谷氨酰胺对内毒素诱导幼鼠肠损伤的保护作用

Proective effects of glutamine on intestinal injury of infant rats induced by endotoxin.

目的探讨内毒素(LPS)致幼鼠肠损伤及谷氨酰胺(glutam ine G ln)的保护作用。方法10日龄W istar幼鼠共72只,分为A组:生理盐水组,B组:内毒素组,C组:内毒素+谷氨酰胺组。以EcoliO55:B5(1m l/kg)、生理盐水(1m l/kg)谷氨酰胺(10m l/kg)腹腔注射,给药后2、6、24h处死动物,留取肠组织,免疫组化检测肠组织肿瘤坏死因子-α(tumor necrosis factor-,αTNF-α)蛋白含量,生化法检测肠组织MDA含量,同时作电镜观测肠组织超微结构变化。结果B组TNF-α积分光密度、MDA含量明显高于A组,以LPS作用后6h达高峰(37247.64±3168.80 vs 6191.02±482.32,P<0.01;7.601±1.144 vs 5.014±0.741,P<0.01)。C组TNF-α、MDA含量较B组明显降低,其中各时间点TNF-α较B组下降,但仍高于A组,P<0.01;24h C组MDA含量较B组下降,P<0.01;但较A组无差异,P>0.05。B组肠组织超微结构变化明显,C组肠组织超微结构变化较B组不同程度减轻。结论LPS可致幼鼠肠损伤,G ln对肠损伤有保护作用。

Objectives： To study the effects of LPS to intestines of infant rats and testify the protective effects of glutamine. Methods： 10 -day -old Wistar infant rats were divided by groups A, B, C. Group A were served as the normal control group and injected with normal saline （1ml/kg） intraperioneally. Group B and C were treated with LPS （1ml/kg） and LPS （1ml/kg） ± Gln （10ml/kg） intraperioneal respectively. Followed by LPS administration, intestinal tissues were collected at 2, 6, and 24h to examine TNF - α expression, MDA productions and intestinal histological changes. Results ： It can be seen the TNF - α expression in epithelial cells of intestines. The IODT of TNF - α and MDA contents were significantly increased in group B and reached the maximum 6h after LPS administration （37247.64 ± 3168. 80 vs 6191.02 ±482. 32, P 〈 0.01 ; 7. 601 ± 1. 144 vs 5. 014 ± 0. 741, P 〈 0. 01 ）. Contrasted with group B, The expression of TNF - α of group C were decreased and still sustained high level at every time, P 〈 0.01. Whereas the contents of MDA were decreased than group B （ P 〈0. 01） but had no discrepancy with group A （ P 〉0.05） at 24h group. The ultra structure of intestinal tissues had obvious changes in group B, which improved in group C. Conclusion： LPS can induce the intestinal injuries in infant rats and glutamine have marked protectively effects.