Differential expression of arginase and iNOS in the lung in sepsis
Differential expression of arginase and iNOS in the lung in sepsis
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DOI：
10.3109/01902149809041533
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发表时间：
1998-05-01
影响因子：
1.7
通讯作者：
Huang, YCT
中科院分区：
文献类型：
--
作者：
Carraway, MS;Piantadosi, CA;Huang, YCT
L-精氨酸的主要代谢归宿是通过一氧化氮合酶（NOS）转化为L-瓜氨酸，通过精氨酸酶转化为L-鸟氨酸。在肺中，精氨酸利用增加后，诱导型一氧化氮合酶（iNOS）在炎症期间表达。然而，在正常肺和脓毒症后，其表达，以及其与iNOS的潜在关系，是未知的。由于肺激酶和iNOS共享底物L-精氨酸，因此我检验了以下假设：在脓毒症中肺激酶将与iNOS共同诱导，并且其细胞分布将与肺中iNOS的分布相关。手术后6或16小时，从盲肠结扎和穿孔（CLP）和假手术（S）大鼠中收获肺。肺湿干重比、髓过氧化物酶含量和脂质过氧化产物作为肺损伤的指标。Western印迹分析进行了多克隆抗体对两种亚型的大鼠NOS（I和II）和iNOS。CLP和S动物的其他肺进行膨胀固定，用于使用相同抗体的免疫组织化学。我们通过Western印迹发现，在39 kDa的酶II是存在于正常大鼠肺中的主要异构体。酶分布于肺泡和支气管上皮细胞、内皮细胞和肺泡巨噬细胞。CLP后16小时，大鼠肺中几乎检测不到酶II。而在正常肺组织中，iNOS可通过Western blot或免疫组化检测到。CLP后，在类似细胞类型中发现iNOS的强表达，以抑制酶II。这些数据表明，当iNOS被脓毒症的应答上调时，大鼠肺中的iNOS II的组成型表达丧失。
The primary metabolic fates of L-arginine are conversion to L-citrulline by nitric oxide synthase (NOS) and to L-ornithine by arginase. In the lung, arginine utilization is increased after the inducible form of NOS (iNOS) is expressed during inflammation. The expression of arginase in normal lung and after sepsis, and its potential relationships with iNOS, however, are not known. Since arginase and iNOS share the substrate L-arginine, me tested the hypothesis that lung arginase would be co-induced with iNos in sepsis and its cellular distribution would be related to that of iNOS in the lung. Lungs from cecal ligation and puncture (CLP) and sham-operated (S) rats were harvested 6 or 16 hours after the procedures. Lung wet-to-dry weight ratio, myeloperoxidase content, and lipid peroxidation products were measured as indices of lung injury. Western blot analyses were performed with polyclonal antibodies against two isoforms of rat arginase (I and II) and iNOS. Additional lungs from CLP and S animals were inflation-fixed for immunohistochemistry using the same antibodies. We found by Western blot that arginase II at 39 kDa was the main isoform present in normal rat lung. The enzyme teas distributed diffusely in alveolar and bronchial epithelial cells, endothelial cells, and alveolar macrophages. After CLP, arginase II was almost undetectable in rat lungs at 16 hours. In contrast, in normal lung, the iNOS was Rot detectable by Western blot or immunohistochemistry. After CLP, strong expression of iNOS was found in similar cell types to arginase II. these data demonstrate loss of constitutive expression of arginase II in rat lung as iNOS is upregulated by the response to sepsis.