Differential nitric oxide sensitivity in motor neurons and oligodendrocytes: Implication for central nervous system diseases.

摘要

Nitric oxide (NO) is a free radical gas that is utilized by the central nervous system (CNS) for a variety of cellular functions at physiological concentrations. However at high concentrations, NO is highly reactive and can combine with other free radicals, such as superoxide to form reactive nitrogenous species (RNS). The formation of RNS results in nitrooxidative damage, evidence of which is detected in diseases such as Amyotrophic Lateral Sclerosis (ALS) or Multiple Sclerosis (MS). We exposed CNS cell types, oligodendrocytes and motor neurons, to a range of NO doses (physiological to pathological). We observed that oligodendrocytes were more resistant to NO than were motor neurons. Nitrotyrosine (3NY) formation is increased in response to cytotoxic NO in motor neurons as compared to oligodendrocytes. These findings elucidate the possibility that there is a NO-mediated disruption of the vital interplay between oligodendrocytes and motor neurons, culminating in MS or ALS etiology.