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目的 观察β-1,4-半乳糖基转移酶-Ⅰ(β-1,4-galactosyltransferase-Ⅰ,β-1,4-GalT-Ⅰ)基因B4GALT1和蛋白在先天性巨结肠(HD)中的表达及其催化合成的β-1,4-半乳糖苷键(β-1,4-galactosylated carbohydrate,Galβ1-4GlcNAc)糖链在HD中的表达和分布,探讨它们与HD的发病关系及其意义.方法 运用RT-PCR和Western blot技术检测37例HD患儿狭窄段(无神经节细胞段)、移行段、正常段结肠肠壁组织和6例对照组肠套患儿中B4GALT1 mRNA和β-1,4-GalT-Ⅰ蛋白的表达,计算其相对量并进行比较分析.采用免疫组织化学方法观察肠壁内各层之间β-1,4-半乳糖苷键(利用特异性识别β-1,4-半乳糖苷键的蓖麻凝集素)的分布情况.结果 RT-PCR和Western blot结果显示B4GALT1基因及β-1,4-GalT-Ⅰ蛋白在狭窄段表达明显增高,从狭窄段到正常段逐渐减低,差异有统计学意义(P<0.05),HD扩张段和对照组肠段表达差异无统计学意义;免疫组化结果显示,特异识别β-1,4-半乳糖苷键糖链结构的蓖麻凝集素(RCA-Ⅰ)染色面积及染色强度从狭窄段到正常段依次减弱,差异有统计学意义(P<0.05),同样HD扩张段和对照组肠段RCA-Ⅰ的表达差异无统计学意义,两者呈正相关.结论 β-1,4-GalT-Ⅰ在HD狭窄段(无神经节细胞段)表达增高是内在的,它与HD的发生可能存在某种内在的联系.“,”Objective To investigate the expression levels of β-1,4-galactosyltransferase-Ⅰ, detect the locations changes of the total galactosylated of glycoproteins (β1-4GlcNAc) in different segments of colonic tissues from patients with HD and analyze their potential pathogenic roles in Hirschsprung’s disease. Methods The B4GALT1 mRNAs andβ-1,4-GalT-Ⅰproteins expression in the aganglionic, transitional and normal segment in 37 cases with HD and 6 control samples from the children with intussusception was assayed by real-time PCR and Western blot, respectively. Immunohistochemistry was used to determine the expression and localization of Ricinus communis agglutinin (RCA-Ⅰ) in the three segments tissues and control bowels. Results The B4GALT1 mRNA and protein levels of β-1,4-galactosyltransferase-Ⅰin aganglionic segment showed a significant increase when they were compared to the normal segment (P<0.05). There were no significant differences in theβ-1,4-galactosyltransferase-Ⅰexpression between the normal ganglionic segment of HD patients and control bowels. Immunohistochemistry indicates the expression of RCA-Ⅰwas staining higher in aganglionic segment than those in normal control tissues. Moderate expression of RCA-Ⅰwere observed in the migratory segment, which was significantly different from that in the ganglionic and aganglionic segments in patients with HD. The RCA-Ⅰexpression in the normal ganglionic segment of HD patients and control bowels had no significant differences. Conclusion The increased expression ofβ-1,4-galactosyltransferase-Ⅰin aganglionic segment may cause early stop of the differentiation and migration of enteric nervous cells, and its expression may be related to the cause of HD.