Effect Of Naoling Decoction On The Expression Of α4-NachR And α7-NachR In Hippocampal CA3 Region Of The Model Rats Of Alzheimer Disease

OBJECTIVE:To observe the effect of Naoling Decoction on ethology, hippocamal histomorphology,and expression of a4NachR and a7NachR in CA3 region of the rats with the model Alzheimer disease, and explore the therapeutical effect on Alzheimer disease rats and the potential mechanism of action of Naoling Decoction.METHODS:After Y-electric-maze testing,chooseing thirty SD (spragu-dawleg) rats were classified into five groups:normal group, sham-operated group, model group,western medical group(donepezil group) and traditional Chinese drug group(Naoling Decoctio group). The Alzheimer disease model was established by Aβ1-42 injected into hippocamal in rats. The faculty of learning and memory was evaluated by Y-electric-maze test and Morris water maze experiment.The brain tissues were removed to be made frozen sections and stained with congored to detect the aggradation of Aβ,the changes of cell morphology were detected by HE stain. Expression of a4-NachR and a7-NachR in CA3 region was measured with immunohistochemical staining.RESULTS:1.The results of Y-electric-maze test showed that compared with sham-operated group and normal group, model group's times to evade stimulate is more (P<0.05);compared with model group, Naoling Decoctio group and Piracetam group's times to evade stimulate is less(p<0.05). Meanwhile, there existed no obvious difference between these two therapy groups(p>0.05).2. The results of Morris water maze experiment showed that Compared with sham-operated group and normal group, the escaped and latent period of model group was delayed significantly (P<0.05). In exploratory experiment, the average pass through times in sham operation group and normal group were more than that of other three ones, and that of the model group was lest, there were significant difference (P<0.05). 3.Congored coloration result:Under the light microscope,in the hippocampal fields of rats in sham-operated group and normal group,orange amylaceous aggradation can't be seen, the cells in DG arrange in order. In the hippocampal fields of rats in the model group, significant orange amylaceous aggradation can be seen in the area that injecting Aβ1-42,this denota there is aggradation of Aβin the hippocampal fields of rats in the model group,meanwhile,the cells in DG obviously damaged,neuron loss noticeable,and there is neuroglial cell proliferation.4.Under the light microscope, hippocampal CA3 fields of rats in the sham-operated group and normal group exhibited closely and neatly spaced pyramidal cells, and insignificant neuron loss;in the hippocampal CA3 fields of rats in the model group sparse and disturbed pyramidal cells,noticeable neuron loss and neuroglial cell proliferation could be seen,meanwhile,the number of pyramidal cells is less than sham-operated group and normal group(p<0.05). Neuron loss reduced significantly in the hippocampal CA3 pyramidal cell fields of the two therapy group and cell morphology presented relative normal.5.The result ofα4NachR with immunohistochemical staining denote the model one'masculine cells abouta4NachR was the least in hippocampal CA3 region,and their colour are darker than theirs.6.The result of a7NachR with immunohistochemical staining denote:the normal group,masculine cells abouta7NachR was the most in hippocampal CA3 region, their colour are darkerst.The Naoling Decoctio group and donepezil group had masculine cells between the model one and the normal group。CONCLUSIONS:1.The presentation of results of the study that the model was established by Aβ1-42 injected into hippocamal was blest, because the model rats had the changes of praxiology and pathology.2.The learning and memory of the model rats were decreased obviously, Naoling Decoction can improve the learning and memory of the model rats.3.Naoling Decoction can increase the expression ofa4NachR anda7NachR in hippocampal CA3 of AD rats.