CAJ | 학술논문

目的观察急性坏死性胰腺炎(ANP)大鼠肠道超微结构及其通透性的变化,探讨褪黑素(MT)对肠道屏障功能(IBF)的影响.方法将72只SD大鼠随机分成ANP组、MT组、假手术组(SO组),各24只.ANP组和MT组大鼠采用胰胆管末端穿刺逆行注入5%牛磺胆酸钠制备ANP模型.MT组于制模前腹腔注射MT溶液.术后4、12、24、48 h处死动物,用ELISA法测血清肠脂肪酸结合蛋白(IFABP),光镜下观察末端回肠病理改变,电镜下观察回肠组织超微结构变化,TUNEL法观察肠上皮细胞凋亡情况.结果 SO组大鼠胰腺及回肠黏膜未见明显病理改变,回肠组织超微结构无明显变化,TUNEL法检查未见明显细胞凋亡;ANP组大鼠光镜下可见回肠柱状上皮细胞坏死、绒毛脱落,回肠超微结构异常最明显,上皮细胞微绒毛排列紊乱且短矮,TUNEL法提示回肠上皮凋亡细胞较多,以绒毛顶端为主;MT组大鼠病理改变、超微结构异常均较ANP组减轻,上皮凋亡细胞较ANP组减少.ANP组大鼠各时点血清IFABP水平较SO组显著升高,差异有统计学意义(P均＜0.05);而MT组大鼠各时点血清IFABP水平较ANP组显著下降,差异亦有统计学意义(P均＜0.05).结论 ANP可导致IBF障碍,肠上皮细胞有不同程度的坏死和凋亡.提示ANP发病早期肠道上皮细胞凋亡和增生之间失去平衡是IBF障碍的病理机制之一.予以MT干预,可以改善ANP发病后的肠道病理改变和肠道超微结构异常,其作用途径可能是通过抗氧化作用及抑制炎症反应,有待进一步的研究证实.
목적 관찰급성배사성이선염(ANP)대서장도초미결구급기통투성적변화,탐토퇴흑소(MT)대장도병장공능(IBF)적영향.방법 장72지SD대서수궤분성ANP조、MT조、가수술조(SO조),각24지.ANP조화MT조대서채용이담관말단천자역행주입5%우광담산납제비ANP모형.MT조우제모전복강주사MT용액.술후4、12、24、48 h처사동물,용ELISA법측혈청장지방산결합단백(IFABP),광경하관찰말단회장병리개변,전경하관찰회장조직초미결구변화,TUNEL법관찰장상피세포조망정황.결과 SO조대서이선급회장점막미견명현병리개변,회장조직초미결구무명현변화,TUNEL법검사미견명현세포조망;ANP조대서광경하가견회장주상상피세포배사、융모탈락,회장초미결구이상최명현,상피세포미융모배렬문란차단왜,TUNEL법제시회장상피조망세포교다,이융모정단위주;MT조대서병리개변、초미결구이상균교ANP조감경,상피조망세포교ANP조감소.ANP조대서각시점혈청IFABP수평교SO조현저승고,차이유통계학의의(P균＜0.05);이MT조대서각시점혈청IFABP수평교ANP조현저하강,차이역유통계학의의(P균＜0.05).결론 ANP가도치IBF장애,장상피세포유불동정도적배사화조망.제시ANP발병조기장도상피세포조망화증생지간실거평형시IBF장애적병리궤제지일.여이MT간예,가이개선ANP발병후적장도병리개변화장도초미결구이상,기작용도경가능시통과항양화작용급억제염증반응,유대진일보적연구증실.
Objective To evaluate the effect of Melatonin (MT) on the ultrastructure and apoptosis of intestinal epithelial cells in rats with acute necrotizing pancreatitis (ANP).Methods Seventy-two rats were randomly divided into groups sham operation (SO group,n=24),ANP (n=24) and ANP+MT (n=24).ANP models were established by injection of 5% sodium taurocholate into the biliopancreatic duct,and laparotomized animals without induction of ANP (sham operation) served as controls.The rats in MT group received melatonin intraperitoneally (50mg/kg body weight) 30 min before operation.The segment of ileum was removed and the detached epithelial cells of ileum were harvested at hours 4,12,24,and 48 after operation.Apoptosis of intestinal epithelium was studied by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method.Segments of ileum were stained and examined under light microscopy and transmission electron microscopy.Serum IFABP were determined using the commercial kits.Results In SO group,no obvious pathological changes were noted in pancreas and ileum mucosa,and no changes in small intestine tissues,TUNEL revealed no remarkable apoptosis.In ANP group,ileal colummar epithelial cell necrosis,hair loss were seen under light microscope,ileum ultrastructural abnormalities being the most obvious and epithelial cell microvilli being in disorder and short;TUNEL showed a lot of ileal epithelial cell apoptoses which were mainly villus top.In MT group,pathological changes and ultrastructural abnormalities were fewer than in ANP group,and epithelial apoptosis cells reduced.Serum IFABP levels at different time points were higher in ANP group than in SO group,the difference was significant (P＜0.05),and lower in MT group than in ANP group,the difference was significant (P＜0.05).Conclusion ANP can lead to IBF barrier,with varying degrees of necrosis and apoptosis in intestinal epithelial,suggesting that the unbalance between intestinal epithelial cell apoptosis and proliferation in early ANP is one of the mechanisms of IBF barrier.MT intervention can improve the intestinal pathological changes and intestinal ultrastructural abnormalities after ANP,which may act through anti-oxidation and inflammatory response inhibition,which needs a further study.