Effects of voluntary exercise on blood pressure, angiotensin II, aldosterone, and renal function in two-kidney, one-clip hypertensive rats

Abstract

Spontaneous dynamic exercise promotes sympathoinhibition and decreases arterial pressure in two-kidney, one-clip (2K-1C) hypertensive rats. Renal sympathetic nerves stimulate renin secretion and increase renal tubular sodium reabsorption. We hypothesized that daily voluntary wheel running exercise by 2K-1C rats will decrease mean arterial pressure (MAP), plasma angiotensin II (Ang II), and aldosterone as well as normalize urinary sodium and potassium excretion independent of changes in glomerular filtration rate (GFR). Five-week-old male Sprague Dawley rats underwent sham clipping (Sham) or right renal artery clipping (2K-1C). Rats were randomized to standard caging (SED) or cages with running wheels (EX). After 12 weeks, rats were assigned to either collection of aortic blood for measurement of Ang II and aldosterone or assessment of inulin clearances and excretory function. Running distances were comparable in both EX groups. MAP was lower in 2K-1C EX vs 2K-1C SED rats (P<0.05). Plasma Ang II and aldosterone were significantly higher in 2K-1C SED rats and decreased in 2K-1C EX rats to levels similar to Sham SED or Sham EX rats. Clipped kidney weights were significantly lower in both 2K-1C groups, but GFR and urine flow rates were no different from right and left kidneys among the four groups. Total and fractional sodium excretion rates from the unclipped kidney of 2K-1C SED rats were higher vs either Sham group (P<0.05). Values in 2K-1C EX rats were similar to the Sham groups. Potassium excretion paralleled sodium excretion. These studies show that voluntary dynamic exercise in 2K-1C rats decreases plasma Ang II and aldosterone, which contribute to the lower arterial pressure without deleterious effects on GFR. The effects on sodium excretion underscore the impact of pressure natriuresis despite elevated plasma Ang II and aldosterone in sedentary 2K-1C rats. In contrast, potassium excretion is primarily regulated by circulating aldosterone and distal sodium delivery.

Opposite Effects of Voluntary Physical Exercise on β3-Adrenergic Receptors in the White and Brown Adipose Tissue

“…An increased secretion of aldosterone confirms previous observations in the same strain of rats and the same running protocol [53]. No changes in aldosterone concentrations were observed after prolongation of the running up to twelve weeks [54]. With respect to plasma corticosterone, both enhanced [31,55] and unchanged [53, present study] concentrations were reported following voluntary running exercise.…”

Moderate Physical Exercise Activates ATR2 Receptors, Improving Inflammation and Oxidative Stress in the Duodenum of 2K1C Hypertensive Rats

“…In the present study, the physical exercise was able to mitigate the SBP increase from the second week of training. Similar results were observed by Waldman et al (2017), where the voluntary dynamic exercise on steering wheels provided a considerable reduction in blood pressure in 2K1C rats.…”

Muscle changes with high-intensity aerobic training in an animal model of renal disease

“…Waldman et al 16 observed that hypertensive rats subjected to running exercise exhibit sympathetic inhibition, lower excretion of aldosterone, and consequently lower blood pressure; however, renal function was not affected. Munõz et al 17 found that aerobic exercise decreased the expression of angiotensin II receptors, suppressed the pro-inflammatory and pro-oxidant system, and reduced renal damage.…”