内毒素调节血细胞释放β-葡萄糖苷酸酶的实验研究

Experimental research of blood cell releasing β-glucuronidase regulated by endotoxin

目的研究内毒素可否增加小鼠血清β-葡萄糖苷酸酶(β-GD)的活性,以及内毒素对正常人外周血单核细胞(PBMC)产生β-葡萄糖苷酸酶的影响。方法按每公斤体重5mg内毒素(实验组)和生理盐水(对照组)腹腔注射BALB/c小鼠,并于注射后的1/2、2、4和24h取血液抗凝离心,上清液冻存;以1μg/mL内毒素(实验组)和生理盐水(对照组)刺激体外培养的外周血单核细胞,并分别于培养的2、4、8、12和24h取上清液;采用酶促动力学方法于pH值4.5条件下检测上清液β-GD活性。结果与对照组BALB/c小鼠比较,腹腔注射内毒素1/2、2和4小时后,血清β-葡萄糖苷酸酶活性显著增高,依次为(2.14±1.46),(3.96±0.88),(4.40±0.55),(5.65±0.58)Fishman单位,t值分别为2.548、2.896和4.474,P<0.05。正常人PBMC在与LPS共培养的4、8、12和24h,实验组β-GD活性显著高于对照组,分别为(1633.3±65.0)和(1106.7±48.6),(1926.0±147.1)和(1067.7±133.1),(1743.3±66.8)和(1016.7±147.7),(1553.7±79.6)和(1193.3±90.2)Fishman单位/106PBMC,t值分别为14.5、9.6、10.0和6.7,P<0.05。结论BALB/c小鼠经过腹腔注射内毒素后,其血清中β-GD的酶活性具有显著性增加。内毒素还可以增加正常人PBMC释放β-GD,此途径可能是内毒素参与胆石症发病的又一个机制。

[Objective] To investigate the effect of endotoxin on the the activity of serumal β-glucuronldase（β- GD） in mice, and the effect of endotoxin on β-GD activity in human peripheral blood mononuclear cells （PBMC）. [Methods] Twenty-three BALB/c mice were randomly divided into control group （injection of Saline without endotoxin） and LPS group（received dosage of endotoxin was 5 mg/kg）. In the LPS group, after the injection of endotoxin, the mice were put to death at the 1/2, 2, 4, 24 hour. Blood was taken to antlcoagulate and centrlfugate, and the activity of serumal β-glucuronidase was detected by enzyme kinetics method; 1μg/mL of LPS or Saline （as control group） was applied to stimulate human PBMC, and β-GD activity in the medium was detected by the same method at the 4 th, 8 th, 12 th and 24 th hour. [Results] In LPS 1/2, 2 and 4 h group of mice, the activity [（3.96±0.88）, （4.40±0.55）, （5.65 ±0.58） Fishman Unit, respectively] was all significantly higher than in the control＇s （P 〈0.05）. While there was no significant difference between the LPS 24 h group [（3.85±1.11） Fishman Unit] and the control group. In human PBMC, the β-GD activity in the LPS groups was significantly higher after cultured for 4, 8, 12 and 24 hours than in the control＇s [（1633.3±65.0） vs （1106.7±48.6）, （1926.0±147.1） vs （1067.7±133.1）, （1743.3±66.8） vs （1016.7±147.7）, （1553.7±79.6） vs （1193.3±90.2） Fishman unit/106 PBMC, t value were 14.5, 9.6, 10.0 and 6.7, respectively, P 〈0.05].[Conclusion] LPS not only increase the serumal activity of β-glucuronidase of BALB/c mice,but also increase PBMC to produce more human β-GD, which may be another mechanism of LPS involving in the pathogenesis of cholelithiasis.