Abstract: ObjectiveTo observe the injured changes of brain myelin sheath structure and myelin basic protein (MBP) content induced by amyloid β peptide (Aβ) and effect of GETO on these changes.MethodsThe experimental rat model of Alzheimer's disease was established with Aβ_1-42 injection into hippocampus. 4 weeks later, the myelin sheath structure of the CA1 area of the rat hippocampus was taken and observed by electromicroscope, and distribution and content of MBP were examined with immunohistochemical method.ResultsThe electromicroscope showed that the structure of myelin sheath became relaxing, disorder, homogenization and default of hippocampus CA1 in the model rats. In GETO treated group, the structure of myelin sheath was integrity and continuum. Immunohistochemical test showed that the staining and numbers of myelin sheath of model rats was thinner than that of normal rats and GETO treated rats. The numbers, mean area and mean density of positive staining axon in hippocampus CA1 of MBP in the model rats were significantly different from those in the normal group and GETO group (P<0.01).ConclusionAβ_1-42 injection into hippocampus in rats can impair myelin sheath to make MBP release and GETO can ameliorate these changes.

Key words: amyloid β peptide, myelin sheath, myelin basic protein (MBP)