NEW FINDINGS: What is the central question of this study? A bout of exercise increases subsequent insulin-stimulated vasodilation; however, the mechanisms remain to be elucidated. A potential role for Angiotensin-(1-7), a vasoactive peptide of the Renin-Angiotensin System, in this effect has not been previously reported. What is the main finding and its importance? We show that Angiotensin-(1-7) through Mas receptor participates in enhanced insulin-induced vasorelaxation after exercise in healthy rats. This new potential role of Angiotensin-(1-7) could help to understand how physical activity improves vascular insulin sensitivity in normal and insulin resistant states. ABSTRACT: Exercise increases insulin-stimulated vasodilation, but the mechanisms involved are unclear. This study was performed to investigate the possible involvement of Angiotensin-(1-7) (Ang-(1-7)), a vasoactive peptide of the Renin-Angiotensin System (RAS), in enhanced vascular insulin sensitivity after a bout of exercise. Male Wistar rats were subjected to swimming for 2.5 h. After exercise, carbachol- or insulin-induced relaxation in aorta was assessed. Prior exercise improved insulin-stimulated vasorelaxation; however, this insulin-sensitizing effect was prevented by the selective Mas receptor (MasR) (Ang-(1-7) receptor) antagonist A779. Carbachol-mediated vascular relaxation was not modified by exercise. These results suggest that Ang-(1-7) acting through MasR participates in the enhancement of vascular insulin sensitivity after an exercise session. This new potential role of Ang-(1-7) could help to understand how exercise improves vascular insulin sensitivity in normal and insulin resistant states. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
NEW FINDINGS: What is the central question of this study? A bout of exercise increases subsequent insulin-stimulated vasodilation; however, the mechanisms remain to be elucidated. A potential role for Angiotensin-(1-7), a vasoactive peptide of the Renin-Angiotensin System, in this effect has not been previously reported. What is the main finding and its importance? We show that Angiotensin-(1-7) through Mas receptor participates in enhanced insulin-induced vasorelaxation after exercise in healthy rats. This new potential role of Angiotensin-(1-7) could help to understand how physical activity improves vascular insulin sensitivity in normal and insulin resistant states. ABSTRACT: Exercise increases insulin-stimulated vasodilation, but the mechanisms involved are unclear. This study was performed to investigate the possible involvement of Angiotensin-(1-7) (Ang-(1-7)), a vasoactive peptide of the Renin-Angiotensin System (RAS), in enhanced vascular insulin sensitivity after a bout of exercise. Male Wistar rats were subjected to swimming for 2.5 h. After exercise, carbachol- or insulin-induced relaxation in aorta was assessed. Prior exercise improved insulin-stimulated vasorelaxation; however, this insulin-sensitizing effect was prevented by the selective Mas receptor (MasR) (Ang-(1-7) receptor) antagonist A779. Carbachol-mediated vascular relaxation was not modified by exercise. These results suggest that Ang-(1-7) acting through MasR participates in the enhancement of vascular insulin sensitivity after an exercise session. This new potential role of Ang-(1-7) could help to understand how exercise improves vascular insulin sensitivity in normal and insulin resistant states. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.