Effect of Exercise on the Development of Salt-Induced Hypertension in Dahl-S Rats

Savage, Margaret V.; Mackie, Gordon; Bolter, Christopher P.

doi:10.1097/00004872-198606000-00006

Cited by 8 publications

(3 citation statements)

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“…Regular aerobic exercise has been demonstrated to reduce CVD risk in both humans (2,12) and rodent models (9,19,25). Furthermore, both voluntary (9,19) and forced (32,37) aerobic exercise have been shown to attenuate endothelial dysfunction over 4 -14 wk in several rodent models including aging (9), a western-style diet (19), chronic kidney disease (25), and spontaneous hypertension (36). One mechanism responsible for this attenuation is thought to be the upregulation of endogenous antioxidants (9,19,32,37).…”

Section: Introductionmentioning

confidence: 99%

Voluntary wheel running prevents salt-induced endothelial dysfunction: role of oxidative stress

Guers

Kasecky-Lardner

Farquhar

et al. 2019

Journal of Applied Physiology

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Diets high in salt can lead to endothelial dysfunction, a nontraditional risk factor for cardiovascular disease (CVD). Exercise is known to reduce CVD risk; however, it remains unknown whether chronic physical activity can attenuate salt-induced endothelial dysfunction independent of blood pressure (BP) and whether these changes are due to an upregulation in endogenous antioxidants. Eight-week-old Sprague-Dawley rats were fed either a normal (NS; 0.49%)- or a high (HS; 4.0%)-salt diet and further divided into voluntary wheel running (NS-VWR, HS-VWR) and sedentary (NS, HS) groups for 6 wk. BP was measured weekly and remained unchanged within groups ( P = 0.373). Endothelium-dependent relaxation (EDR) was impaired in the femoral artery of HS compared with NS (38.6 ± 4.0% vs. 65.0 ± 3.6%; P = 0.013) animals, whereas it was not different between NS and HS-VWR (73.4 ± 6.4%; P = 0.273) animals. Incubation with the antioxidants TEMPOL ( P = 0.024) and apocynin ( P = 0.013) improved EDR in HS animals, indicating a role for reactive oxygen species (ROS). Wheel running upregulated the antioxidant superoxide dismutase-2 (SOD-2) ( P = 0.011) under HS conditions and lowered NOX4 and Gp91-phox, two subunits of NADPH oxidase. Wheel running elevated phosphorylated endothelial nitric oxide synthase (eNOS) ( P = 0.014) in HS-fed rats, demonstrating a role for physical activity and eNOS activity under HS conditions. Finally, there was a reduction in EDR ( P = 0.038) when femoral arteries from NS-VWR animals were incubated with TEMPOL or apocynin, suggesting there may be a critical level of ROS needed to maintain endothelial function. In summary, physical activity protected HS-fed rats from reductions in endothelial function, likely through increased SOD-2 levels and reduced oxidative stress. NEW & NOTEWORTHY Our data suggest that voluntary wheel running can prevent impairments in endothelium-dependent relaxation in the femoral artery of rats fed a high-salt diet. This appears to be independent of blood pressure and mediated through a decrease in expression of NADPH oxidases as a result of physical activity. These data suggest that increased chronic physical activity can protect the vasculature from a diet high in salt, likely through a reduction in oxidative stress.

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Section: Introductionmentioning

confidence: 99%

Voluntary wheel running prevents salt-induced endothelial dysfunction: role of oxidative stress

Guers

Kasecky-Lardner

Farquhar

et al. 2019

Journal of Applied Physiology

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“…The effects of Ex on blood pressure in Dahl-S rats are controversial. Some studies report that Ex suppressed the progression of hypertension in Dahl-S rats (27,28); others report that Ex did not alter blood pressure (29,30). Studies have also reported that Ex improved the HS-induced heart failure and survival rate in Dahl-S rats without changing blood pressure (31,32).…”

Section: Discussionmentioning

confidence: 99%

Effects of Exercise Training on the Renin–Angiotensin System in the Kidneys of Dahl Salt-Sensitive Rats

Sakuyama

Ogawa

et al. 2022

Medicine &Amp; Science in Sports &Amp; Exercise

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Purpose: Exercise training (Ex) has antihypertensive and renal protective effects; however, the precise mechanisms remain unclear. The renal renin-angiotensin system (RAS) plays a vital role in renal function and pathology. Therefore, we investigated the effects of Ex on the renal RAS components in Dahl salt-sensitive (Dahl-S) rats. Methods: Male Dahl-S rats were divided into four groups: normal salt diet + sedentary, normal salt diet + Ex, high-salt diet (HS, 8% NaCl) + sedentary, and HS + Ex. Treadmill running was performed for 8 wk in the Ex groups. Results: Ex attenuated the HS-induced renal dysfunction and glomerular injury without causing blood pressure alterations. HS increased urinary excretion of both total and intact angiotensinogen. Ex decreased the HS-induced increased urinary excretion of total angiotensinogen. However, it did not change the HS-induced urinary excretion of intact angiotensinogen, indicating reduced intact angiotensinogen cleaving. Ex restored the HS-induced increased angiotensinogen and angiotensin II type 1 receptor expressions in the outer medulla and the HS-induced increased angiotensin-converting enzyme expression in the cortex. Ex restored the HS-induced decreased renin expression in the cortex and outer medulla, and the HS-induced decreased angiotensin-converting enzyme 2, angiotensin II type 2 receptor, and Mas receptor expressions in the outer medulla. Conclusions: Ex attenuates HS-induced renal dysfunction, glomerular injury, and renal RAS dysregulation in Dahl-S rats.

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“…Ex with treadmill for 12 wk did not affect SBP in female DS rats fed high salt (33). However, Ex with treadmill for 8 wk reduced blood pressure in male DS rats who received high salt (34,35). In addition, Ex with treadmill for 8 wk attenuated the high salt-induced glomerular sclerosis in DS rats, although it did not affect blood pressure (20,22).…”

Section: Discussionmentioning

confidence: 99%

Exercise Training Prevents High Fructose-Induced Hypertension and Renal Damages in Male Dahl Salt-Sensitive Rats

Qiu

et al. 2022

Medicine &Amp; Science in Sports &Amp; Exercise

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IntroductionHigh-fructose diet (HFr) causes metabolic syndrome, and HFr-induced hypertension and renal damage are exaggerated in Dahl salt-sensitive (DS) rats. Exercise training (Ex) has antihypertensive and renal protective effects in rats fed HFr; however, there has been little discussion about the DS rats, which exhibit metabolic disturbances. This study thus examined the effects of Ex on DS rats fed HFr.MethodsMale DS rats were divided into three groups. The control group was fed a control diet, and both the HFr group and the HFr–Ex group were fed an HFr (60% fructose). The HFr–Ex group also underwent treadmill running (20 m·min−1, 60 min·d−1, 5 d·wk−1). After 12 wk, renal function, histology, and renin–angiotensin system were examined.ResultsHFr increased blood pressure, urinary albumin, and creatinine clearance, and Ex inhibited these increases. HFr induced glomerular sclerosis, podocyte injury, afferent arteriole thickening, and renal interstitial fibrosis, and Ex ameliorated them. HFr reduced plasma renin activity, and Ex further reduced the activity. HFr also increased the expression of angiotensinogen, renin, angiotensin-converting enzyme (ACE), and angiotensin II type 1 receptor, and Ex restored the ACE expression to the control levels. HFr decreased the expression of ACE2, angiotensin II type 2 receptor, and Mas receptor, and Ex restored the ACE2 and Mas receptor expressions to the control levels and further decreased the angiotensin II type 2 receptor expression. HFr increased the ACE activity and decreased the ACE2 activity, and Ex restored these activities to the control levels.ConclusionsEx prevents HFr-induced hypertension and renal damages in DS rats. The changes in renal renin–angiotensin system may be involved in the mechanism of the antihypertensive and renal protective effects of Ex.

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Effect of Exercise on the Development of Salt-Induced Hypertension in Dahl-S Rats

Cited by 8 publications

References 0 publications

Voluntary wheel running prevents salt-induced endothelial dysfunction: role of oxidative stress

Voluntary wheel running prevents salt-induced endothelial dysfunction: role of oxidative stress

Effects of Exercise Training on the Renin–Angiotensin System in the Kidneys of Dahl Salt-Sensitive Rats

Exercise Training Prevents High Fructose-Induced Hypertension and Renal Damages in Male Dahl Salt-Sensitive Rats

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