Effect Of Reinforcing Spleen And Kidney Herbal Paste On Learning And Memory Function In Elderly Spontaneously Hypertensive Rats

Objective:To explore the effect of reinforcing spleen and kidney herbal paste on learning and memory function in elderly spontaneous hypertensive rats(SHR)and its possible mechanism.Methods:Male 12-month-old spontaneously hypertensive rats(SHR)received low,medium and high dosages of reinforcing spleen and kidney herbal paste for 4 weeks.Morris water maze(MWM)experiments was performed to test the learning and memory function of the rats.Number of neurons in hippocampus was counted by Nissl staining.Western blot was applied to detect the expression of learning and memory function related proteins contaning N-methyl-d-aspartate receptor 2B(NMDAR 2B),glutamate receptor 1(GluA1),phosphorylated-calmodulin-dependent protein kinase ?(p-CaMK ?),phosphorylated-cAMP responsive element-binding protein(p-CREB)and phosphorylated-Tyrosine Kinase receptor B(p-TrkB)in rat hippocampus.Results:The results of the MWM experiments showed that when compared with the young SHR,the latency time of elderly SHR increased significantly,the times of entering the platform quadrant decreased,percentage of time at the target platform quadrant and percentage of path length in quadrant decreased,exhibiting significant learning and memory dysfunction.High dose treatment with reinforcing spleen and kidney herbal paste decreased the latency time at first day,then increased the number of times entering the target platform quadrant,percentage of time of staying at the target platform quadrant,and percentage of path length in elderly SHR compared with your SHR.Nissl staining showed that the number of neurons in the hippocampal dentate gyrus(DG)region of the elderly SHR was decreased,which was increased by medium and high dose treatment with reinforcing spleen and kidney herbal paste.Western blot results showed that learning and memory function-related protein expressions(NMDAR 2B,GluA1,phosphorylated-CaMK ?,and phosphorylated-CREB)was significantly reduced in the hippocampus of elderly SHR but was increased in the high dose treatment group.Conclusions:(1)The elderly SHR have severe cognitive dysfunction.(2)reinforcing spleen and kidney herbal paste can effectively inhibit neuron loss in hippocampal DG area.(3)reinforcing spleen and kidney herbal paste can improve the learning and memory function of the elderly SHR by regulating the expression of memory function related proteins in the molecular mechanism of LTP.