胆汁内、外引流术对梗阻性黄疸大鼠小肠黏膜巨噬细胞和TNF-α表达的影响

摘要

目的 探讨胆汁内、外引流术对梗阻性黄疸大鼠肠黏膜巨噬细胞及肿瘤坏死因子α(TNF-α)表达的影响.方法 将60 只体重300~350 g 的成年健康雄性SD大鼠随机分为四组:梗阻性黄疸组(OJ)、胆汁外引流组(ED)、胆汁内引流组(ID)及假手术对照组(SH).于二次术后第7 天留取末端回肠标本.应用免疫组化染色测定大鼠肠黏膜CD68及TNF-α 表达的变化.结果 四组大鼠模型均成功建立.梗黄时大鼠肠黏膜CD68及TNF-α的表达水平较假手术组明显增强,平均光密度升高[(0.58±0.050)、(0.28±0.034),P<0.01;(0.34±0.042)、(0.14±0.021),P<0.01].黄疸由胆汁内引流术解除后,大鼠肠黏膜CD68的表达与梗阻性黄疸组相比明显减少,平均光密度降低[(0.49±0.049),P<0.05];黄疸由胆汁外引流术解除后,大鼠肠黏膜CD68表达水平减少,平均光密度降低(0.55±0.076),与梗黄组比较差异无统计学意义(P>0.05).经胆汁内外引流术解除黄疸后,大鼠肠黏膜TNF-α表达受到抑制,平均光密度均降低[(0.29±0.034)、(0.33±0.030)],但内引流组较梗黄组差异有显著统计学意义(P<0.01)、外引流组差异则无统计学意义(P>0.05).结论 梗阻性黄疸时肠黏膜免疫屏障受损,巨噬细胞及细胞因子TNF-α 分泌紊乱,胆汁内引流术能显著降低肠黏膜炎症因子的分泌,但胆汁外引流术却不能改善这一状况,提示梗阻性黄疸术前通过胆汁内引流术解除要优于胆汁外引流术.%Objective To explore the effect of internal and external biliary drainages on macrophages and tumor necrosis factor-α (TNF-α) levels of intestinal mucosa in rats with obstructive jaundice. Methods Sixty adult healthy male SD rats with the weight of 300-350 g were randomly divided into four groups: obstructive jaundice group (OJ), external drainage group (ED), internal biliary drainage group (ID) and sham operation group (SH). The ileum tissues were taken on the 7th day after the second surgery. Immunohistochemistry was used to determine the expression change of CD68 and TNF-α. Results Four groups of rats model were successfully established. Compared with SH group, the levels of CD68 and TNF-α in rat intestinal mucosa of O J group were significantly increased, and the mean optical density was increased [(0.58±0.050) vs (0.28±0.037), PO.01; (0.34±0.040) vs (0.14±0.021), PO.01]. Compared with OJ group, the levels of CD68 of the ID group significantly decreased and the mean optical density was significantly decreased [(0.49±0.049), P<0.05)]. Compared with the OJ group, the level of CD68 of the ED group,was slightly decreased and the mean optical density was slightly decreased, with no statistically significant difference [(0.55±0.076), P>0.05]. The level of TNF-α in both ID and ED groups was reduced. The mean optical density was decreased [(0.29± 0.034), (0.33±0.030)]. There was significant difference between ID group and OJ group (PO.01). but there was no significant difference between OJ and ED group (P>0.05). Conclusion After common bile duct ligation, the level of macrophages and tumor necrosis factor-α (TNF-α) in intestinal mucosa are significantly elevated in obstructive jaundice. The level of inflammatory cytokines could be reduced significantly by internal biliary drainage in intestinal mucosa of rats with obstructive jaundice, while external biliary drainage had less effect. Internal biliary drainage could be more efficient than external biliary drainage in the relief of intestinal mucosa injury induced by obstructive jaundice.