Ascorbate neurotoxicity in cortical cell culture.

Ascorbate (vitamin C) is believed to act as a neuromodulator that facilitates the release of neurotransmitters and inhibits neurotransmitter binding to receptors, including dopamine and N-methyl-D-aspartate receptors. Extracellular levels of ascorbate are known to reach the low millimolar range after ischemic brain injury. This study shows that treatment of cultured cortical neurons with micromolar to low millimolar ascorbate first inhibits total protein synthesis and then results in late neuronal death. Astrocytes are much less vulnerable to ascorbate than neurons. Ascorbate may exacerbate neuronal and glial damage after brain ischemia, and it may play a pathological role in other neurological diseases.