Protective effects of estrogen on function of learning-memory and neuron of hippocampus in ovariectomized rats

Objective To study the protective effects of estrogen on function of learning-memory and the neuron of hippocampus in the ovariectomized(OVX) rat model.Methods Estrogen 200 μg/kg was injected into rats twice a weak followed the OVX rat models were estestablished(OVX+E2 group).The function of learning-memory was tested by Morris water maze;the tau hyperphosphorylation was detected by immunohistochemistry staining;the pathological changes of hippocampus was observed by HE staining and Bielschowski staining.Results Compared with OVX group,the function of learning-memory of Morris water maze in OVX+E2 group were significant improved(all P0.05);the forms of neurons and neurofibrils in hippocampus CA1 subregion were regular;and the number of tau hyperphosphorylation positive cells was remarkable decreased(all P0.05).Conclusion Estrogen can improve the function impairment of learning-memory and protect the hippocampus neuron in female OVX rats,and decrease the level of tau hyperphosphorylation.