Abstract: ObjectiveTo observe the changes of monoamine oxidase-B (MAO-B), interleukin-6(IL-6) in the cortex and hippocampus of Alzheimer's disease model mice and the effect of traditional Chinese medicine Naofucong.MethodsAlzheimer's disease model was induced in mice by β-amyloid(Aβ)_25-35 icv. Space learning and memorial ability was tested in Morris water maze. The activity of MAO-B was measured by colorimetric method. IL-6 was observed with the immnuohistochemical stain.ResultsMice in the model group presented longer latent periods of Morris water maze(81.3±13.4)s, higher activities of MAO-B in brain cortex and hippocampus (120.12±10.15,83.60±5.29) compare with that of the control group, which was (34.2±10.9)s,(93.09±10.54) and (50.39±9.16)(P<0.05～0.01).There were many IL-6 positive cell in dentate gyrus of hippocampus of the model group. After administration with Naofucong grain, latent periods (43.7±12.7) s and activities of MAO-B (47.11 ± 6.57)in hippocampus were recovered(P<0.05～0.01), and the IL-6 positive cell in dentate gyrus decreased.ConclusionNaofucong grain can antagonize the Aβ_25-35 toxicity by decreasing the overactivition of MAO-B and the excretion of inflammatory medium by microglia, as well as improve the memory function.

Key words: β-amyloid peptide, dementia, monoamine oxidase-B (MAO-B), interleukin-6(IL-6), Naofucong, mice