Protective action of puerrin on learning or memory ability and hippocampal structure in ovariectomized rats

Objective:To study the effects of Puerarin on learning and memory ability and hippocampal structure in ovariectomized rats.Methods:The female rats were randomly assigned into six groups:model group,premarin group,Puerarin groups(120,60,30mg/kg),and control group,continuous treatment 30d,The rats' learning and memory ability was tested in Morris maze,and the hippocampal CA1 synaptic ultrastructure was observed by electron microscope.Results:The rats' escape latencies was shortened with increasing training days in high-dose(120mg/kg) and mid-dose(60mg/kg) Puerarin(P0.01,P0.05),the times across the platform was increased in high-dose(120mg/kg) and mid-dose(60mg/kg) Puerarin groups(P0.05),and the quadrant dwell time in the platform were prolonged also(P0.05);The model group rats' nerve nuclei were destroied,the nucleolus was not clear,the cytoplasm was abnormal in area CA1 of the hippocampus,and the rats nuclear shape is regular,and nuclear membrane is smooth in high dose(120mg/kg) puerarin;the rats nuclei morphology and cytoplasmic lipofuscin is improved obviously in mid-dose(60mg/kg) puerarin group,but the low-doses(30mg/kg) group is worse.Conclusion:The learning and memory deficits or hippocampal CA1 structure destroyed have been protected effectively by Puerarins in ovariectomized rats.