Title: Methylmercury stimulates arachidonic acid release and cytosolic phospholipase A2 expression in primary neuronal cultures.
Authors: Shanker, Gouri; Hampson, Robert E; Aschner, Michael
Published In Neurotoxicology, (2004 Mar)
Abstract: Cytosolic phospholipase A2 (cPLA2) plays an important role in the stimulus-dependent hydrolysis of sn-2 ester bond from membrane phospholipids, releasing arachidonic acid (AA), which along with its metabolites is involved in a number of regulatory functions. The present study examined the effect of methylmercury (MeHg; 0, 2.5, 5.0 microM) on cPLA2 activation in primary hippocampal neurons by assessing the release of 3H-AA. A significant increase in AA release was observed in cultures treated with 5 microM MeHg (10, 30, 60 and 120 min). This effect was due to neuronal cPLA2 activation, since it was completely abolished by arachidonyl trifluoromethyl ketone (AACOCF3), a specific inhibitor of cPLA2. Additional studies confirmed, by means of western blot analysis, that MeHg (5.0 and 10 microM; 16h) potently increases neuronal cPLA2 protein expression. These results suggest that cPLA2-stimulated hydrolysis and release of AA are potential mediators of MeHg-induced neurotoxicity.
PubMed ID: 15019302
MeSH Terms: Animals; Arachidonic Acid/metabolism; Arachidonic Acid/secretion*; Cells, Cultured; Cytosol/drug effects*; Cytosol/metabolism; Cytosol/secretion; Hippocampus/drug effects; Hippocampus/metabolism; Hippocampus/secretion; Methylmercury Compounds/pharmacology*; Neurons/drug effects*; Neurons/metabolism; Neurons/secretion; Phospholipases A/biosynthesis*; Phospholipases A/genetics; Phospholipases A2; Rats