肠三叶因子对新生鼠坏死性小肠结肠炎模型Caspase-9表达的影响

Influence of Intestinal Trefoil Factor on Caspase-9 in Neonatal Rats with Necrotizing Enterocolitis

目的分析肠三叶因子(ITF)对坏死性小肠结肠炎(NEC)新生鼠肠黏膜组织Caspase-9表达的影响,探讨ITF对NEC的保护机制。方法新生鼠30只随机分为正常对照组、NEC组及ITF组,每组10只。正常对照组不作处理;NEC组建立NEC模型后予腹腔注射9g/L盐水0.2mL;ITF组建立NEC模型后予腹腔注射ITF0.2mg(即0.2mL)。取其近回盲段肠道组织1～2cm,立即固定于40g/L甲醛中,石蜡包埋,切片,HE染色和组织病理学检查,其他肠道组织制备组织匀浆,取上清液利用分光光度法检测Caspase-9水平。结果NEC组新生鼠组织匀浆Caspase-9水平为(23.37±2.36)U,较正常对照组[(9.77±2.21)U]及ITF组[(10.99±2.05)U]均显著增高(q=13.60,12.37Pa<0.05),正常对照组与ITF组间比较无显著性差异(q=1.22P>0.05)。病理切片HE染色示NEC组肠壁损伤轻重不一,可见全肠黏膜绒毛坏死,病理评分中位积分为3分;ITF组肠上皮细胞少量脱落,顶端绒毛坏死,病理评分中位积分为1分。结论腹腔注射ITF可减轻NEC后新生鼠的肠道损伤,ITF可能通过降低Caspase-9水平保护NEC新生鼠肠道。

Objective To analyze the influence of intestinal trefoil factor （ITF） on Caspase -9 in neonatal rats with necrotizing enteroeolitis（NEC） ,and to discuss the protective maehanism of ITF on NEC. Methods Thirty neonatal rats were divided randomly into normal control group, NEC group and ITF group. NEC group were injected intraperitoneally normal saline 0.2 mL after NEC model were established, ITF group were injected intraperitoneally ITF 0.2 mg after NEC model were established. On the 4th day, all subjects were put to death. Intestinal tissue within the boundary of ileum and cecum were obtained to observe histological changes. Other intestinal tissue were treated into homogenate. After the homogenate was centrifuged, supernates were used to test the density of Caspase - 9 by spectrophotometry. Results The density of Caspase - 9 in normal control group [ （ 9. 77 ± 2.21 ） u ] and ITF group [ （ 10.99 ±2.05 ） U ] were significantly lower than that in NEC group [ （23.37 ±2.36 ） U ] （ q = 13.60,12.37 Pa 〈 0.05 ） ; and there was no difference between normal control group and ITF group （q = 1.22 P 〉 0. 05 ）. The pathological lesions indicated that intestinal tissue necrosis was severe in NEC group, which was graded as 3 scores,but obviously lessen in ITF group,which was graded as 1 score,with ITF interfering. Conclusions Intestinal injury is ameliorated after ITF are injected intraperitoneally, ITF may protect the intestinal by reducing the level of Caspase - 9.