ACTH 1-39 at concentrations of 100-400 nM has no toxic effect on neurons, while ACTH provides protection from excitotoxic neuronal death induced by glutamate (100 μM), NMDA (1 mM), AMPA (50 μM), and kainate (25 μM). ACTH at 400 nM provides substantial protection in each case. ACTH at either 200 or 400 nM protects neurons from quinolinic acid (25 μM). There is also protection by ACTH from cell death induced by 2 μM H2O2, which gives rise to reactive oxygen species (ROS), with significantly more protection at 400 nM ACTH compared to 200 nM. ACTH gives modest protection against rapid release of nitric oxide (NO) by NOC-12 but not slow release by NOC-18. ACTH (200 or 400 nM) protects neurons from cytotoxic effects of staurosporine (10-20 nM), a classic inducer of cell death via apoptosis. ACTH reduces cell death from 80% to 55%.