet Glob Health
January 2025
Centre for Neonatal and Paediatric Infection and Vaccine Institute, City St George's, University of London, London, UK; Makerere University-Johns Hopkins University Research Collaboration, Kampala, Uganda; UK Health Security Agency, Salisbury, UK.
J Biol Chem
December 2024
Institute of Biomedicine, University of Turku, Turku, Finland.
Enzyme promiscuity is the ability of an enzyme to catalyze an unexpected side reaction in addition to its main reaction. Here, we describe a biocatalytic process to produce non-hydrolyzable NAD+ analogs based on the ADP-ribosyltransferase (ART) activity of pertussis toxin PtxS1 subunit. First, in identical manner to normal catalysis, PtxS1 activates NAD+ to form the reactive oxocarbenium cation.
View Article and Find Full Text PDFACS Pharmacol Transl Sci
December 2024
Synovo GmbH, Paul-Ehrlich-Straße 15, 72076 Tübingen, Germany.
Background: Myelin oligodendrocyte glycoprotein 35-55 (MOG)-peptide induced experimental autoimmune encephalomyelitis (EAE) is a model for inflammation of the brain and spinal cord. However, its severity and incidence vary within and between laboratories. Severe scores can lead to premature termination and are both unnecessary for readouts and detrimental to animal welfare.
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