0199

Effect of glycine on endotoxin - induced rat model of necrotizing enterocolitis

Liu G-S, Kang J-L, Guan J-B, et al.

Hospital Jinan University, Guangzhou, China

 

Objective: Endotoxin can induce necrotizing enterocolitis (NEC). Tumor necrosis factor-α (TNF-α) and nitric oxide (NO) play a pivotal role in pathogenesis of NEC. The amino acid glycine has been shown to protect against endotoxin shock in the rats by inhibiting TNF-α and NO production. In the current study we investigated the effect of glycine on endotoxin- induced rat model of NEC.

Methods: In the study group twenty anesthetized and artificially ventilated rats received 1mg/kg glycine (20% injection). five minutes later, the rats were treated with 2mg/kg endotoxin (lipopolysaccharide, LPS).in the control group twenty anesthelized and artificially ventilated rats received only LPS. In all animals, FiO2 was reduced after 90 min from 0.21 to 0.05 and ventilation continued until 180 min or death. At the end of the experiment the samples of blood and intestine were obtained immediately. Serum TNF-α was measured with ELISA.Serum NO was determined by nitrate reductase. The histopathology of the necrotic leisions were categoried into four classes according to the degree of severity: gradefocal mild injury confined to villous tips;grade , partial loss of villi; grade, necrosis extending to submucosa; grade , transmural necrosis.

Result: The survival time (159.2522.78 VS 138.7519.05min) was shorter in the control group (P<0.01). The intestinal injury of the study group was markedly improved (P<0.01). The levels of TNF-αand NO in serum(220.2390.35 VS 120.747.22pg/ml; 211.6166.37 VS 152.4964.19μmol/L) decreased significantly in animals treated with glycine (P<0.01; P<0.05).

Conclusion: Our results of longer survival time and milder intestinal injury in glycine treated rats showed that glycine may protect against LPS-induced NEC by inhabiting TNF-αand NO production.