Phosphatidic acid, the main product of lipid breakdown through phospholipase D activation, has been implicated in important signal transduction pathways able to influence cell fate in many ways. The purpose of this work was to determine possible effects of phosphatidic acid on neuronal cell death pathways. Here we used cerebellar granular cell cultures and cell death was triggered with either staurosporine or H(2)O(2). Cell viability was quantified by spectrophotometry, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) test. Staurosporine (1-3 microM) or H(2)O(2) (50-800 microM) induced cell death in a dose-dependent manner. Using fluorescent staining (propidium iodide or annexin V-Cy3/6-carboxyfluorescein) we showed that cell death was mostly apoptotic in staurosporine treated cells and mostly non-apoptotic (necrotic) in H(2)O(2) treated cells. Phosphatidic acid was able to increase cell viability in staurosporine-, but not in H(2)O(2) - treated cells. We therefore conclude that phosphatidic acid has neuroprotective potential in neurons exposed to stimuli that trigger apoptosis.