EFFECTS OF AMYLOID BETA-PROTEIN ON NEURONS AND MICROGLIA IN HIPPOCAMPUS OF RATS

Objective: To study the effects of Aβ25-35 injected into the hippocampus on neurons and microglia in hippocampus of rats.Methods: Male Wistar rats were randomly divided into normal control group and model group(2d, 5d, 15d, 21d after injecting Aβ). Aβ25-35 was injected into hippocampus on both sides of rats to induce Alzheimer's disease model. Thionine staining was used to observe the morphology of neurons in CA1 region of hippocampus and count the number of neurons, Immunohistochemical stain to detect the expression of CD11b(the activation markers of microglial cells).Results: 2d to 15d after injecting Aβ, the pathological changes of neurons in CA1 region of hippocampus got worse progressively; to 21d after injecting Aβ, the pathological changes of neurons in CA1 region alleviated to some extent. 2d to 15d after injecting Aβ, the number of neurons in CA1 region of hippocampus gradually reduced; to 21d, the number of neurons in CA1 region increased but had no statistical signifi cance compared with 15d(P 0.05). The expression level of CD11b in CA1 region of hippocampus was the highest 7d after injecting Aβ, and then gradually decreased.Conclusions:Injecting Aβ25-35 into hippocampus can cause damages of neurons in hippocampus, and induce microglia specific marker CD11b expression increased.