THE EFFECT OF HIGH-ALTITUDE AND CALORIC RESTRICTION ON REACTIVE CARBONYL DERIVATIVES AND ACTIVITY OF GLUTAMINE-SYNTHETASE IN RAT-BRAIN

Both exposure to high altitude (HA) and caloric restriction (CR) may i nfluence free radical generation. The aim of the present study was to evaluate the effects of 4 wk chronic exposure to 4, 000m of HA and CR (60% of CR of control (C) rats) on protein oxidation in brain. Eightee n rats with similar body mass were assigned to CR, HA and C rats. Reac tive carbonyl derivatives (RCD), marker of protein oxidation, were mea sured by Western blot. In addition, the activity and protein content o f glutamine syntethase (GS) were determined. The body mass of C rats w as significantly higher (P < 0.001) than that of HA and CR groups. The quantified signal intensity of RCD was significantly stronger in C ra ts than in HA and CR rats. The activity of GS was significantly increa sed in CR rats, while the protein content of GS was decreased in HA ra ts compared to C group. The data suggest that both HA and CR decreases the accumulation of RCD in the brain, however the mechanism of the de crease seems to be different during HA and CR.