STUDIES ON THE OSMOTIC FRAGILITY OF ERYTHROCYTES INFLUENCED BY A METABOLIC ACIDOSIS / 体力科学

ABSTRACT

By severe physical training, it is confirmed that the destruction of erythrocytes in a trainee happens within one week from the starting point. This destruction of erythrocytes is characterized by the increase in osmotic fragility of erythrocytes to a hypotonic salt solution.<BR>The purpose of this study is to clarify the mechanisms of the increase in osmotic fragility of erythrocytes. The subjects were divided into two groups, athletes and non-athletes, and they were loaded by a treadmill running during three minutes, with speeds from 200 to 250 meters per minutes.<BR>The osmotic fragility of erythrocytes was determined by the Coil Planet Centrifuge System. The measurement of the lactic acid was made by the end point method and the lipid patterns were analyzed, using a flame ionization detector (thinchrograpy) .<BR>The results obtained are as follows<BR>1) After the exercise, the concentration of blood lactate markedly increased and attained to the level of 90mg/% in average.<BR>2) The osmotic fragility of erythrocytes increased in parallel with the elevation of lactate content in the blood.<BR>3) The osmotic fragility of erythrocytes was significantly related with the lactate content (r=0.52, p<0.001), the regression equation of the lactate content (X) and the osmotic fragility of erythrocytes (Y) was Y=0.05x+95.1.<BR>4) After the exercise, the contents of free cholesterol and total phospholipid in the red blood cell markedly decreased in comparison with that before exercise.<BR>5) The osmotic fragility of erythrocytes was significantly related to the content of free cholesterol in the red blood cell (r= -0.45, p<0.02) .<BR>In conclusion, lactic acid may contribute to modify the lipid in the red blood cell and to increase the fragility of the erythrocytes.