脂多糖联合人工喂养诱导新生大鼠坏死性小肠结肠炎模型的建立与评价  

Establishment and evaluation of necrotizing enterocolitis models induced by LPS combined with formula feeding in neonatal rats

作　　者：李美雪[1] 周伟[1] 吕回[1] 陶莉[1] 黄龙光[1] 袁伟明[1] 

机构地区：[1]广州医科大学附属广州市妇女儿童医疗中心新生儿科,广州510120

出　　处：《发育医学电子杂志》2014年第1期21-27,共7页Journal of Developmental Medicine (Electronic Version)

基　　金：广东省自然科学基金项目(8151012001000002)

摘　　要：目的探讨脂多糖(内毒素,LPS)联合人工喂养诱导新生大鼠坏死性小肠结肠炎(NEC)模型的方法并评价其效果。方法出生当日SD新生大鼠,按不同的造模方式随机分为9组(每组8只):A组大鼠人工喂养;B1、B2、B3、B4、B5、B6组为人工喂养+LPS灌胃,LPS的剂量分别为5、10、15、20、30、40 mg/kg,以筛选LPS诱导新生大鼠NEC模型的最佳剂量;C组大鼠采取鼠乳喂养+LPS(30 mg/kg)灌胃;D组大鼠为鼠乳喂养,作为正常对照组。每日定时称量体重。3天后禁食24小时取回肠末端组织HE染色,光镜下观察肠道组织病理损伤情况,并进行病理评分,评分≥2分确定为NEC。按B5组造模条件,重复两次,每次8只,分别为B5a、B5b组。结果 A、B4、B5、B6组新生大鼠均出现不同程度的活动减少,倦怠,进而可见腹胀及粪便颜色性状发生改变。实验结束A、B组体重不增或下降,C、D组体重增加,A、B组体重分别与D组比较,差异均有显著性(P<0.05)。各组病理评分分别为A组:1.78±0.52,B1组:1.76±0.32,B2组:1.83±0.1,B3组:1.87±0.33,B4组:2.16±0.11,B5组:3.34±0.37,B6组:3.78±0.51,C组:0.52±0.42,D组:0.3±0.48。B5a、B5b组评分分别为3.3±0.17、3.35±0.44。B5、B6模型组分别与对照组比较,差异均有显著性(P<0.05);模型组内B5、B6组分别与B1、B2、B3、B4组比较,差异均有显著性(P<0.05);B5、B6组分别与A组比较,差异均有显著性(P<0.05)。B5a、B5b分别与B5组比较,差异均无显著性(P>0.05)。B4、B5、B6组的NEC发生率分别为25%(2/8)、75%(6/8)和100%(8/8)。A、B1、B2、B3、C、D组的NEC发生率均为0。结论在LPS剂量为30 mg/kg时,联合人工喂养可诱导与人类新生儿NEC临床特征、病理改变基本一致的严重肠道损伤,且其发生率高,重复性好,特异性高,可用于新生儿NEC的研究。Objective To establish and evaluate the effect of the neonatal necrotizing enterocolitis (NEC) model induced by lipopolysaccharide (endotoxin, LPS) combined with formula feeding. Method According to different modeling methods, 0-day-postnatal SD rats were divided into 9 groups randomly, each group including 8 rats. Group A was given formula feeding alone; group B1, B2, B3, B4, B5 and B6 were given formula feeding and LPS intragastric administration, the dosages of LPS were respectively 5, 10, 15, 20, 30, 40 mg/kg in order to screen out the best one; group C was given breast feeding and LPS intragastric administration; group D was set up as control group and given breast feeding only. All rats were weighed every day at regular time. After 3 days feeding and fasting for 24 hours and then all the rats had been sacrificed. Terminal ileum were harvested and observed the intestinal histopathological damage by HE staining, and evaluated the ileal damage by pathological score. The rats with pathological score higher than two were defined as NEC. According to the modeling method of group B5, repeated twice, 8 rats each time, and divided into group B5a and B5b. Result Neonatal rats in group A, B4, B5 and B6 showed various degrees of physical inactivity, tiredness, and then abdominal distention and changes of stool’s color and character. On day 3, the weight of neonatal rats in group A and B had no increase or even loss, and group C and D had weight gain. The terminal weights and weight changes of group A and B were significantly different from that of Group C and D (P<0.05). The pathological score of every group were respectively: group A:1.78±0.52, group B1: 1.76±0.32, group B2: 1.83±0.1, group B3: 1.87±0.33, group B4: 2.16±0.11, group B5: 3.34±0.37, group B6: 3.78±0.51, group C: 0.52±0.42, group D: 0.3±0.48. There were significant differences between model groups B5, B6 and control group D (P<0.05). Among the model groups, the pathological scores of group B5, B6 were significantly higher than group B1, B2, B3

关 键 词：脂多糖 坏死性小肠结肠炎 大鼠 

分 类 号：R722.1[医药卫生—儿科]