Effect of transcutaneous auricular vagus nerve stimulation on fasting blood glucose and serum insulin concentration in Zucker diabetes fatty rats

Objective To observe the influence of transcutaneous auricular vagus nerve stimulation (taVNS) on fasting plasma glucose (FPG) and serum insulin (INS) in Zucker diabetes fatty (ZDF) rats and explore the regulatory effect of taVNS on blood glucose in ZDF rats. Methods A total of 20 male ZDF rats were randomized into a model group and a taVNS group, 10 rats in each one. Besides, the other 10 Zucker Lean (ZL) rats were selected to be a control group. The rats in the control group were fed with common forage and those in the model group and the taVNS group were fed with high-sugar and high-fat forage. The intervention of electric stimulation was applied in the rats of taVNS group, with 2/15 Hz in frequency, disperse-dense wave and 2 mA in intensity. Each intervention lasted 30 min, once a day, consecutively for 12 weeks. No any intervention was given in the control group and the model group. The body mass and FPG level were recorded once every 2 weeks in the rats. After the experiment, the rats were sacrificed and blood sample was collected. Enzyme linked immunosorbent assay (ELISA) was adopted to determine the level of serum INS in the rats. Results After the modeling, compared with the control group, the body mass and FPG level were all higher (P Conclusion taVNS apparently improves in hyperglycemia in ZDF rats and increases serum insulin concentration in the rats.