Thermal Injury Causes Stimulation of Phospholipase A2 Activity in Mammalian Cells
Heat stress (43°C, 45°C) stimulated phopholipase A2 activity in the two mammalian cell lines investigated: HA-1 hamster fibroblasts and PC-12 rat pheochromocytoma cells. The resultant arachidonic acid (AA) release was of a similar order to that induced by thrombin and bradykinin. Dexamethasone (5 x 10 − 8 M) inhibited by 80%–90% the effect of heat stress on AA release. Heat-induced stimulation of phospholipase A2 activity may be involved both in the direct cytotoxic effects of heat stress and in the inflammatory responses induced by thermal injury.
KeywordsArachidonic Acid Heat Stress Thermal Injury PLA2 Activity Arachidonic Acid Release
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