Effect of Ambient Temperature on Aldose Reductase Activity

Abstract

Erythrocyte aldose reductase activity was measured in diabetic patients and normal controls. The enzyme activity was 2.07 + 0.14 (meas±SEM, U/gHb, n = 45) and 1.11 ±0.12 (n = 34) in diabetic patients and normal controls, respectively (p< 0.0001). Activities of the enzyme correlated well with HbA1 (p < 0.01) but not with fasting plasma glucose. To elucidate the effect of ambient temperature on erythrocyte aldose reductase activity, 9 male students were immersed in water at three different temperatures. After water immersion at 42°C for 10 min, enzyme activity increased by 37.6% (p< 0.01); however, this activity decreased after immersion for 10 min at 39°C (' 52.2%, p<0.01) and 25°C (' 47.0%, p<0.05). Erythrocyte sorbitol content increased by 36.0% (p<0.05) after immersion at 42°C. These changes suggest that heat stress might have some effect on diabetic complications. © 1994, THE JAPAN DIABETES SOCIETY. All rights reserved.