高糖对体外培养的Cajal间质细胞nNOS?HO-2表达的影响

目的:观察高糖对体外培养的Cajal间质细胞(interstitial cells of Cajal,ICC)的nNOS、HO-2表达的影响,探讨NO、CO在糖尿病胃肠功能紊乱的细胞机制.方法:以小鼠小肠为ICC的组织来源,应用酶解法分离、培养ICC.实验分组:正常对照组(葡萄糖浓度为5.5 mmol/L);甘露醇渗透压对照组(葡萄糖浓度为5.5 mmol/L、甘露醇浓度为27.5 mmol/L);高糖组(葡萄糖浓度为33 mmoI/L).通过倒置显微镜观察细胞形态、MTT比色法检测细胞活力、用Western-Blot方法对细胞内的nNOS、HO-2的表达进行分析.结果:与正常组比较,加入葡萄糖后的ICC细胞变圆,突起变短,与周围的邻近细胞网络不明显、细胞活力也下降,而加入甘露醇后的ICC基本没有变化.免疫印迹法检测到甘露醇组的nNOS、HO-2的表达与正常组无明显差异,而高糖组的nNOS、HO-2与正常组比较其表达明显下降.结论:高糖改变了体外培养的ICC的细胞形态、降低了ICC的细胞活力及其细胞内nNOS、HO-2的表达,提示胃肠道组织中的ICC的形态、活力及其胞内的NO、CO可能涉及糖尿病胃肠功能紊乱的发病机制.

Effects of hyperglycemia on the expression of nNOS?HO-2 of interstitial cells of cajal in vitro

Objective:To investigate the relationship between the expression of nNOS?HO-2 and the high contration glucose treatment in the interstitial cells of cajal(ICC) in vitro. Methods:The ICC was isolated from the proxinal colon in newborn rats,and divided into control group,high glucose group and mannitol(osmolarity control) group. Cells viability was assessed by the MTT assay,and the morphologic changes of ICC was observed under microscopy. The expression of nNos and HO-2 was evaluated by Western-blotting. Results:Compared to the controls,high glucose markedly decrease the cell viability. After treatment of high glucose,most of the ICC lost their network of each other,and the expression of nNOS and HO-2 was also decreased. In mannitol treatment ICC,there was no changes in cell viability,cell morphology and nNos and HO-2 compared to the control cells. Conclusion:High glucose treatment could induce ICC cell damage and inhibit the expression of nNos and HO-2. The abnormal expression of nNos and HO-2 may play an important role in the intestines dysfunction of diabetic mellitus.