Aβ40 induces expression of p53 with apoptosis of hippocampal cells in rat brains

Objective To investigate the association between Aβ40 and the expression of p53 protein. Methods In order to study the p53 expression and the apoptotic action induced by Aβ40,we used anti-p53 immunohistochemical staining,TUNEL staining and transmission electron microscopy. Results After Aβ40 injection 3-day and 7-day,we demonstrated that there was p53 immunohistochemical staining in the formalin-fixed hippocampal sections of the rats after injection with Aβ40.None of P53 immunoreactivity was detectable in the brains of control rats. By TUNEL staining,we confirmed that there was TUNEL positive staining in the sections of the experimental group rats. By transmission electron microscopy analysis,cells dying in apoptosis after a 3 and 7-day of survival time,are characterized by pyknotic and packed chromatin into smooth masses,cyclic,or lunar masses(apoptotic bodies) under the nuclear membrane. There were no cells by apoptosis in the control group. Conclusion Results indicate that Aβ40 can induce p53 expression in the SD rat brains.