Identification of genes associated with epithelial growth using Ileojejunal transposition model

(1)差异显示法筛选肠上皮基因：采用SD大鼠回肠空肠移位模型，分离肠上皮细胞。我们亚克隆了8个基因并进行了测序，结果表明这些克隆都编码线粒体基因。差异表达未得到证实，提示线粒体基因的选择可能是由于伴随差异显示的技术问题。b.建立SD大鼠短肠模型，分离肠上皮细胞。我们从80个差异显示中亚克隆了11个基因，包括线粒体基因和溶质载体家族9，异构体3调节因子1。(2)用0，25，50和100 ng/mlGLP2刺激体外培养的IEC6细胞鸟氨酸脱羧酶(ODC)诱导，检测ODC mRNA的表达。刺激后ODC mRNA表达稳定。以表皮生长因子作为阳性对照，诱导ODC基因表达。(3)建立大鼠全结肠切除后肠适应模型，分析残留回肠上皮细胞的基因表达。回肠远端11b-羟基类固醇脱氢酶2(11b-HSD2)的表达显著增加，可能是由于血液中的醛固酮升高所致。(4)本研究的困难是由于回肠空肠移位模型的结果不一致和基因筛选技术、差异显示技术的局限性。

(1)Epithelial gene screening by differential displaya.Ileojeiunal transposition (IJT) modelIleojejunal transposition was performed using SD rats and samall intestinal epithelial cells were isolated. We subcloned 8 gene and sequenced, resulting that all these clones encoded mitochondrial genes. Differential expresssion was not confirmed, indicating that selection of mitochondrial genes may be due to technical issues accompanied with differential display.b.Short bowel modelShor bowel model was established in SD rats and samall intestinal epithelial cells were isolated. We subcloned 11 genes including mitochondrial genes and solute carrier family 9, isoform 3 regulator 1from 80 differential displays.(2)ornithine decarboxylase(ODC) induction in vitroIEC6 cells were stimulated 0, 25, 50, and 100 ng/ml glucagon-like peptide 2 (GLP2) and expression of ODC mRNA was examined. Expression of ODC mRNA was stabe after stimulation. In contast, epidermal growth factor, used as a positive control, induced ODC mRNA.(3)Intestinal adaptation following total colectomyRat total volectomy model was established and gene expression of remnant ileal epithelia was analyzed. 11b-hydroxysteroi dehydrogenase type2 (11b-HSD2) was remarkablly induced in the distal ileum probablly due to enhanced aldosterone in blood.(4)ConclusionDifficulties in this project was due to 1.inconsistent results from ileojejunal transposition model and 2.limitation of gene screening technique, differential display.