Bcl-2和Fas对不完全梗阻性黄疸大鼠胆总管上皮细胞凋亡的调节作用

Effect of Bci-2 and Fas protein expression on the apoptosis of common bile duct epithelia in rats with incompletely obstructive jaundice

目的探讨Bcl-2、Fas蛋白在不完全梗阻性黄疽大鼠胆总管的表达及其与胆总管上皮细胞凋亡的关系。方法60只SD大鼠，雌雄不拘，随机分为不完全梗阻性黄疸组40只（A组）和实验对照组20只（B组）。A组不完全结扎大鼠胆总管建立动物模型，B组仅打开腹腔游离胆总管末端即可。二组分别于术后3、7、14、21d处死10只和5只，检测血清胆红素（TBIL）的变化，观察胆总管病理组织学的改变，TUNEL法观察胆总管上皮细胞凋亡，免疫组化法检测大鼠胆总管上皮中Bcl-2、Fas蛋白的表达。结果A组随着梗阻性黄疸时间的延长，血清胆红素逐渐增高，胆总管上皮细胞凋亡数逐渐增多；B组变化不明显。A组与B组比较有显著性差异（P〈0．05）。A组Bcl-2、Fas蛋白在结扎后3d均为弱阳性表达，7、14d均为阳性表达，21d均为强阳性表达；B组均为阴性表达。结论不完全梗阻性黄疸时细胞凋亡增加是机体维持自身稳定的一个重要机制。Fas、Bcl-2蛋白对不完全梗阻性黄疸大鼠胆总管上皮细胞凋亡有调节作用。

Objective To investigate the relationship between the expression of Bcl-2 and Fas protein and the apoptosis of common bile duct epithelia in rats with incompletely obstructive jaundice. Methods A total of 60 adult male or female Sprague-Dawley （SD） rats were randomly divided into two groups： incompletely obstructive jaundice rats by ligaturing common bile ducts （Group A, n = 40） and the sham-operation rats （Group B, n = 20）. The two groups of rats were sacrificed on postop- erative day 3, 7, 14 and 21, respectively. Then serum bilirubin levels were tested and histopathological changes of common bile ducts were observed. Apoptosis of common bile duct tissues was detected by TUNEL method. The immunohistochemical technique was adopted for detecting the Bel-2 and Fas protein expression. Results In group A,with the time prolonging of incompletely obstructive jaundice, the value of serum bilirubin increased and apoptotic cells of common bile duct epithelia increased, compared to those in group B （P〈0. 05）. In group A, Bcl-2 and Fas protein were both weak positive on the 3rd day postoperatively, positive on the 7th and the 14th day, strong positive on the 21st day, while all negative in group B. Conclusions It is an important mechanism that the organism maintains itself stable by increasing the amount of apoptotic common bile duct epithelia when the common bile duct is incompletely obstructive. Bcl-2 and Fas protein may regulate the apoptosis of common bile duct epithelia in rats with incompletely obstructive jaundice.