胰岛素抵抗在2型糖尿病时血清维生素 D3和骨密度变化中的意义

目的检测胰岛素抵抗(IR)和2型糖尿病(T2DM)大鼠的胰岛鼠抵抗情况、血清25-(OH)D3和1,25-(OH)2D3水平、腰椎和股骨骨密度(BMD),探讨IR与2型糖尿病时血清维生素D3和骨密度变化中的意义。方法 18月龄wistar大鼠30只,分为正常对照组(N组)、胰岛素抵抗组(I组)、糖尿病组(D组),正常血糖胰岛素钳夹技术(EICT)测定各组大鼠IR,葡萄糖输注速率(GIR)表示IR,放免法测定各组大鼠血25-(OH)D3和1,25-(OH)2D3水平,双能X线骨密度测量仪(DEXA)测定各组大鼠腰椎、股骨BMD。结果 D组和I组GIR相当,均显著低于N组(P0.01),I组1,25-(OH)2D3低于N组(P0.05),高于D组(P0.01),三组间25-(OH)D3无显著差异,I组腰椎、股骨BMD低于N照组,高于D组(P0.05)。结论 IR是2型糖尿病导致血清活性维生素D3降低和骨密度下降的重要病理生理基础。

Effect of insulin resistance on the changes of serum 1,25-(OH)2D3 and bone mineral density in type 2 diabetes mellitus

Objective To detect the insulin resistance (IR), the serum level of 25-(OH)2D3 and 1,25-(OH)2D3, and the bone mineral density (BMD) of the lumbar vertebrae and the femur in rats with type 2 diabetes mellitus (T2DM), and to investigate the effect of IR on the changes of serum 1,25-(OH)2D3and BMD in T2DM.Methods Thirty 18-month Wistar rats were randomly divided into normal control group (N), insulin resistance group (I), and diabetes group (D).IR of rats in each group was detected using EICT, expressed as GIR.The serum levels of 25-( OH) D3 and 1, 25-( OH)2D3 were measured using radioimmunoassay.BMD of the lumbar vertebrae and the femur was detected using dual energy X-ray absorptionmetry (DEXA). Results The level of GIR in D group and I group was almost the same, while both were significantly lower than that in N group (P<0.01).The serum level of 1,25-(OH)2D3in I group was lower than that in N group (P<0.05), while higher than that in D group (P<0.01).The serum level of 25-(OH)D3 showed no significant difference among 3 groups.BMD of the lumbar vertebrae and the femur in I group was lower than that in N group, while higher than that in D group (P<0.05).Conclusion IR is the vital pathophysiological factor for the decrease of serum 1,25-(OH)2D3and BMD in T2DM.