Inducible nitric oxide synthase mRNA and activity in glomerular mesangial cells.
Inducible nitric oxide synthase mRNA and activity in glomerular mesangial cells.
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肾小球系膜细胞中诱导型一氧化氮合酶 mRNA 和活性。
DOI：
10.1038/ki.1994.321
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发表时间：
1994
影响因子：
19.6
通讯作者：
Rosenberg,ME
中科院分区：
文献类型：
--
作者：
Shultz,PJ;Archer,SL;Rosenberg,ME
肾小球系膜细胞诱导型一氧化氮合酶mRNA及其活性。以往的研究表明，肾小球系膜细胞产生一氧化氮（NO），使用的NO分解产物，NO2-和NO3-的测量。我们现在已经直接测量NO在大鼠肾小球系膜细胞培养物上方的顶部空间，使用化学发光分析仪。此外，我们研究了系膜细胞RNA诱导型一氧化氮合酶（iNOS）。我们发现在未受刺激的系膜细胞中，在顶空或iNOSmRNA中没有检测到NO。然而，在与LPS（10 μg/ml）孵育4小时后，iNOS mRNA是明显的，并且在6小时后，检测到NO显著增加。这两个参数持续增加至少24小时。与LPS孵育24小时后，还检测到培养基中的NO2-/NO3-和系膜细胞中的cGMP的显著增加。放线菌素D和地塞米松可明显抑制LPS诱导的iNOS mRNA的表达，并抑制培养液中NO2-/NO3-的积累。放线菌酮可显著抑制LPS诱导的细胞培养液中NO2-/NO3-的含量，但对LPS诱导的iNOSmRNA表达无明显影响。我们的结论是，大鼠肾小球系膜细胞具有诱导型一氧化氮合酶，与巨噬细胞中所描述的活性和调节相似。此外，我们通过直接测量NO及其分解产物NO2-和NO3-来证明这种酶的活性。我们认为，肾小球系膜细胞产生NO可能发生，即使巨噬细胞浸润是不存在的，并可能，从而调节肾小球和肾小管内的肾脏功能。
Inducible nitric oxide synthase mRNA and activity in glomerular mesangial cells. Previous studies have suggested that glomerular mesangial cells produce nitric oxide (NO), using measurements of the NO decomposition products, NO2-and NO3-. We have now directly measured NO in the headspace above rat mesangial cell cultures, using a chemiluminescence analyzer. In addition, we examined mesangial cell RNA for inducible NO synthase (iNOS). We found no detectable NO in the headspace or iNOS mRNA in unstimulated mesangial cells. However, after four hours of incubation with LPS (10 µg/ml), iNOS mRNA was apparent and after six hours, significant increases in NO were detected. Both of these parameters continued to increase for at least 24 hours. Significant increases in NO2-/NO3-in the media and cGMP in the mesangial cells were also detected after 24 hours of incubation with LPS. The induction of iNOS mRNA by LPS was markedly inhibited by actinomycin D and dexamethasone, as was the accumulation of NO2-/NO3-in the media. Cycloheximide significantly inhibited NO2-/NO3-in the media of LPS-treated cells, but had little effect on induction of iNOS mRNA by LPS. We conclude that rat mesangial cells possess an iNOS, with activity and regulation similar to that described in macrophages. Furthermore, we demonstrate the activity of this enzyme by direct measurement of NO and its decomposition products, NO2-and NO3-. We suggest that production of NO by glomerular mesangial cells could occur, even when macrophage infiltration is not present, and could, thereby, modulate glomerular and tubular functions within the kidney.