Figure 3.

Acute energy inhibition increases BACE1 protein levels in the brains of C57/B6 mice. A–F, Two- to 3-month-old C57/B6 mice were given a single intraperitoneal injection of 18 U/kg insulin, 1 g/kg 2DG, 100 mg/kg 3NP, 30 mg/kg KA, or vehicle and were then allowed to recover for 4 h (A, B), 2 d (C, D) or 7 d (E, F). Brains were then isolated and homogenized, and samples (15μg/lane) were subjected to immunoblot analysis for BACE1 protein using anti-BACE1 antibody PA1–757. Blots were stripped and reprobed with anti-β-actin antibody as a loading control. A, C, E, Representative BACE1 (top panels) and β-actin (bottom panels) immunoblots for the various treatments and recovery times are shown. B, D, F, The intensities of BACE1 band signals were quantified on a PhosphorImager (Eastman Kodak), normalized against the β-actin immunosignals for each sample, and then expressed as percentages of the mean of the vehicle control for a given recovery time. Note that the energy-inhibitor treatments elevated cerebral BACE1 protein levels to 125–150% of vehicle control values for all recovery times (*p < 0.05, **p < 0.01, and ***p < 0.001, one-way ANOVA with Newman-Keuls multiple-comparison test). A–D, Data represent mean ± SEM; n = 9 mice/treatment (A, B), n = 5 mice/treatment (C, D), and n = 4 mice/treatment (E, F).