猪苓多糖对小鼠腹腔巨噬细胞一氧化氮生成、iNOS活性和细胞内还原型谷胱甘肽含量的影响

目的 :观察猪苓多糖 (PPS)对小鼠腹腔巨噬细胞一氧化氮 (NO)生成及其免疫调节作用和抗肿瘤作用机制。方法 :采用Griess反应、荧光法和DTNB比色法分别测定不同剂量的PPS作用小鼠腹腔巨噬细胞的NO生成量、诱导型一氧化氮合酶 (iNOS)活性及细胞内还原性谷胱甘肽 (GSH)含量的变化。结果 :PPS能使小鼠腹腔巨噬细胞NO生成增加 ,i NOS活性增高 ,并呈作用剂量依赖关系 ;PPS在刺激小鼠腹腔巨噬细胞NO合成同时 ,伴有细胞内GSH水平的降低 ,呈负相关 (P <0 .0 5 )。结论 :PPS能提高小鼠腹腔巨噬细胞iNOS活性 ,增加NO合成 ,消耗细胞内的GSH。提示细胞内GSH可能起到调节巨噬细胞NO生成和保护宿主细胞免受NO介导的细胞毒作用

Effect of polyporus polysaccharide on NO production,iNOS activity and intracellular reduced glutathione level from peritoneal macrophages of mice

Objective:To investigate the effect of polyporus polysaccharide (PPS) on nitric oxide (NO)production from peritoneal macrophages of mice and its immunoregulatory and antineoplastic mechanism.Methods:NO output,iNOS(inducible nitric oxide synthase)activity and reduced glutathione(GSH)level were determined by Griess reaction,fluorimetry and DTNB colorimetry respectively.Results:PPS treatment resulted in a dose dependent increase of NO production and iNOS activity.There was a negative correlation between the increase of NO output and decrease of GSH concentration( P< 0.05).Conclusion:PPS is able to induce iNOS activity and to stimulate NO synthesis,which is associated with the consumption of intracellular GSH.Intracellular GSH could regulate NO synthesis of macrophages and protect host cells from NO mediated cytotoxicity.