Effect of cyclooxygenase inhibition on brain cell membrane lipid peroxidation during hypoxia in newborn piglets.
Kľúčové slová
Abstrakt
To test the hypothesis that indomethacin, an inhibitor of cyclooxygenase, reduces free radical-induced brain cell membrane changes during cerebral hypoxia, we determined levels of brain cell membrane lipid peroxidation products and Na+,K(+)-ATPase activity as indicators of free radical production and membrane function, respectively, in 29 newborn piglets divided into 4 groups. Eight saline- and 4 indomethacin-treated normoxic animals served as controls; 8 saline-pretreated piglets and 9 piglets pretreated with indomethacin were exposed to hypoxic hypoxia for 60 min. Cerebral hypoxia was documented using 31P-NMR spectroscopy. In saline-pretreated hypoxic animals Na+,K(+)-ATPase activity decreased significantly and levels of membrane lipid peroxidation products increased significantly compared to normoxic controls. Indomethacin pretreatment prevented the hypoxia-induced increase in membrane lipid peroxidation products but had no effect on the decrease in Na+,K(+)-ATPase activity. Thus the apparent reduction in free radical production by indomethacin pretreatment did not prevent the hypoxia-induced change in Na+,K(+)-ATPase activity.