预防性应用天然蒙脱石对新生大鼠坏死性小肠结肠炎肠损伤的保护作用  

Protective effect of smectite powder on necrotizing enterocolitis in neonatal rat model

作　　者：吴斌[1] 陈兢芳[1] 卓玲[1] 杨燕珍[1] 董海英[1] 

机构地区：[1]福建医科大学附属第一医院儿科,福州350005

出　　处：《中华围产医学杂志》2010年第1期50-54,共5页Chinese Journal of Perinatal Medicine

摘　　要：目的探讨预防性应用天然蒙脱石对新生大鼠坏死性小肠结肠炎（necrotizing enterocolitis，NEC）模型肠损伤的保护作用及可能机制。方法按析因设计，32只新生SD大鼠随机分成4组，每组8只。A组为NEC模型，出生48h起给予天然蒙脱石0．6g／（kg·d）灌胃；B组为NEC模型，未添加天然蒙脱石；C组为对照，未添加天然蒙脱石；D组为对照，出生48h起给予天然蒙脱石0．6g／（kg·d）灌胃。SD新生大鼠出生后48h开始采用鼠配方奶喂养，100％氮气90s，4℃10min，每天2次，连续3d，建立新生大鼠NEC模型。A、B组在造模结束后24h和C、D组新生大鼠空腹断头处死，留取十二指肠下端至直肠上端肠管进行肠细胞凋亡率检测（流式细胞仪）、电镜观察和血小板活化因子（platelet—actvating factor，PAF）、肿瘤坏死因子-α（tumor necrosis factor—α，TNF-α）含量（ELISA法）检测。所有新生大鼠均留取回盲部近端肠管进行肠组织损伤评分。结果造模后，A、B组新生鼠相继出现腹泻、腹胀、萎靡、活动减少，生长减慢；透射电镜显示肠黏膜出现大量凋亡细胞，形成凋亡小体，A组程度较轻。A、B、C和D组肠组织损伤评分分别为1．42±0．36、3．54±0．50、0．13±0．17和0．17±0．18，肠细胞凋亡率为（11．6±4．6）％、（27．6±9．9）％、（4．8±2．9）％和（3．6±3．8）％；与B组相比，A组肠组织损伤评分和肠细胞凋亡率明显降低，但仍高于C、D两组（P均〈0．01）。A、B、C和D组肠组织PAF含量（单位为pg／mg prot）分别为385．0±308．0、1663．2±576．1、40．8±40．4和37．1±33．1；TNF-α含量（单位为pg／mgprot）为46．4±15．1、258．1±281．7、13．2±12．2和12．4±8．8。B组肠组织PAF、TNF-α含量明显高于C、D组；与B组相比，A组肠组织PAF、TNF-α含量明显降低（P均〈0．01）。肠组织损伤评分、肠细胞凋亡率及肠组织PAObjective To explore the protective effects and the mechanism of smectite powder in neerotizing enterocolitis（NEC） model of neonatal SD rat. Methods Thirty-two neonatal SD rats were divided into 4 groups （A, B, C and D, 8 rats in each group）. Rats in group A and B were NEC models established by exposure to hypoxia （100% N2） for 90 s and 4 ℃ for 10 rain, twice a day for 3 consecutive days. Rats in group A received smectite powder 0.6 g/ （kg · d） and those in group B did not. Rats in groups C and D served as control groups with those in group D received smectite powder 0.6 g/（kg · d） and those in group C did not. The rats were sacrificed on day 4 and intestines were collected. The apoptosis ratio of intestinal cells was determined with flow cytometry and the morphological changes in intestinal mucosa were observed under light and electron microscopes, and the content of PAF, TNF-α were tested by ELISA. Results The rats in group A and B had diarrhea, abdominal distention, slow growth and development, less activity, and the apoptosis cells and apoptic body were observed in their intestine mucosa. As compared with group B, after given smectite powder, symptoms in the rats of group A were remarkably relieved. The scores ofhistological evaluation in group A, B, C and D were 1.42±0.36, 3.54±0.50, 0.13±0.17 and 0.17 ±0.18, respectively, and the apoptosis ratios of intestinal cells were （11.6 ± 4.6） %, （27.6 ±9.9） %, （4.8 ±2.9） % and （3.6 ±3.8） %, respectively. Compared with the histopatholigical score and the apoptosis ratio of intestinal cells of group B, those of group A reduced, but remained significantly higher than those of group C and D. In group A, B, C and D, the contents of PAF in intestinal tissue （expressed as pg/mg prot） were 385.0±308.0, 1663.2±576.1, 40.8±40.4 and 37. 1±33.1, and TNF-α （expressed as pg/mg prot） were 46.4±15.1, 258.1±281.7, 13.2±12.2 and 12.4±8.8, respectively. Compared with group B, those in group A reduced significantly, whil

关 键 词：小肠结肠炎 坏死性 动物 新生 大鼠 硅酸盐类 细胞凋亡 

分 类 号：R722.1[医药卫生—儿科]