人体白细胞NADPHoxidase的定位及多霉黏毒的抑制作用

Localization of NADPH Oxidase in Human Leukocytes and the Inhibitory Effect of Gliotoxin on It

目的 研究还原型尼克安腺嘌呤二核苷酸氧化酶 (reducednicotinamideadeninedinucleotidephosphateoxidase,NADPHoxidase)在人体白细胞中的细胞化学定及多霉黏毒 (gliotoxin)对其活性的抑制作用。方法 用phorbol 12 myristate 13 acetate(PMA)和 gliotoxin对白细胞预处理 ,然后用Ce3 + 作捕促剂检测活性氧 ,作为电镜下NADPHoxidase的活性标志。结果 PMA组 :在白细胞内大小形态各异的囊泡膜腔面有很多显示NADPHoxidase活性的致密颗粒。PMA +gliotoxin组 :嗜中性和嗜酸性白细胞内显示该酶活性的颗粒都明显减少 ,但后者减少程度较轻。结论 白细胞经刺激后NADPHoxidase位于细胞内囊泡膜的腔面 ,参与机体的防御机能。gliotoxin对NADPHoxidase产生的过量O-2 有明显的抑制作用 ,在抗氧化方面有一定的应用前景。

Purpose: To study the cytochemical localization of reduced nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) in leukocytes and the inhibitory effect of gliotoxin on its activity. Methods: Human leukocytes were preincubated in the media with phorbol 12-myristate 13-acetate (PMA) or with PMA plus gliotoxin. The reactive oxygen species, which are the activity products of NADPH oxidase, were measured cytoc-hemical by electron microscopy using Ce3+ as the capture. Results: In the PMA-treated group, many vesicles(including endosomes and small vesicles) in different shapes and sizes were observed in the leukocytes. A lot of dense particles denoting the NADPH oxidase activity were attached to the luminal face of the vesicle membrane. In the PMA + gliotoxin group, the dense particles decreased prominently both in neutrophils and in eosinophils, but, the dec-rease was less in the latter. Conclusions: NADPH oxidase locallized on the luminal face of vesicle membrane after leukocytes activation is beneficial to host defense mechanismagainst phagocytic organism. Gliotoxin has an inhibitory effect on the O z- overproduction of NADPH oxidase.