Time Course of Antioxidant and Vascular Function in Rat Aortas Following Acute, Exhaustive Exercise

The purpose of this study was to examine the time course of changes in vascular reactivity and antioxidant status in rat aortas following an acute exhaustive bout of exercise. 7–9 mo old, male, Wistar rats were divided into four groups (n=9/group): sedentary (SED), 6 h post‐exercise (6 h), 24 h post‐exercise, and 48 h post‐exercise. Exercise consisted of one bout of exhaustive treadmill exercise lasting between 30–40 min. Endothelium dependent vasorelaxation was assessed in ring segments of the aorta by constructing an acetycholine (ACh) dose response curve (10 −10 –10 −5 M) in a wire myograph. RESULTS Maximal vasorelexation was impaired in 6 h (67.7±5.4%) compared to SED (76.9±4.1%) and 24 h (80.2+5.5%). EC 50 for ACh at 6 h (9.9±0.1e −7 M) was significantly (p<0.05) greater than SED (4.8±0.1e −7 ) and 24 h (3.9±0.1e −7 ). However, antioxidant capacity was not significantly (P<0.05) increased until 48 h post‐exercise (0.61±0.15 mM) compared to SED (0.14±0.05 mM). These data suggest that acute, exhaustive treadmill exercise results in impaired endothelial dependent vasorelaxation 6 h post‐exercise and returns and possibly improves within 24–48 h during which time antioxidant capacity is increased. Support or Funding Information Borgenicht Program for Aging Studies and Exercise Science This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .