Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0037116 (silicosis)
 1,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Silicosis was produced experimentally in rats by single intratracheal injections of various doses of SiO2 dust. The weight of the lungs as well as the contents of total nitrogen, collagen, nucleic acids (especially RNA), and lipids increased in accordance with the dose and the time interval. Fibrogenic stimulation in vitro was shown by the supernatant of the homogenized lung in the incorporation of proline into incubated granulation tissue or lung fibroblasts. The fibrogenic factor-activity depended more on the time interval after the injection than on the SiO2 dose. Electrophoresis of the soluble proteins in the silicotic rat lungs showed a protein of 16,000 Da, which was dependent on the time interval following SiO2 administration as well as on the dose itself, and which originated from macrophages. This protein was purified by repeated gel-filtration chromatography. It stimulated collagen synthesis in granulation-tissue cells at a concentration of about 10(-10) M in a dose-dependent way. It was acidic by amino acid composition but differed from calmodulin which also increased collagen synthesis in granulation-tissue cells in vitro. The ability of non-fractionated macrophage preparations to stimulate the incorporation of proline into collagen correlated inversely with the gross alkaline RNase activity.
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PMID:Isolation of silica-dependent protein from rat lung with special reference to development of fibrosis. 254 36

Antiserum against the fibrogenesis controlling macrophage RNase was produced in rabbits. It caused an inhibition of 57% in the RNase activity in vitro. A distinct dose-response relationship was observed in the inhibiting effect of the antiserum on RNase-induced 3H-thymidine incorporation into cultured granulation-tissue fibroblasts. The antifibrogenic properties of the antiserum were also tested in vivo. Rat lungs were made silicotic by intratracheal administration of SiO2. This treatment clearly increased the following parameters: wet weight, DNA, RNA, nitrogen and hydroxyproline content of the lung tissue, and protein concentration, RNase activity, and cell count of the lung lavage fluid. Also, the RNase activity of the lavage fluid cells was increased. Periodical intratracheal administration of the anti-RNase antiserum, optimally at 1:1,000 dilution, decreased the DNA, RNA, and hydroxyproline content of the lung tissue, each by about 30%. The RNase activity of lavage fluid cells was decreased by about 60%. In conclusion the antiserum had no effect on the normal lungs, but it significantly suppressed the development of silicosis.
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PMID:Antifibrogenic effects of antiserum against the macrophage RNase. 683 34