助阳开郁方对抑郁症大鼠海马BDNF表达及其胞内信号转导通路的影响

Effects of Zhuyang Kaiyu formula on BDNF expression and intracellular signal transduction pathway in rat hippocampus with depression

目的:基于海马内环磷酸腺苷(cAMP)-cAMP反应元件结合蛋白(CREB)-脑源性神经营养因子(BDNF)信号转导通路探讨助阳开郁方治疗抑郁症的作用机制。方法:36只雄性大鼠随机分为正常组、模型组、助阳开郁方高、中、低剂量组和氟西汀组,每组6只。除正常组外,其余各组接受慢性不可预知温和应激刺激并孤养28 d。在造模同时正常组和模型组给予生理盐水灌胃,助阳开郁方高、中、低剂量组分别给予助阳开郁方浓缩煎剂(11.7 g/kg、23.4 g/kg、46.8 g/kg)灌胃,氟西汀组灌胃盐酸氟西汀(3.33 mg/kg),造模及药物干预结束后取大鼠海马组织,酶联免疫吸附试验(ELISA)测定cAMP含量,实时荧光定量聚合酶链式反应(RT-PCR)检测BDNF、CREB mRNA的表达水平。结果:模型组大鼠海马组织cAMP水平和BDNF、CREB mRNA的表达量明显低于正常组大鼠(P<0.05,P<0.01);与模型组比较,助阳开郁方高剂量组、氟西汀组大鼠海马cAMP含量明显增高,同时助阳开郁方高剂量组大鼠海马CREB、BDNF mRNA表达水平显著上调(P<0.01,P<0.05)。结论:抑郁症大鼠海马cAMP-CREB-BDNF通路中信号分子的表达异常,助阳开郁方抗抑郁作用可能与调节海马组织BDNF的表达及其信号转导通路的关键分子的表达与功能有关。

Objective:To explore the mechanism of Zhuyang Kaiyu formula(ZKF)in the treatment of depression based on cyclic adenosine monophosphat(cAMP)-cAMP response-element binding protein(CREB)-bursa-derived neurotropic factor(BDNF)signal transduction pathway in hippocampus. Methods:36 male rats were randomly divided into normal group,model group,low-dose,middle-dose,high-dose ZKF groups and fluoxetine group,with 6 rats in each group. The rats in low-dose,middle-dose and high-dose ZKF groups were given aqueous solution of ZKF 11.7 g/kg,23.4 g/kg,46.8 g/kg respectively,the rats in fluoxetine group were given aqueous solution of 3.33 mg/kg fluoxetine hydrochloride dispersion tablets,while the rats in normal control group and model group were given solution. Except for normal control group,rats in all the other groups were received gavage administration and chronic unpredictable mild stress(CUMS)combined with isolation stimulus simultaneously for 28 days. The rats hippocampal tissues were taken out after drug intervention,the content of cAMP in depression rat hypothalamu tissue was detected by ELLSA,and the mRNA expressions of BDNF and CREB were detected by RT-PCR. Results:The contents of cAMP and the mRNA expressions of BDNF and CREB in the model group were significantly decreased compared to normal group. Compared with model group,the contents of cAMP in high-dose ZKF group and fluoxetine group were increased obviously,and expressions of CREB and BDNF mRNA in middle-dose and high-dose ZKF groups were significantly increased. Conclusion:The expression of signal molecules in hippocampal cAMP-CREB-BDNF transduction pathway was abnormal in depression rats,the antidepressant effects of ZKF may be correlated with its effect on the expression of BDNF and the expression and function of signal molecules in intracellular signal transduction pathway which is regulated in hippocampus.