基于micro-CT的2型糖尿病大鼠骨骼特点的研究

目的 运用micro-CT及组织形态学方法研究糖尿病大鼠骨骼的特点。方法 实验对象选择8周龄雄性SD大鼠20只，分为两组:正常组10只，实验组10只。实验组通过饲喂高脂饲料同时辅以注射小剂量链脲佐菌素（STZ）（30 mg/kg）的方法建立2型糖尿病大鼠模型。通过血糖、血清胰岛素、胰腺组织切片染色评价建模效果，通过股骨micro-CT扫描及组织学方法比较实验组和正常组大鼠骨骼的特点。结果 正常组（n =10)体质量及血糖低于实验组（n =9)（P <0.05），两组胰岛素水平基本相当（P >0.05）。胰腺组织切片染色结果显示:正常组胰岛形态规则，边缘界清，胰岛细胞排列紧密。糖尿病组大鼠胰岛形态不规则，边缘模糊不清，胰岛细胞稀疏，纤维结缔组织增多。Micro-CT扫描结果显示:实验组和正常组相比，其股骨的骨体积（单位:%，正常组:0.194 2±2.332，实验组:0.080 7±1.952）、骨小梁厚度（单位:mm，正常组:0.052 9±0.004 5，实验组:0.043 6±0.002 4）以及骨小梁数量（单位:mm-1，正常组:3.668 8±0.134 5，实验组:1.851 7±0.288 8）均减少（P <0.05）。骨小梁间隙（单位:mm，正常组:0.219 6±0.072 1，实验组:0.496 5±0.076 4）增加（P <0.05）。股骨组织形态计量学检测结果与micro-CT结果一致。结论 本实验建立的大鼠模型可以在一定程度上模拟临床2型糖尿病的骨骼特点，micro-CT下表现为骨体积、骨小梁密度以及骨小梁数量下降。

Study on the Characteristics of Bone in Type-2 Diabetic Rats by Micro-CT

Objective To study the characteristics of bone in type 2 diabetic rats using micro-CT. Methods Sixteen male Sprague Dawley(SD) rats, aged 8 week-old, were randomly divided into normal group and experimental group (n =10). Afer being fed with high-fat chow, the rats in experimental group were given low-dose streptozotocin (STZ,30 mg/kg) to induce type 2 diabetic disease. Serum glucose, insulin and tissue sections of pancreas is used to evaluate the effect of type 2 diabetic rat model. The characteristics of bone in the two groups were measured and compared by micro-CT. Results Compared with normal group (n =10), the experimental group (n =9) had the body mass and serum glucose increased significantly (P <0.05). The level of serum insulin was equivalent in two groups(P >0.05). Pancreatic tissue section staining showed in experimental group islet morphology was irregular, edge boundary was blur and islet cells were saperated with increasing fiber tissue. The bone volume of normal and experimental groups were (0.194 2±2.332)%, and (0.080 7±1.952)%, respectively. Trabecular thickness (unit:mm) were 0.052 9±0.004 5 and 0.043 6±0.002 4, respectively. Trabecular number (unit:mm^-1) were 3.668 8±0.134 5, and 1.851 7±0.288 8, respectively (P <0.05), while trabecular space (unit:mm) were 0.219 6±0.072 1 and 0.496 5±0.076 4, respectively(P <0.05). Bone tissue morphology metrology test results was consistent with the results of micro-CT. Conclusion The diabetic rat model showed CM(155.3mm]declined bone volume and trabecular density, trabecular number. Micro-CT may be more intuitive in bone quality inspection to reflect the characteristics of bone microstructure morphology.