Abstract: Objective To investigate how the pro-inflammatory medium of peptidoglycan(PGN) acts on PC12 after endocytosis of amyloid protein β(Aβ)oligomers in activated BV2 cells. Methods PC12 cells and BV2 cells, instead of neurons and microglia separately, were co-cultivated in transfer screen by cell passage method. Aβ_1-42 oligomers were prepared according to Klein WL(2002). The inhibition of PC12 cells was determined by MTT, and the expression of its tau[ps396] protein was determined by Western blot, and the apoptosis of PC12 cells was determined by flow cytometry. Results Aβ oligomers, BV2 cells acted upon by Aβ oligomers, and BV2 cells affected by PGN all could restrain the proliferation of PC12 cells, increase the expression of its tau[ps396], and increase its apoptosis, while the effect of PGN after endocytosis of Aβ oligomers in activated BV2 cells were more remarkable. Conclusion Aβ oligomers can increase the inhibition of PC12 cells, abnormal phosphorylation of tau protein, and the apoptosis, and after endocytosis in activated BV2 cells by PGN, the effect of Aβ oligomers is more remarkable.

Key words: peptidoglycan, microglia, amyloid protein β_1~42 oligomers, PC12 cells, cell co-culture