Effects of temperature on arachidonic acid-induced cellular edema and membrane perturbation in rat brain cortical slices.
The effects of temperature on arachidonic acid-induced cellular edema in the first cortical brain slices of rats were studied. Incubation of the cortical slice in arachidonic acid at 37 degrees C induced cellular swelling, and increased intracellular Na+ and lactic acid contents concomitant with decreased intracellular K+. When the incubation temperature was reduced these changes were reduced in severity. The uptake of [3H]arachidonic acid in cortical slices was temperature-dependent. The incorporation of [3H]arachidonic acid into various lipid fractions was further studied by HPLC. The majority of [3H]arachidonic acid was incorporated into triacylglycerol and phosphatidylinositol (PI), but the incorporation of [3H]arachidonic acid into PI was temperature-dependent, unlike that into other phospholipids and neutrolipids. Further, cortical (Na+ + K+)-ATPase activity was inhibited whereas its subunit K+-activated p-nitrophenyl-phosphatase was activated by arachidonic acid at various incubation temperatures. The effects of arachidonic acid on these enzymes is similar to that of thimerosal, a lipid removal agent. These data suggest that both temperature and arachidonic acid play an important role in the development of cellular edema associated with membrane perturbation and inactivation of (Na+ + K+)-ATPase activity.
D009597:4-Nitrophenylphosphatase / Q000378:metabolism; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids; D001929:Brain Edema / Q000139:chemically induced* / Q000473:pathology; D002462:Cell Membrane / Q000201:enzymology; D002540:Cerebral Cortex / Q000201:enzymology / Q000473:pathology*; D008297:Male; D011188:Potassium / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013696:Temperature
D001095:Arachidonic Acids; D016718:Arachidonic Acid; D009597:4-Nitrophenylphosphatase; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium