动物造模,2型糖尿病 z-bio 2022-06-29 457

　　Objective: To observe the effect of low-frequency electroacupuncture on the pain threshold and the expression of P2X3 receptors in the L5 dorsal root ganglia in type 2 diabetic neuralgia model rats.

　　Method: Experiment 1: 50 SD rats were randomly divided into 8 control group and 42 model group. The model group was given a high-fat and high-sugar diet combined with low-dose streptozotocin (STZ, 35 mg/kg) intraperitoneal injection to establish a DNP model in rats. The control group was fed with conventional feed and given the same dose of citric acid buffer. injection. In the modeling group, the successfully modeled rats were further divided into a model group (DNP group) and a low-frequency electroacupuncture treatment group (DNP+EA group). For electroacupuncture treatment, bilateral points "Zusanli" and "Kunlun" were selected, the frequency was 2 Hz, the intensity was 1 mA for 15 min, and the last 2 mA was treated for 15 min, once a day, for a total of 7 treatments. The insulin sensitivity index (ISI) and fasting plasma glucose (FPG) levels of rats fed with high-fat and high-glucose for 0, 5 weeks and 0, 5, and 7 weeks were observed. Changes in paw withdrawal thresholds (PWTs) of the hind paw at 0, 5, and 7 weeks of high-fat and high-glucose feeding and 3, 5, and 7 days of electroacupuncture at 6 time points; immunofluorescence assay was used to determine the expression of L5 DRG P2X3 body expression. Experiment 2: The rats with successful DNP modeling were divided into electroacupuncture group (EA+Vehicle group) and P2X3 agonist group (EA+αβ-meATP group). Electroacupuncture is the same as above. In the EA+αβ-meATP group, αβ-meATP (0.6 μmol/L, 100 μL) was injected under the toes of the rats before each electroacupuncture intervention. Rats in the EA+vehicle group were injected with the same dose of PBS buffer, and other interventions were the same. Detection of mechanical pain threshold.

　　Results: ①Compared with the rats in the control group, the ISI of the rats in the model group was significantly decreased after 5 weeks of high-fat and high-sugar feeding (P<0.01), and the FPG was significantly increased after 7 weeks of feeding with high-fat and high-sugar (P<0.01). This indicates that the type 2 diabetes model was successfully established (the success rate of modeling was 69.04%); ②PWTs: Compared with the control group, the bilateral PWTs of the rats in the model group were significantly decreased (P<0.01), indicating that the type 2 DNP model was successfully established; In comparison, the rats in the low-frequency electroacupuncture group showed a significant increase in bilateral PWTs at each time point after treatment (P<0.01); while compared with the electroacupuncture group, the bilateral PWTs in the P2X3 agonist group were significantly decreased (P<0.01). ). ③ The results of immunofluorescence assay showed that compared with the control group, the expression of L5 DRG P2X3 positive cells in the model group was significantly increased (P<0.01); Significantly decreased (P<0.01).

　　Conclusion: Low-frequency electroacupuncture can effectively improve type 2 DNP by down-regulating L5 DRG P2X3 receptors.