Effect of chronic stress and aerobic exercise on glycemic control in rats

We have previously shown that chronic mild and unpredictable stress (CMS) induced endothelium dysfunction and insulin resistance in rats. Physical exercise is recognized to provide better glycemic control. Thus, the aim of this study was to evaluate the effect of moderate exercise on the response to oral glucose tolerance test (OGTT) of rats submitted to CMS. Male Sprague‐Dawley rats were divided into four groups: 1) Control, 2) Exercise, 3) CMS and 4) Exercise plus CMS (n=7–9). CMS protocol consisted on application of different stressors, 7 days per week (wk) during 3 wk (5, 6 and 7 th wk of protocol). The physical exercise was performed after a period of adaption on the treadmill and consisted of an intensity of 50–70% of the maximal exercise test, 5 days per wk, and 1 hour per day (during 8 wk). Data were analyzed by ANOVA bifatorial (p<0.05). All procedures were approved by Institutional Ethics Committee. Exercise, CMS and Exercise plus CMS presented higher corticosterone plasma level in comparison with Control group (p < 0.05). Exercise (781.1 ± 17,2 mmol × min/L) and Control (842.9 ± 15.5 mmol × min/L) group presented lower area under the curve of glucose during OGTT in comparison with Exercise plus CMS (872.0 ± 12,9 mmol × min/L) and CMS (879.5 ± 11.5 mmol × min/L) group, respectively (p<0.05). These data show that aerobic training has not been able to abolish the impairment of glucose tolerance induced by CMS. Support or Funding Information FAPESP, CAPES, CNPq, FAEPEX‐UNICAMP.