摘要目的 探讨新生大鼠坏死性小肠结肠炎(necrotizing enterocolitis,NEC)发病过程中肠型脂肪酸结合蛋白(intestinal fatty acid-binding protein,I-FABP)表达变化及意义.方法 新生SD大鼠24只随机分为对照组、NEC模型1组、NEC模型2组、NEC模型3组,每组6只.新生大鼠生后48 h内与母鼠同笼,由母鼠喂养.48 h后NEC模型组通过人工喂养+缺氧+冷刺激+脂多糖灌胃(10 mg/kg)建立NEC模型,并分别在造模结束后1、2、3 d空腹处死;对照组不干预,在NEC模型组造模结束后3 d空腹处死.取各组大鼠回盲部肠管固定或冻存,采用苏木精-伊红染色观察小肠组织病理改变并评分;应用实时定量聚合酶链反应法检测大鼠肠道I-FABP mRNA转录水平,酶联免疫吸附法检测大鼠肠道I-FABP蛋白表达水平.结果 NEC模型1组、NEC模型2组、NEC模型3组造模结束后体重均明显低于对照组,差异有统计学意义(P<0.001);肠组织病理评分分别为2(2,3)分、3(2,3)分、4(3,4)分,与对照组相比明显增高,差异有统计学意义(P<0.05).NEC模型1组、NEC模型2组、NEC模型3组大鼠肠道I-FABP mRNA转录水平分别为2.69±0.27、2.12±0.09、3.18±0.22,蛋白表达水平分别为363.7±11.4、321.7±45.8、432.3±50.3,均显著高于对照组(1.00±0.02和134.2±24.0),差异有统计学意义(P<0.05).结论 I-FABP是肠道缺血性损伤的有效标志物,检测I-FABP可能有助于新生儿NEC的早期诊断.

abstractsObjective To study the expression of intestinal intestinal fatty acid-binding protein (I-FABP) and its clinical significance in an experimental model of necrotizing enterocolitis (NEC) in neonatal rats. Method Twenty-four neonatal Sprague-Dawley (SD) rats were randomly assigned into 4 groups at 48 h after birth (6 rats in each group):group A (control group), group B (NEC group-1), group C (NEC group-2), and group D (NEC group-3). The neonatal rats were fed by the mother rats in the same cage within 48 h after birth. After 48 h, the NEC group received artificial feeding, hypoxia, cold stimulation and lipopolysaccharide (LPS) gavage (10 mg/kg). NEC group-1, 2 and 3 were sacrificed on an empty stomach at 1, 2 and 3 d after the modeling. The control group was sacrificed on an empty stomach 3 d after the modeling without special treatment. Intestinal tissue were obtained from each rats. The histological changes of ileal tissues were studied using hematoxylin-eosin (HE) staining. The expressions of intestinal I-FABP were detected using RT-PCR and ELISA methods. Result Compared with the control group, body weight of rats in NEC group-1, 2 and 3 were lower, and pathology scores in these three groups were higher (P<0.05). The levels of intestinal I-FABP mRNA in NEC group-1, NEC group-2 and NEC group-3 were 2.69±0.27, 2.12±0.09, 3.18± 0.22, respectively. The protein expression levels were 363.7 ± 11.4, 321.7 ± 45.8, 432.3 ± 50.3, respectively. The mRNA and protein levels were all significantly higher than the control group (mRNA: 1.00 ± 0.02, protein: 134.2 ± 24.0, P<0.05). Conclusion I-FABP was a useful marker for ischemic injury to the intestine. These findings may contribute to a better diagnosis of NEC in newborns.