中文摘要：

目的研究胆道闭锁（BA）患儿肝内诱导型一氧化氮合酶（iNOS）及其上下游调控因子表达情况，并探讨其与BA进行性肝损伤发生的关系。方法应用免疫组织化学染色法对2002年10月至2007年3月在本院行Kasai手术的38例BA患儿与16例对照儿童肝组织iNOS表达情况进行研究；应用ELASA法对BA患儿和对照组外周血总一氧化氮（NO）代谢产物浓度进行测定；应用TUNEL法对BA患儿和对照组肝内胆管上皮凋亡指数进行测定；应用免疫印记法对BA患儿和对照组肝组织NF-gB表达进行半定量分析。结果iNOS在BA患儿肝组织异常高表达，强度为0．30±0．08，而在对照组肝组织不表达。BA患儿外周血总NO代谢产物浓度为（90．40±12．46）mol／L，明显高于对照组的（63．67±5．78）btmol／L，且BA组总NO代谢产物浓度与血清ALT水平[（152．76±29．59）U／L]呈强正相关（r=0．97）。BA组肝内胆管上皮凋亡指数（54．00±11．67）％远高于正常对照组（20．72±5．63）％，且与肝组织iNOS表达强度呈强正相关（r=0．99）。NF-xB在BA患儿肝组织中的表达（0．74±0．06）明显高于正常对照组（0．22±0．03），且与iNOS表达强度呈强正相关（r=0．97）。结论iNOS异常高表达在BA患儿进行性肝损伤中发挥重要作用，该作用是由iNOS及其上下游调控因子NF-KB、NO共同作用所实现。

英文摘要：

Objective To study the expression of induced nitric oxide synthase （iNOS） and its up-down stream regulatory factors in the liver of biliary atresia （BA） with progressive hepatic damage. Methods The iNOS expressions in the liver of 38 cases of BA （mean age 94. 5 ± 41.5 d）from Oct 2002 to Mar 2007 and 16 cases （mean age 103.1 ± 49. 1 d） without hepatic or biliary disease selected as normal control were examined by immunohistochemistry staining method respectively. The total serum NO metabolites was evaluated by ELISA method; the apoptosis index of bile duct epithelial cells was analyzed by TUNEL method and the nuclear factor-KB （NF-KB） expression was assessed by western blotting with semi-quantitatively method. Results iNOS expression in hepatic tissues of BA was abnormal with average intensity of 0. 30 ± 0. 08, and no expression in the normal control. The BA group had significantly higher levels of total serum NO metabolites （90. 40 ± 12.46 μmol/L） than the normal control （63.67 ± 5.78 μmol/L）. A positive correlation was detected between the concentration of NO metabolites and the serum ALT level （152. 76 ± 29, 59 U/L） in BA group （r= 0. 97）. The TUNEL-labeled apoptosis index in the epithelial cells of bile duct of BA group （54, 00 ± 11.67 M） was significantly higher than that of the normal control （20. 72 ± 5.63%）, and a positive correlation was demonstrated between the apoptosis index and the intensity of iNOS in BA group （r = 0. 99）. The intensity of NF-KB expression in BA group （0. 74 ± 0. 06） was much higher than that of the normal control （0. 22 ± 0. 03） with a positive correlation （r = 0. 97）. Conclusions The abnormal expression of iNOS might play a key role in the progressive hepatic damage of BA. It is controlled by iNOS and the up-down stream regulatory factors of NF-KB and NO.