Production of Nitric Oxide by Activated Microglial Cells Is Inhibited by Taurine Chloramine
Microglia are considered to be brain resident macrophages and along with astrocytes are the major immunoresponsive cells in the CNS1,2. When activated by bacterial endotoxin or cytokines, microglia respond rapidly by proliferating, changing morphology, and by producing proinflammatory cytokines and NO2-4. Although transient activation of microglia contributes to brain repair processes, chronic activation as occurs in CNS viral infections5, AIDS dementia complex6, Alzheimer’s disease7, multiple sclerosis8,9, traumatic injury, and stroke, leads to neuronal cell death as a result of inflammation and oxidative stress2,4,10 Production of nitric oxide is of particular importance in the pathology of several CNS disorders because of the toxicity of its byproducts, e.g. peroxynitrite. The increased production of NO by activated microglia results primarily from increased expression of the iNOS gene. The therapeutic potential of downregulating activation of microglia and/or production of NO may be of significant clinical value in developing strategies for treatment of neurodegeneative diseases.
KeywordsNitric Oxide Microglial Cell iNOS mRNA iNOS Gene Murine Microglial Cell
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