Effect of nutritional status and ozone exposure on Na+/K+ ATPpase and lipid peroxidation in rat brain.

The aim of this study was to analyze the effect of nutritional status and exposure to ozone on the activity of Na+/K+ ATPase and lipid peroxidation in rat brain. Male Wistar rats were fed 7% and 23% protein diets. Two groups were formed for each nutritional status: one group was exposed for 15 successive days to 0.75 ppm of ozone in air and the other was exposed to air. Subsequently, the brain was dissected and cortex, hemispheres, cerebellum and brainstem separately homogenized to measure the activity of thiobarbituric acid reactive substances (TBARS) and ATPase in the presence and absence of ouabain. The activity of Na+/K+ ATPase increased in cerebellum of well-nourished rats exposed to ozone, while total ATPase and TBARS decreased in all studied areas in the malnourished groups. These results suggest that nutritional status and exposure to ozone generate changes in lipid membrane composition, in turn changing the activity of sodium pump with similar consequences for brain metabolism.