Effects of Gangliosides, Ouabain and Arachidonic Acid on Glutamate Cytotoxicity in PC12 Cells

The present work shows that gangliosides prevent glutamate cytotoxicity in PC12 cells. Similarly, ouabain (1 and 5 micrograms/ml) protected cells against glutamate-induced toxicity in a dose-dependent manner. The cytoprotection observed with ouabain was not maintained after its association with gangliosides and glutamate. Also, the effects of gangliosides in blocking glutamate cytotoxicity did not persist in the presence of arachidonic acid. The results indicate that a higher degree of sodium pump inhibition is necessary for ouabain cytotoxicity to be manifested, and that a partial enzyme inhibition may actually be protective to glutamate and/or arachidonic acid-induced toxicity in PC12 cells.