Chronic BCNU administration alters APP metabolites in the mouse brain. Mice were treated as in legends to Figure 5. A) Immunoblots showing APP (long exposure, LE and short exposure, SE), CTFs, sAPPα and actin as loading control. B) Quantification of Aβ by sandwich ELISA revealed robust reduction of Aβ40 by 75% (P < 0.01) in BCNU-treated brains compared to saline-treated mice. C) Quantification of CTFs also revealed significant reductions by 39% (P < 0.05) in BCNU-treated mouse brains. D) sAPPα levels were increased by 45% (P < 0.05) in BCNU-treated mice. In each group, n = 5, ± SEM. *, P < 0.05, **, P < 0.01 in BCNU-treated APdE9 mice versus vehicle-treated APdE9 mice by student's t test. Aβ, amyloid β; APP, Alzheimer's precursor protein; BCNU, 1, 3 bis (2-chloroethyl)-1-nitrosourea; CTFs, c-terminal fragments; SEM, standard error of the mean.