Expression of Inducible Nitric-oxide Synthase and Intracellular Protein Tyrosine Nitration in Vascular Smooth Muscle Cells

摘要: A significant increase in the induction of inducible nitric-oxide synthase (iNOS) protein expression and levels nitrite plus nitrate was observed rat aortic smooth muscle cells (RASMCs) stably transfected with catalase (RASMC-2C2) as compared empty vector-transfected RASMC-V4 after exposure to cytokines lipopolysaccharide. The increased iNOS RASMC-2C2 associated a activation nuclear transcription factor κB, one transcriptional regulators expression. also accompanied by tyrosine nitration both cell types revealed immunocytochemical staining high pressure liquid chromatography on-line electrospray ionization tandem mass spectrometry. Nitrotyrosine formation inhibited 1400W, an inhibitor, 4-(2-aminoethyl) benzenesulfonyl fluoride, inhibitor NADPH oxidase, superoxide dismutase mimetic M40403, but not peroxidase 4-aminobenzoic hydrazide. Electron microscopy using affinity-purified anti-nitrotyrosine antibodies labeling at cytosolic side rough endoplasmic reticulum membranes, nucleus, occasionally mitochondria, consistently within fibrillar layer underneath plasma membrane. Collectively, data this model system indicate that hydrogen peroxide, inhibiting prevents expression, whereas contributes precise pattern intracellular nitration.