Fig. 7

ER cisternal stacks (arrows in b, c) were absent in neuronal somas under control conditions (a), but appeared upon stimulation, such as depolarization with high K⁺ (90 mM, 3 min, b) or treatment with NMDA (50 μM, 2 min, c). Samples were from the CA1 region of the hippocampal slice cultures. Consistent with Fig. 3, the nuclei of these pyramidal neurons appeared non-clustered under control conditions (a), but the chromatin aggregated into dark clusters upon stimulation (b, c). Additionally, mitochondria (m) appeared swollen upon stimulation (b, c). Scale bar = 0.5 μm