离断大鼠迷走神经肝支对血糖血脂水平的影响及其与mTOR表达水平的关系

目的　探讨离断大鼠迷走神经肝支对血糖、血脂水平的影响及其与mTOR表达水平的关系，为糖脂代谢神经调节机制研究提供实验依据。 方法　建立离断迷走神经肝支大鼠模型作为实验组，另设迷走神经肝支探查的假手术组和不作任何处理的对照组，术后每两周检测大鼠血糖、血脂、胰岛素和皮质醇水平、肝和骨骼肌组织的糖原含量以及mTOR的表达水平。 结果　实验组大鼠与对照组大鼠相比，术后2周胰岛素水平升高、肝糖原含量增多、血糖水平降低（P<0.05）；术后6周，肝、骨骼肌组织mTOR表达增多、肝糖原及骨骼肌糖原含量降低、血糖水平增高、甘油三酯水平增高，高密度脂蛋白水平降低（P<0.05）。假手术组和对照组大鼠各项指标各时间点无明显差异（P>0.05）。 结论　离断大鼠迷走神经肝支可导致糖脂代谢以及糖原含量异常，其机制可能与胰岛素水平变化以及肝、骨骼肌mTOR表达水平升高有关。

Effects of severed hepatic branch of vagus nerve on blood glucose and lipid levels and its relationship with mTOR expression level in rats

Objective　To investigate the effect of cutting vagus nerve hepatic branch on blood glucose and lipid levels and its relationship with mTOR expression level in rats, to provide experimental evidence for the study of neuromodulation mechanism of glycolipid metabolism.　Methods　Rat model of hepatic branch of vagus nerve transection was established by surgical method (n=15), and the sham operation group (n=15) with vagus hepatic branch exploration and the control group without any treatment (n=15) were set up. The levels of blood glucose, blood lipid, insulin and cortisol, glycogen content in liver and skeletal muscle and the expression of mTOR were measured every two weeks after operation. Results Compared with the control group, two weeks after operation, the blood glucose level of the experimental group decreased, the content of liver glycogen increased and the level of insulin increased (P<0.05). Six weeks after operation, the level of blood glucose increased, the content of glycogen in liver and skeletal muscle decreased, the level of triglyceride increased, the level of HDL decreased, and the expression of mTOR in liver and skeletal muscle increased (P<0.05). There was no significant difference between the sham group and the control group at each time point (P>0.05). Conclusions The transetion of rat vagus nerve hepatic branch can lead to abnormal glucose and lipid metabolism and glycogen content, which may be related to the changes in insulin level and increased expression of mTOR in liver and skeletal muscle.