中文摘要：

目的研究糖尿病大鼠胃肠排空延迟和空回肠P物质分布的关系，及这一改变是否影响局部寡肽转运体PEPT1的水平。方法Wistar大鼠24只，分为3组（n=8）。1型糖尿病模型加胰岛素治疗组，左脲链霉素（streptozocin，STZ）单次股静脉注射（60mg／kg）诱导1型糖尿病模型，并每天给予1次长效胰岛素（20U／d，皮下注射）控制血糖。1型糖尿病模型组，左脲链霉素（STZ）单次股静脉注射（60mg／kg）诱导1型糖尿病模型，并给予等量生理盐水。正常对照组大鼠经股静脉注射生理盐水。1个月后检测胃肠排空功能，选取胃肠排空明显延迟的动物，通过免疫组化分析空肠起始段与回肠末端SP分布变化。刮取空肠起始段与回肠末端的黏膜细胞，通过免疫印迹技术检测PEPT1水平。结果糖尿病大鼠胃肠推进率低于60％的，其空肠起始段和回肠末端sP分布明显减少（P〈0．05），其中SP在空肠起始段主要分布于黏膜下层，肌层未发现阳性染色，回肠末端除分布于黏膜下层外，黏膜上皮多见阳性染色。与同月龄正常大鼠及STZ加胰岛素注射非糖尿病组相比，糖尿病大鼠空肠起始段与回肠末端黏膜细胞PEPT1的表达水平显著下降（P〈0．05）。结论糖尿病导致的胃排空延迟和空回肠P物质分布下调关系密切，同时也出现空肠起始端与回肠末端PEPT1的表达减少。上述变化可能和糖尿病胃肠营养不良有关。

英文摘要：

of substrate P Objective （SP） and To study the correlation between delayed gastrointestinal emptying and distribn- observe whether their change affects the expression level of local oligopeptide transporter PEPTI. Methods Twenty-four Wistar rats were randomly divided into type 1 diabetes mellitus （DM） model plus insulin therapy group, type 1 DM model group, and normal control group, 8 in each group. One month after rats in type 1 DM model plus insulin therapy group were injected with streptozocin （STZ, 60 mg/kg） through the femoral vein to induce type 1 DM model which was treated with long-acting insulin （20 U/day）by subcutaneous injection to control their blood glucose level, rats in type 1 DM model group were injected with STZ （60 mg/kg）through the femoral vein to induce type 1 DM model which was treated with an equal amount of physiological saline, and those in normal control group were injected with an equal amount of physiological saline through the femoral vein, their gastrointestinal emptying function was examined. Distribu- tion of SP in rats with their gastrointestinal emptying significantly delayed from the starting segment of jejulum to the distal ileum was analyzed by immunohistochemistry. Expression level of PEPT1 in mueosal cells taken from the starting segment of jejulum and the distal ileum was measured by Western blotting. Results The gastroin- testinal emptying rate was lower than 60% and the distribution of SP was significantly less in the starting seg- ment of jejulum and the distal ileum in DM rats （P 〈 0.05 ）. The SP was mainly distributed in submueosal lay- er of the starting segment of jejulum with no positive staining of its muscular layer and in the distal ileum with positive staining of epithelium mucosae. The expression level of PEPT1 in the starting segment of jejulum and the distal ileum was significantly lower in tvne 1 DM model group than in control group and non-DM model group （P 〈 O. 05）. Conclusion DM-induced delay of gastrointestinal emptying is