(A) Primary neurons were incubated for 30min in conditioned media from astrocytes cultured in DMEM/BSA (CM-B) or in palmitate (CM-P) and the activity of calpain was measured. (B) m-calpain level in primary neurons. Primary neurons were incubated with CM-B (control) or CM-P for 30min and the cells were lysed. m-calpain levels were detected by western blot. Actin was used as a loading control. (C, D) Spectrin levels in neurons. Primary neurons were incubated with CM-B (control) or CM-P for 30min. Calpeptin (20μM) or PD150606 (100μM), specific inhibitors of calpain, was used to pre- and co-treated the neurons with CM-P for 30min individually. Then the cells were lysed and representative western blot results of spectrin are shown in (C). The results were normalized to control (CM-B). *p<0.05, **p<0.01, ***p<0.001.