Exercise training attenuates angiotensin II‐induced vasoconstriction in the aorta of normotensive but not hypertensive rats

Abstract

This study investigated the effects of both acute exercise and training on the Ang II-induced vasoconstriction in aorta of normotensive (two-kidney; 2K) and two-kidney-one-clip (2K1C) hypertensive rats, focusing on endothelial mechanisms related to nitric oxide (NO) and prostanoids.Aorta rings of 2K and 2K1C male Wistar rats, sedentary and trained, killed at rest and after acute exercise, were challenged with Ang II in either the absence or the presence of PD 123,319, a selective angiotensin receptor subtype 2 (AT 2 R) antagonist; N -nitro-L-arginine methyl ester (L-NAME), a non-selective inhibitor of nitric oxide synthase; indomethacin, a non-selective inhibitor of cyclooxygenase; or Tiron, an analogue of superoxide dismutase. Aortas of sedentary and trained animals studied at rest were also submitted to histomorphometric analysis. Exercise training reduced the Ang II-induced vasoconstriction in aorta of 2K but not of 2K1C animals. This reduction of Ang II response in aortas of 2K animals was not found after endothelial removal or treatment with PD 123,319 or L-NAME. These results suggest that exercise training improves the modulation of Ang II-induced vasoconstriction in aorta of 2K animals, by endothelium-derived NO released due to the activation of AT 2 R. No exercise-induced change of Ang II response occurred in 2K1C animals, except in the presence of Tiron, which was evidence for reduction of such responses only in resting trained 2K1C animals. In 2K1C animals, NO modulation of Ang II-induced vasoconstriction might be suppressed by local oxidative stress. Moreover, exercise training slightly reduced the media layer thickness in the aortas of the 2K1C, but not 2K animals, which may indicate cardiovascular protection of these animals. K E Y W O R D Sangiotensin II, aorta, exercise 1 wileyonlinelibrary.com/journal/eph Experimental Physiology. 2020;105:732-742.

Effect of treatment with carvacrol and aerobic training on cardiovascular function in spontaneously hypertensive rats

“…The effects of this combination (ExerCarv) were sufficient to normalise BP, providing a greater magnitude of reduction than any of the other treatments. Understanding that aerobic exercise promotes systemic adaptations, such as decreased vascular tension, by reducing the influx of calcium into the cell (Chen et al., 2019; Qiu et al., 2018), and increased production of nitric oxide (Blanco‐Rivero et al., 2013), as well as neurohormonal adaptations, via decreased sympathetic hyperactivity and increased baroreflex sensitivity (Moraes‐Silva et al., 2010; Dias et al., 2017; Ferreira‐Junior et al., 2019), it can also decrease the synthesis of angiotensin II and its vascular effects (Almeida et al., 2020; Magalhães et al., 2020; Oliveira et al ., 2020). We believe that these systemic adaptations to exercise, combined with the reduction of vascular tension caused by blocking calcium channels with carvacrol, may have attributed to the pronounced effects observed in the ExerCarv group.…”