Identification of genes associated with epithelial growth using Ileojejunal transposition model

（1）应用差异表达法筛选肠上皮细胞基因：采用SD大鼠行回肠空肠转位术，分离小肠上皮细胞。我们对其中8个基因进行了亚克隆和测序，结果表明这些克隆均编码线粒体基因。差异表达未得到证实，表明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.短肠模型建立SD大鼠Shor肠模型，分离小肠上皮细胞。我们从80个差异显示基因中克隆了11个基因，包括线粒体基因和溶质载体家族9、异构体3调节子1。（2）鸟氨酸脱羧酶（ODC）的体外诱导：以胰高血糖素样肽2（GLP 2）为刺激剂，分别以0、25、50和100 ng/ml刺激IEC 6细胞，检测ODC mRNA的表达。刺激后ODC mRNA表达稳定。而表皮生长因子作为阳性对照，则诱导ODC mRNA的表达。（3）全结肠切除术后的肠道适应性建立大鼠全结肠切除模型，分析大鼠回肠残端上皮基因表达。11b-羟类固醇脱氢酶2型（11b-HSD 2）在回肠末端可被诱导，可能与血中醛固酮增加有关。（4）结论本研究的难点在于：1.回空肠转位模型的结果不一致; 2.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.