[Expressions of synaptophysin and BDNF/Trk-B in cerebellum of APPswe/PS1dE9 transgenic mice].

Objective: To observe the expressions of synaptophysin and BDNF/Trk-B in cerebellum of APPswe/PS1dE9 transgenic mice.

Methods: The healthy 9-month old APP/PS1 male mice (n1) and the same wild type male mice(n2) were divided into two groups, APP/PS1 group and wild-type(WT) group. The expressions of synaptophysin and brain-derived neurotrophic factor/tyrosine kinase B (BDNF/Trk-B) in cerebellum were determined by Western blot (n1=6; n2=6) and immunohistochemical(n1=4; n2=4).The possible synaptic changes in APP/PS1 group were observed by using electron microscopy.

Results: Compared with WT group, the expressions of synaptophsin and BDNF/Trk-B in cerebellum were decreased in APP/PS1 group. Increased width of the synaptic cleft and decreased thickness of postsynaptic density were also observed.

Conclusions: In APP/PS1 group, expressions of synaptophsin and BDNF/Trk-B in cerebellum were decreased; changes in ultrastructure of synapses seemed to be widespread alterations. These findings suggest a possible association between expression of BDNF/TrkB and synaptic plasticity in AD cerebellum.