β-淀粉样蛋白介导的阿尔茨海默病模型中BDNF及TRPC3表达及作用研究

Expression and role of BDNF and TRPC3 in β-amyloid-mediated Alzheimer’s disease model

目的 探究在β-淀粉样蛋白诱导的阿尔茨海默病(AD)大鼠模型中,脑源性神经营养因子(brain derived neurotrophic factor,BDNF)及瞬时受体电位通道(transient receptor potential channel,TRPC3)的表达水平和关系。方法选取40只SD大鼠作为研究对象,随机分为假手术组、生理盐水组、AD组以及实验组,其中假手术组剥开颅骨膜后未注射液体,生理盐水组在侧脑室注射生理盐水,AD组应用β-淀粉样蛋白在侧脑室注射,实验组则选取β-淀粉样蛋白联合BNDF注射,模型构建成功后,水迷宫实验检测大鼠空间记忆和学习能力,PCR检测BDNF及TRPC3 mRNA含量,Western blot法测定BDNF及TRPC3蛋白的表达,并分析其作用关系。结果四组大鼠在运动速度方面比较,差异无统计学意义(P>0.05)。而AD组第5天的逃避潜伏期明显高于假手术组、生理盐水组及实验组,差异均有统计学意义(P<0.05)。假手术组、生理盐水组及实验组穿越平台次数均高于AD组,差异有统计学意义(P<0.05)。AD组BDNF和TRPC3 mRNA相对表达水平明显低于假手术组、生理盐水组及实验组,差异有统计学意义(P<0.05),实验组的BDNF mRNA相对表达水平与假手术组、生理盐水组相比,差异无统计学意义(P>0.05)。在BDNF蛋白和TRPC3蛋白表达方面,AD组低于假手术组、生理盐水组及实验组,差异有统计学意义(P<0.05),实验组与假手术组、生理盐水组对比,差异无统计学意义(P>0.05)。结论AD大鼠模型中,BDNF及TRPC3可能与学习记忆能力障碍相关。

Objective To investigate the BDNF and TRPC3 expression levels and relationships in a rat model of Alzheimer’s disease(AD) induced by β-amyloid.Methods 40 SD rats were randomly divided into sham operation group,saline group,AD group and experimental group.The sham operation group was not injected with liquid after excision of the periosteum,and the physiological saline group was injected with saline into the lateral ventricle.AD group was injected with β-amyloid in lateral ventricle,and experimental group was treated with β-amyloid combined with BNDF.After successful model construction,water maze test was used to detect spatial memory and learning ability of rats.PCR detection of BDNF and TRPC3 The mRNA content,Western blot was used to determine the expression of BDNF and TRPC3 protein,and the relationship was analyzed.Results There was no significant difference in the speed of movement between the four groups of rats(P>0.05).The escape latency of the 5 th day in the AD group was significantly higher than the sham operation group,the saline group and the experimental group,and the difference was statistically significant(P<0.05).The number of crossing platforms in the sham operation group,the saline group and the experimental group were higher than those in the AD group,and the difference was statistically significant(P<0.05).The expression levels of BDNF and TRPC3 mRNA in AD group were significantly lower than those in sham operation group,saline group and experimental group,the difference was statistically significant(P<0.05).The expression level of BDNF mRNA in experimental group was compared with sham operation group and the saline group.There was no significant difference(P>0.05).In terms of BDNF protein and TRPC3 protein expression,the AD group was lower than the sham operation group,the saline group and the experimental group,the difference was statistically significant(P<0.05).The experimental group was compared with the sham operation group and the saline group.The difference was not statistically significant(P>0.05).Conclusion BDNF and TRPC3 may be associated with learning and memory dysfunction in a rat model of Alzheimer’s disease.