FIGURE 8.

Degradation ratios of Aβ(1–40) and Aβ(11–40) by neprilysin. A, changes of Aβ(1–40) and Aβ(11–40) amounts by incubations with neprilysin. Synthetic human Aβ(1–40) and Aβ(11–40) peptides were incubated with (Neprilysin) or without (Buffer) a recombinant human neprilysin for indicated time (h). The reactions were subject to Western blot analysis with anti-pan Aβ antibody 4G8. The number indicates a molecular size marker (in kDa). B, the levels of Aβ(1–40) (closed triangle) and Aβ(11–40) (open circle) in the presence of neprilysin were standardized by the levels of peptides in the absence of neprilysin, and indicated as ratios to the levels shown in 0 h, which was assigned a reference value of 100 (%). Statistical significance was determined by Student's t test (n = 3), and p values are indicated (*, p < 0.05; ***, p < 0.001). Data are shown as mean ± S.E.