Effects of One Resistance Exercise Session on Vascular Smooth Muscle of Hypertensive Rats

Abstract

BackgroundHypertension is a public health problem and increases the incidence of cardiovascular diseases.ObjectiveTo evaluate the effects of a resistance exercise session on the contractile and relaxing mechanisms of vascular smooth muscle in mesenteric arteries of NG-nitro L-arginine methyl ester (L-NAME)-induced hypertensive rats.MethodsWistar rats were divided into three groups: control (C), hypertensive (H), and exercised hypertensive (EH). Hypertension was induced by administration of 20 mg/kg of L-NAME for 7 days prior to experimental protocols. The resistance exercise protocol consisted of 10 sets of 10 repetitions and intensity of 40% of one repetition maximum. The reactivity of vascular smooth muscle was evaluated by concentration‑response curves to phenylephrine (PHEN), potassium chloride (KCl) and sodium nitroprusside (SNP).ResultsRats treated with L-NAME showed an increase (p < 0.001) in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) compared to the initial period of induction. No difference in PHEN sensitivity was observed between groups H and EH. Acute resistance exercise reduced (p < 0.001) the contractile response induced by KCl at concentrations of 40 and 60 mM in group EH. Greater (p < 0.01) smooth muscle sensitivity to NPS was observed in group EH as compared to group H.ConclusionOne resistance exercise session reduces the contractile response induced by KCl in addition to increasing the sensitivity of smooth muscle to NO in mesenteric arteries of hypertensive rats.

Effects of a Single Bout of Resistance Exercise in Different Volumes on Endothelium Adaptations in Healthy Animals

“…Furthermore, the role of resistance exercise has been evaluated in the prevention and treatment of several cardiovascular diseases. 20 , 22 However, although the majority of the studies focus on the vascular effects of aerobic exercise, our data are the first that demonstrate the volume-dependent effect on vascular adaptations after a single bout of resistance exercise. Finally, the current findings may contribute to the establishment of safe limits of exercise for patients with endothelial dysfunction and insulin resistance.…”

“…Several studies using a single bout of aerobic 19 or resistance 20 , 21 exercise observed an enhanced vascular relaxation, suggesting an increased NO bioavailability after a session of exercise. Furthermore, the role of resistance exercise has been evaluated in the prevention and treatment of several cardiovascular diseases.…”

Exploring the microcirculatory effects of an exercise programme including aerobic and resistance training in people with limited cutaneous systemic sclerosis

“…There is lack of evidence regarding the effects of resistance exercise on endothelialindependent function. Animal research in N G -nitro-L-arginine-methyl-ester (L-NAME)induced hypertensive rats demonstrated that one resistance exercise session resulted in a reduction in the potassium chloride (KCI)-induced contracting mechanisms by enhancing the vasodilatory sensitivity of the mesenteric artery smooth muscle (Silva et al, 2015). Rats that underwent a resistance exercise session had a reduction in contraction in response to depolarising KCI solutions.…”