益肾化浊方对阿尔茨海默病模型大鼠海马区BDNF及其受体TrkB蛋白表达的影响

Effects of Yishen Huazhuo Decoction on Expression of BDNF and Its Trk B Receptor in Hippocampus of Experimental Rat Model of Alzheimer's Disease

目的:观察益肾化浊方对阿尔茨海默病(AD)模型大鼠海马区脑源性神经营养因子(BDNF)及其酪氨酸蛋白激酶受体B(Trk B)蛋白表达的影响,探讨益肾化浊方治疗AD的作用途径。方法:雄性SD大鼠随机分为5组,即假手术组、AD模型组、益肾化浊方低、中、高剂量组。参照《大鼠脑立体定位图谱》,选取左侧侧脑室注射聚集态的β-淀粉样蛋白25-35(Aβ25-35),制备AD大鼠模型。造模成功后予益肾化浊方低、中、高剂量(2.8,5.6,11.2 g·kg-1),每日灌胃1次,共灌胃4周。采用Morris水迷宫测试各组大鼠学习记忆能力,Western blot法检测海马区BDNF及其受体Trk B蛋白表达的变化。结果:与假手术组比较,模型组大鼠逃避潜伏期时间延长,穿越平台次数减少,海马区BDNF及其受体Trk B蛋白表达显著下降,差异均有统计学意义(P<0.05);与模型组相比,益肾化浊方低、中、高剂量组大鼠逃避潜伏期时间缩短,穿越平台次数增加,海马区BDNF及其受体Trk B蛋白表达明显升高,差异均有统计学意义(P<0.05)。结论:益肾化浊方可能通过促进AD模型大鼠海马区BDNF及其受体Trk B蛋白的表达,进而改善其学习记忆功能。

Objective： To observe the effect of Yishen Huazhuo decoction on express of brain derived neurotrophic factor （BDNF） and tyrosine kinase keceptor B （TrkB） in the hippocampus of experimental rat model with Alzheimer＇s disease and explore the mechanism of Yishen Huazhuo decoction. Method： Male SD rats were randomly divided into 5 groups, sham operation group, model group, low, middle and high dose group of Yishen Huazhuo decoction. According to the brain stereotaxic atlas of rats, animal model of Alzheimer＇s disease was established by injecting Aβ25-35 into the left lateral ventricle. Treatment groups were given three different doses of Yishen Huazhuo decoction （2.8, 5.6, 11.2 g·kg^-1 ） within the next 4 weeks, once daily. The Morris Water Maze was employed to investigate the function of learning and memory in model rats. The effect of protein expression of BDNF and its TrkB receptor in the hippocampus were detected by means of Western blot. Result： Compared with sham operation group, models＇ learning and memory ability and the protein expression of BDNF and its TrkB receptor in the hippocampus were significantly lower （ P 〈 0.05 ）. Yishen Huazhuo decoction could significantly enhance the learning and memory ability and the protein expression of BDNF as well as its TrkB receptor in the hippoeampus of the rats compared with the model group （P 〈 0.05 ）. Conclusion： Yishen Huazhuodecoction could promote the protein expression of BDNF and its TrkB receptor in the hippocampus, and improve the learning and memory ability of the AD rats.