【摘要】 目的　从胆石症病人胆汁中分离、提纯氨肽酶N(aminopeptidasen ,APN) ,观察其成核活性 ,并探讨熊去氧胆酸对APN的影响。方法　应用ConA亲和层析法、羟基磷灰石柱层析及高压液相离子交换柱法分离提纯胆汁中的APN ,并用模拟胆汁系统观察APN的成核活性及比较胆固醇结石组、熊去氧胆酸 (ursodeoxycholicacid ,UDCA)组及对照组胆汁中各种成分的变化。结果　APN的纯化倍数达 339倍 ,该酶的活性为 42 0mU/ug。提纯的APN经SDS PAGE及SepharoseG 2 0 0鉴定为单一成分 ,其分子量为 130KDa。用体外模拟胆汁观察APN的成核活性为 0 5 742 ,表明APN具有促成核活性 ,发现胆固醇结石患者的APN活性较无结石者升高 ,服用UDCA后APN活性降低。胆固醇饱和指数 (cholesterolsaturationindex ,CSI)在胆固醇结石患者较无结石者升高 ,服用UDCA后CSI降低 ;与APN活性下降相平行。结论　APN可能在胆固醇结石形成中通过促进成核并影响胆汁CSI起一定作用。更多还原

【Abstract】 Objective[WT5”BZ] Aminopeptidase N (APN) was purified from the bile of patients with gallstones and its nucleation effect was studied in order to evaluate the effect of ursodeoxycholic acid (UDCA) on APN.[WT5”HZ] Methods[WT5”BZ] APN was purified from bile of patients with gallstones. Purification procedures included ConA affinity chromatography, hydroxyapatite column chromatography and HPLC. A series of comparison was done in 3 groups: 12 patients with cholesterol gallstones (group Ⅰ), 12 matched patients treated with UDCA (group Ⅱ) as well as 12 patients without gallstones (group Ⅲ).[WT5”HZ] Results[WT5”BZ] APN was finally purified to 339 fold with its specific activity of 420 mU/ug. SDS PAGE and G 200 gel filtration showed the homogeneity of the purified APN and its molecular weight of 130 000. Western blotting showed that the purified APN cross reacted with the mouse anti human monoclonal antibody. Nucleation time (NT) of APN was shorter than the control ( P <0.01).The APN activity of patients in group Ⅰ was higher than that of patients in group Ⅲ , and was decreased by UDCA therapy. [WT5”HZ]Conclusions[WT5”BZ] Our results demonstrated that APN is a natural pronucleating factor in human bile. There is quantitative difference of APN activity between gallbladder bile of patients with and without cholesterol gallstones. UDCA can lower APN activity in gallbladder bile. So APN might play some critical role in the formation of human cholesterol gallstones. [WT5”HZ]更多还原