神经肌肉电刺激对糖尿病大鼠GLUT4基因表达的影响

目的研究神经肌肉电刺激（neuromuscular electrical stimulation, NMES）对糖尿病大鼠股四头肌葡萄糖轻运载体4（glucose transporter 4, GLUT4）表达的影响。 方法选取24只2型糖尿病大鼠，数字表法随机分为空白组、运动组、NMES组，每组各8只。运动组给予中等强度跑台训练干预；NMES组对大鼠双下肢股四头肌进行NMES。通过尾静脉采血测空腹血糖水平，采用酶联免疫吸附分析法检测大鼠胰岛素水平并计算胰岛素抵抗指数（insulin resistant index, IRI），采用RT-PCR法测定股四头肌GLUT4基因表达量。多组间的比较采用方差分析，进一步两组间的比较采用LSD-t检验。 结果运动组和NMES组实验干预后血糖水平均显著下降（均P<0.01），空白组干预前后血糖水平无明显变化（均P>0.05）。3组大鼠实验干预前后胰岛素水平均无明显改变（t=1.023、2.283、1.775，均P>0.05）；实验干预后运动组和NMES组IRI较实验干预前明显改善（t=10.216、6.748，均P<0.01）。实验干预前，3组大鼠空腹血糖水平及IRI无明显差异（F=1.138、1.040，均P>0.05）；实验干预后，3组大鼠空腹血糖水平、IRI及GLUT4 mRNA表达水平的差异有统计学意义（F=38.415、9.976、275.123，均P<0.01）。实验干预后，运动组和NMES组血糖水平及IRI均显著低于空白组（均P<0.01），股四头肌GLUT4 mRNA的表达水平均显著高于空白组（均P<0.01）；运动组与NMES组血糖水平及IRI的差异均无统计学意义（均P>0.05），运动组大鼠股四头肌GLUT4 mRNA的表达水平显著高于NMES组（P<0.01）。 结论NMES训练可以降低糖尿病大鼠空腹血糖、改善胰岛素抵抗，其作用机制可能与骨骼肌GLUT4基因mRNA水平上调有关。

The effects of neuromuscular electrical stimulation on the expression of GLUT4 mRNA in diabetic rats

ObjectiveTo study the effect of neuromuscular electrical stimulation (NMES) on the expression of glucose transporter 4 (GLUT4) of the quadriceps muscles in diabetic rats. Methods24 type 2 diabetic rats were randomly divided into control group, exercise group and NMES group. The exercise group trained on medium-strength treadmills. The NMES group received electrical stimulation of the quadriceps muscles of the lower limbs. Fasting blood glucose concentration was measured by tail vein blood, insulin concentration and insulin resistance index (IRI) were measured by ELISA, and GLUT4 gene expression was determined by RT-PCR. Anova was used for comparison among groups, and LSD-t test was used for further comparison among two groups. ResultsThe blood glucose levels in the exercise group and NMES group were significantly decreased after intervention (P<0.01), and there was no significant change in control group (P>0.05). There was no significant change in insulin level before and after intervention in all groups (t=1.023, 2.283, 1.775, P>0.05), but the IRI was significantly decreased (t=10.216, 6.748, P<0.01) after intervention in the exercise group and NMES group. Before intervention, there was no significant difference in blood glucose level and IRI between the three groups (F=1.138, 1.040; P>0.05). After intervention, the statistical significance of blood glucose level, IRI and GLUT4 mRNA expression levels in the three groups were observed (F=38.415, 9.976, 275.123, P<0.01). After intervention, the blood glucose level and IRI in the exercise group and NMES group were significantly lower than those in control group (P<0.01), and the expression of GLUT4 mRNA in the quadriceps muscle was significantly higher than that in control group (P<0.01), but there was no significant difference in blood glucose level and IRI between the exercise group and NMES group (P>0.05), and the expression of GLUT4 mRNA in the quadriceps muscle of the exercise group was significantly higher than that in NMES group (P<0.01). ConclusionNMES training can improve insulin resistant to control blood sugar, related with the increase of the expression of GLUT4 mRNA.