Objective:To observe the expression of RGMa and RhoA in the hippocampus of cognitive impairment rats induced by Aβ1-40. Methods:Morris water maze was used to study the cognitive function

and reverse transcription-polymerase chain reaction(RT-PCR)method was used to determine the changes of RGMa mRNA and RhoA mRNA expressions. mmunohistochemistry was used to detect the expression of RGMa protein. Results:Model group showed learning and memory impairment

the expression levels of RGMa mRNA and protein in the hippocampus decreased compared with control group(p<0.05)

in contrast

RhoA mRNA upregulated. Conclusion:Morris water maze test showed cognitive impairment in rats.The down regulation of RGMa expression and the increasing of RhoA expression may be involved in hippocampal neuronal degeneration pathological process of cognitive impairment induced by the Aβ in rats.