摘要目的：研究内源性胱硫醚β合酶（CBS）和硫化氢在溃疡性结肠炎（UC）患者中的表达，探讨其在UC发病机制中的可能作用。方法采用SABC法观察CBS在30例活动期UC（活动期UC组）、30例缓解期UC（缓解期UC组）及30例健康体检者（对照组）直肠黏膜组织中的定位；直肠黏膜组织中CBS吸光度值则通过病理图文分析系统计算。采用逆转录-聚合酶链反应（RT-PCR）检测直肠黏膜组织中 CBS mRNA 的相对表达量，同时检测甘油醛-3-磷酸脱氢酶（GAPDH）的表达作为内参照，用凝胶成像分析系统半定量检测mRNA的表达水平，结果以目的条带与GAPDH吸光度的比值表示。检测血清中硫化氢水平。结果活动期UC组血清硫化氢水平、直肠黏膜组织中CBS吸光度值、直肠黏膜组织中CBS mRNA相对表达量明显高于缓解期UC组和对照组[（90.13±3.12）μmol/L 比（50.34±2.34）和（48.13±2.75）μmol/L、0.433±0.037比0.295±0.064和0.214±0.026、1.532±0.134比1.031±0.107和0.986±0.067]，差异有统计学意义（P<0.01）；但缓解期UC组与对照组比较差异无统计学意义（P>0.05）。结论 CBS及硫化氢在活动期UC患者中的异常表达表明其在UC的发病机制中可能起到重要的作用。

abstractsObjective To study the expression of endogenous cystathionine-β-synthase (CBS) and hydrogen sulfide in patients with ulcerative colitis (UC), and explore their possible role in the pathogenesis of UC. Methods Thirty patients with active period UC (active period UC group), 30 patients with remission period UC (remission period UC group) and 30 healthy controls (control group) were selected, and SABC method was used to observe the localization of CBS in rectal mucosal tissues. The optical density value of CBS was analyzed with image analysis systems. The relative expression of CBS mRNA in the rectal mucosa tissue was detected by reverse transcriptase-polymerase chain reaction (RT-PCR), and the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was detected as an internal reference. The expression level of mRNA was detected by semi quantitative analysis with gel imaging analysis system, and the results were expressed as the ratio of the target bands to the GAPDH absorbance. The serum level of hydrogen sulfide was detected. Results The serum level of hydrogen sulfide, optical density value of CBS and relative expression of CBS mRNA of rectal mucosal tissues in active period UC group were significantly higher than those in remission period UC group and control group: (90.13 ± 3.12) μmol/L vs. (50.34 ± 2.34) and (48.13 ± 2.75) μmol/L, 0.433 ± 0.037 vs. 0.295 ± 0.064 and 0.214 ± 0.026, 1.532 ± 0.134 vs. 1.031 ± 0.107 and 0.986 ± 0.067, and there were&nbsp;statistical differences (P < 0.01); but there were no statistical differences between remission period UC group and control group (P>0.05). Conclusions The abnomal expression of CBS and hydrogen sulfide in aactive period UC may play an important role in the pathogenesis of UC.