TD-induced ER stress in iCell Neurons. A. iCell neurons were treated with amprolium (0 or 1 mM). At specified times after the treatment, the lysates of the iCell neuron samples were collected. The expressions of GRP78, XBP-1, CHOP, p-eIF2α, caspase-12, and ATF6 were determined by immunoblotting. B. The relative amounts of GRP78, CHOP, p-eIF2α, cleaved caspase-12, and ATF6 were measured microdensitometrically and normalized to the expression of actin. The experiment was replicated three times, and the results were expressed as the mean ± SEM. *p < 0.05, statistically significant difference from untreated control groups.