The Effect Of Phosphatidic Acid On Hippocampal Neurons

The serious diseases relational with memory have become widespread and affeced the elderly ability of living. Hippocampus is a key component of learning and memory. The damage of medicines to neurons in the hippocampus was one of most important reasons for the decrease in memory lead. After hippocampus were injured, cerebral atrophy came out. Breakthrough has been made under the joint effort of physicians, but there are many pressing research issues in the choice and the treatment of operative medicines.ActinomycinD is one of parts of anti-cancer drugs; Sodium Nitrite as a kind of oxidation food addiitive can produce varying degrees of cerebral hypoxia. Phosphatidic acid (PA) as one of components on cytomembranes should evoke a rapid rise in the intracellular Ca2+ through release of intracellular Ca2+ stores and influx of extracellular Ca2+. But along with too much Ca2+ increase in cells, calcium overload comes out.But there has been no reports about the effect of PA on hippocampal neurons so far. We used actinomycin D and NaNO2 to stimulate cells, and researched the effect of PA on injured hippocampal neurons on cell level.Objetive: find out the optimal concentration of PA that could evoke a rapid rise in the intracellular Ca2+ through release of intracellular Ca2+ stores and influx of extracellular Ca2+. Research the effect of this concentration of PA on neuronal cells stimulated by actinomycin D or NaNO2 .Methods: find out the optimal concentration of PA that could evoke a rise in the intracellular Ca2+. Rat hippocampal neurons in culture medium were exposed to different concentrations and incubation time of actinomycin D or NaNO2. By examining morphologies of cells detected with acridine orange (AO) staining, different changes of fluorescences of Ca2+ observed with Fluo3-AM, and caspase-3 activity assayed with enzyme linked immunosorbent assay (ELISA) kit, we found out the role of the above concentration of phosphatidic acid (PA) on injured cells.Results: 0.05 mg/L actinomycin D or 20μmol/L NaNO2 did induce apoptosis for hippocampal neurons. 10μg/ml PA could better evoke a rapid rise in the intracellular Ca2+. But along with too much Ca2+ increase in cells, PA aggravated the damnification to cells.Conclusion:1) For normal hippocampal neurons, 10ug/ml PA could evoke a rapid rise in the intracellular Ca2+ observed with Fluo3.2) Actinomycin D at a certain concentration of 0.05 mg/L could induce rat hippocampal neurons apoptosis by stimulating nerve cells 4h. In this study, it is reliable to establish actinomycin D–induced apoptosis model for hippocampal neurons..3) The results of 20umol/L NaNO2 incubation 12h could establish NaNO2–induced a injure model for hippocampal neurons.4) PA aggravated the damnification to injured hippocampal neurons.