Fig. 1

Requirement for AMPK in zinc neurotoxicity. a Microscopic images of Hoechst 33342-stained total nuclei (upper) or TUNEL-positive apoptotic nuclei (lower) of the same field in mouse cortical near-pure neuronal cultures at 12 h after 10 min exposure to 300 μM zinc with or without 20 μM Compound C (CC) or 50 μM metformin (Met). Arrows indicate apoptotic shrunk and fragmented nuclei. Scale bar, 25 μm. b Quantitative data for TUNEL-positive apoptotic cells (left, mean ± SEM, n = 3 cultures) or LDH release (right, mean ± SEM, n = 4 cultures) in near-pure neuronal cultures after 12 h exposure of 300 μM zinc for 10 min with or without CC or Met, or metformin alone. *p < 0.05 and **p < 0.01 compared to zinc-exposed cultures, two-tailed t-test