黄精皂苷对慢性应激抑郁大鼠海马5-HT1AR/cAMP/PKA信号通路的影响

目的探讨黄精皂苷(SRP)对慢性应激抑郁模型大鼠行为学的影响及部分机制。方法 SD大鼠60只随机分为6组:正常组、模型组、SRP(100、200、400 mg/kg)组和氟西汀(2 mg/kg)组。采用不同应激方法建立大鼠慢性应激抑郁模型,观察大鼠行为学指标变化,放射免疫法测定海马环腺苷酸(cAMP)含量,免疫组化法测定海马5-羟色胺受体(5-HT1AR)、蛋白激酶A(PKA)、反应元件结合蛋白(CREB)蛋白表达水平。结果应激刺激后,与正常组相比,模型组大鼠自主活动次数减少,体重降低,糖水消耗减少,处于抑郁状态。免疫组化结果显示,与正常组比较,模型组海马5-HT1AR、cAMP、PKA、CREB表达显著降低,SRP组5-HT1AR、cAMP、PKA、CREB表达显著上调(P<0.01)。结论 SRP对慢性应激抑郁大鼠的行为学有改善作用,可能是通过调节5-HT1AR/cAMP/PKA/CREB信号通路发挥抗抑郁作用。

Effect of saponins of Rhizoma Polygonati on the pathway of 5-HT1AR / cAMP / PKA / CREB in rats with chronic stress induced depression

Objective To explore the behaviors effect and part mechanism of saponins of Rhizoma Polygonati(SRP) in rats with chronic stress.Methods Sixty SD rats were randomly divided into six groups: normal control group,depression model group,SRP(100,200,400 mg / kg) groups,fluoxetine(2 mg / kg) group.Rats were exposed to alternate stressors for 21 days to induce depression.Behavioral indexes were observed during the experiments.cAMP content of hippocampus tissue were detected by radioimmunoassay.The expression of 5-HT1A receptor,PKA,CREB in the hippocampus was determined by immunohistochemistry.Results After chronic stress stimulation,compared with normal control,the behavioral indexes showed that autonomic activities time reduced,the weight lowered,consumption of sugar water reduced in rats of depression model group,so in an obvious depressive state.The expressions of 5-HT1AR,cAMP,PKA,CREB were lower in model group than those in normal group,the SRP group could raise the expression of 5-HT1AR,cAMP,PKA,CREB.Conclusion SRP can improve the behaviors of rats with chronic stress,which may be through the pathway of 5-HT1AR / cAMP / PKA / CREB to play anti-depression effect.