Mayo K, Held M, Wadström T, Mégraud F
Laboratoire de Bactériologie-Enfants, Hopital Pellegrin, Bordeaux, France.
Eur J Gastroenterol Hepatol. 1997 May;9(5):457-61. doi: 10.1097/00042737-199705000-00009.
To determine if the ammonia produced by Helicobacter pylori affects the phagocytic ability of human polymorphonuclear leucocytes as measured by the oxidative burst.
Interactions between opsonized urease-positive and -negative strains of H. pylori with polymorphonuclear leucocytes were studied in two series of experiments. In the first series of experiments, concentrations from 0 to 50 mM of NH4Cl were added to polymorphonuclear leucocytes. In the second series of experiments, bacteria were pre-incubated for 1 h with urea (0 to 50 mM) before addition of phagocytes. Luminol-dependent chemiluminescence was measured every 5 min over a 50-min period. The pH was verified in each treatment.
Inhibition of chemiluminescence, increasing with concentration, was noted in all treatments when NH4Cl was added. When urea was added to urease-positive strains, chemiluminescence was significantly reduced when compared to the urease-negative strain and the zymosan control. This effect could not be attributed to a change in pH in the experiments using NH4Cl or urea at a concentration of 5 mM and 10 mM.
Ammonia generated by H. pylori may contribute to the decreased activity of polymorphonuclear leucocytes in vivo.
通过氧化爆发来测定幽门螺杆菌产生的氨是否会影响人多形核白细胞的吞噬能力。
在两个系列的实验中研究了调理过的幽门螺杆菌尿素酶阳性和阴性菌株与多形核白细胞之间的相互作用。在第一个系列实验中，向多形核白细胞中添加浓度为0至50 mM的氯化铵。在第二个系列实验中，在添加吞噬细胞之前，将细菌与尿素（0至50 mM）预孵育1小时。在50分钟的时间内每隔5分钟测量一次鲁米诺依赖性化学发光。对每种处理的pH值进行了验证。
添加氯化铵时，在所有处理中均观察到化学发光的抑制，且随浓度增加。当向尿素酶阳性菌株中添加尿素时，与尿素酶阴性菌株和酵母聚糖对照相比，化学发光显著降低。在使用浓度为5 mM和10 mM的氯化铵或尿素的实验中，这种效应不能归因于pH值的变化。
幽门螺杆菌产生的氨可能导致体内多形核白细胞活性降低。
Zotero 插件