In addition, we explore the effects of NTN-1 on the microglial M1/M2 polarization in Aβ stimulated rats, we examined the expressions of M1 and M2 phenotypic markers in the hippocampus of NTN-1 treated AD rats, the expressions of M1 phenotypic marker (iNOS) was significantly elevated in the AD group, and the expressions of M2 phenotypic marker (Arg1) was reduced compared with the WT group. The gene discussed is ARG1; the disease is Alzheimer disease.