INFLAMMATORY FACTORS STIMULATE EXPRESSION OF GROUP II PHOSPHOLIPASE A2 IN RAT CULTURED ASTROCYTES : TWO DISTINCT PATHWAYS OF THE GENE EXPRESSION

摘要: Inflammatory factors such as tumor necrosis factor (TNF), interleukin 1 (IL-1), and lipopolysaccharide (LPS) greatly enhance the expression of group II phospholipase A2 (PLA2-II) mRNA, leading to increased secretion PLA2-II enzyme from rat-cultured astrocytes. The potent antiinflammatory agent dexamethasone suppressed induced by LPS. In vivo studies also demonstrated that level mRNA in brain with intravenous injection These results suggest plays important roles inflammatory response. Agents which increase intracellular cAMP concentration did not stimulate themselves but selectively enhanced TNF-induced about 5-fold. Phorbol ester, a well known protein kinase C activator, expression. H-7, inhibitor, inhibited LPS-induced expression, inhibit one. Therefore, we conclude TNF-activated pathway differs LPS-activated one: former is latter involves C.