反复饥饿对大鼠空间学习及海马神经元骨架蛋白磷酸化的影响

为了进一步研究饥饿处理对大鼠空间学习、记忆的影响,通过饥饿2 d、恢复喂食3 d的方法,连续60 d,用Morris水迷宫检测大鼠的空间学习能力.免疫印迹检测神经元骨架蛋白—tau蛋白和神经细丝(Neurofilament,NF)磷酸化水平与分布变化,以及骨架蛋白磷酸化调节的关键酯酶磷酸酯酶PP-2A催化亚单位蛋白水平与分布.反复饥饿的大鼠空间学习能力明显差于对照组(P0.05),tau蛋白在Ser199/202位点和Ser396/404位点发生了过度磷酸化(P0.05),NF磷酸化水平无明显改变,PP-2A的催化亚单位蛋白水平下调(P0.05).反复饥饿可以引起大鼠出现空间学习记忆障碍,下调PP-2A催化亚单位蛋白水平,PP-2A活性抑制及tau蛋白发生过度磷酸化.

Repeated Starvation on Cytoskeleton Protein Phosphorylation and Spatial Learning and Memory in Rat Brain

Food was removed for 2 days, then the rats were refeeded for 3 days. Sixty days later, rats were detected the ability of spatial learning and memory by Morris water maze. Phosphorylation levels and distributions of tau protein and neurofilament (NF), level and distribution of protein phosphatase 2A catalytic subunit were detected with specific antibodies by Western blotting. Model rats showed significantly longer latency to find the hidden platform in Morris water maze than the control rats（P<0.05）. The phosphorylation levels of tau was elevated, and the level of PP-2A cytalytic subunit was significantly decreased（P<0.05）. Starvation leads to impairment of spatial learning and memory in rats, hyperphosphorylation of tau protein, and the down-regulation of PP-2A may be at least one of the underlying mechanisms.