Dual action of lysophosphatidic acid in cultured cortical neurons: survival and apoptogenic.

The effect of lysophosphatidic acid (LPA), with a wide range of its different concentrations, upon cultured mouse cortical neurons was assessed by electrophoresis of DNA fragments, HO33342 and TUNEL stainings, and also by ultrastructural examination at times. The results showed that administration of LPA at lower concentrations (0.1-30 micromol/L) dose-dependently protected cortical neurons from apoptosis that was induced by deprivation of serum from the cultural medium, while 50 micromol/L or higher concentrations of LPA failed to show this effect; and moreover, the concentrations higher than 50 micromol/L induced apoptosis in neurons cultured in serum-containing complete medium. These results suggest that a moderate concentration of LPA may play as a survival factor in apoptotic cortical neurons, while an excessive level of LPA induces apoptosis in neurons cultured in complete medium.