高血糖对体外培养的胎鼠胰岛Pdx-1基因的影响  

Effects of hyperglycemia on the Pdx-1 gene in fetal rat islets in vitro

作　　者：贾延劼[1] 周燕[2] 董为伟[1] 杨于嘉[3] 

机构地区：[1]重庆医科大学临床学院神经病学研究所,重庆400016 [2]重庆医科大学临床学院放射科,重庆400016 [3]中南大学湘雅医院儿科,长沙410008

出　　处：《重庆医科大学学报》2003年第5期559-561,共3页Journal of Chongqing Medical University

基　　金：国家自然科学基金资助项目 ( 3 0 2 0 0 12 8)

摘　　要：目的 :研究在体外培养时 ,高血糖对胎鼠胰岛胰和十二指肠同源盒基因 - 1(Pdx - 1)和胰岛素基因的影响。方法 :胶原酶法分离胎鼠胰岛 ,分别在葡萄糖浓度为 5 .5mmol/L ,11.1mmol/L ,33.3mmol/L的条件下培养 2 4h。采用胰岛素含量测定、胰岛素释放实验评价胰岛功能 ;免疫细胞化学染色检测Pdx - 1在细胞内的表达 ;逆转录PCR(RT -PCR)检测Pdx - 1和胰岛素mRNA表达水平。结果 :高血糖组 1(11.1mmol/L)胎鼠单位重量胰岛细胞内胰岛素水平和刺激指数高于低糖组 (5 .5mmol/L)和高血糖组 2 (33.3mmol/L)。而且 ,高血糖组胎鼠胰岛Pdx - 1蛋白的核移位率和mRNA表达水平均高于低糖组 ,但是高糖组 2胰岛素mRNA表达低于高血糖组 1,与低糖组无显著性差异。结论 :高血糖刺激可以促进胎鼠Pdx - 1表达和转录活性 ,可能是影响胰岛功能和 β细胞对葡萄糖刺激敏感性增加的原因之一。Objective:To investigate the effects of hyperglycemia on the pancreas and duodenal homeobox gene-1 (Pdx-1) and insulin gene in fetal rat islets in vitro.Methods:Fetal rat islets were digested by collagenase and underwent culture at 5.5 mmol/L, 11.1 mmol/L and 33.3 mmol/L glucose concentration respectively.The insulin content of fetal rat islets and insulin releasing test were measured by radioimmunoassay.The expression of Pdx-1 protein and mRNA were evaluated by indirect immunofluorescence cytochemistry staining and reverse transcriptase-polymerase chain reaction (RT-PCR).Results:The results showed that the insulin content and stimulated index of hyperglycemia group 1 ( 11.1 mmol/L) were significantly higher than that of controls ( 5.5 mmol/L) and hyperglycemia group 2 ( 33.3 mmol/L).The majority of Pdx-1 positive cells in control group were confined to the nuclear periphery, but the majority of Pdx-1 positive cells in hyperglycemia groups were translocated to the nucleoplasm, and the expression of Pdx-1 mRNA was also elevated in hyperglycemia groups.However,the expression of insulin mRNA decresed in hyperglycemia group 2.Conclusion:Hyperglycemia may regulate Pdx-1 in fetal rat islets by increasing its protein level and translocation to the nucleus.

关 键 词：高血糖症 PDX-1 胰岛 胰岛素 

分 类 号：R587.1[医药卫生—内分泌]