Vascular adaptation to aerobic exercise: A new experimental approach

Purpose. - The purpose of this preliminary study is to access whether moderate-intensity exercise training is associated with a chronic modification of the cellular response to a mechanical stress-induced with hypo-osmotic shock (regulatory volume decrease process) of 80 mosmoles.kg(-1). Materials and methods. - Wistar Kyoto male rats were subjected to a treadmill training protocol (Tr) (60 min per day, 5 days per week, 8 weeks, 15 degrees incline, 20m.min(-1)) or not (Sed). The rats were then sacrified and endothelial cells isolated from the thoracic and abdominal aortas. Results. - No significant group effect of hypo-osmotic shock was found. A RVD process was observed in cells from the Sed group, cell volume being significantly decreased 20 minutes after the shock (75% of initial volume). However, no RVD was found in cells from the Tr group. These preliminary results suggest that the increase in endothelial cell volume induced by hypo-osmotic shock is modified by chronic exercise as is the subsequent physiological response (RVD process). Therefore, we conclude that isolated endothelial cells from trained rat arteries would provide a good model to assess the effects of chronic exercise on cellular signaling. (C) 2014 Elsevier Masson SAS. All rights reserved.