Figure 1. Survival of PC12 cells exposed to Aβ_25–35.

PC12 cells were cultured for 24 and 48 h with 10, 20 and 40 µM Aβ_25–35, respectively. After 24 h in vitro culture, (A) PC12 cells of the normal control group grew well with long neurites. (B) While incubation with 10 µM Aβ_25–35, neurites of cells retracted gradually. (C) When added 20 µM Aβ_25–35 in the medium, the damage to cells was obvious, and some cell debris appeared. (D) The 40 µM Aβ_25–35 strongly insulted cells resulting in loss of more cells. After 48 h with Aβ_25–35, more cells floated in the medium, and cell debris increased. Arrows indicated cell debris. Cell viability was assessed by MTT assay. Absorbance values were presented as mean ± S.E.M. **p < 0.01, compared with the normal control group at 24 h in culture; ^## p < 0.01, compared with the normal control group at 48 h in culture. Data were processed by two-way ANOVA followed by Newman-Keuls test (n = 9). Scale bars: A-D, 100 µm.