Effect of gender on training-induced vascular remodeling in SHR

Abstract

There is accumulating evidence that physical inactivity, associated with the modern sedentary lifestyle, is a major determinant of hypertension. It represents the most important modifiable risk factor for cardiovascular diseases, which are the leading cause of morbidity and mortality for both men and women. In addition to involving sympathetic overactivity that alters hemodynamic parameters, hypertension is accompanied by several abnormalities in the skeletal muscle circulation including vessel rarefaction and increased arteriole wall-to-lumen ratio, which contribute to increased total peripheral resistance. Low-intensity aerobic training is a promising tool for the prevention, treatment and control of high blood pressure, but its efficacy may differ between men and women and between male and female animals. This review focuses on peripheral training-induced adaptations that contribute to a blood pressure-lowering effect, with special attention to differential responses in male and female spontaneously hypertensive rats (SHR). Heart, diaphragm and skeletal muscle arterioles (but not kidney arterioles) undergo eutrophic outward remodeling in trained male SHR, which contributed to a reduction of peripheral resistance and to a pressure fall. In contrast, trained female SHR showed no change in arteriole wall-to-lumen ratio and no pressure fall. On the other hand, training-induced adaptive changes in capillaries and venules (increased density) were similar in male and female SHR, supporting a similar hyperemic response to exercise.

Moderate Treadmill Exercise Training Improves Cardiovascular and Nitrergic Response and Resistance to Trypanosoma cruzi Infection in Mice

“…Moderate intensity and long duration exercises, such as swimming and running, have been shown to be efficient non-pharmacological therapies in promoting cardiovascular health by increasing systolic volume (Melo et al, 2003), capillary angiogenesis (Amaral and Michelini, 2011), bradycardia (Mastelari et al, 2011; Raquel Hde et al, 2016), cardiac hypertrophy (Souza et al, 2007) and baroreflex gain (Brum et al, 2000). Due to the positive effects of the running for cardiovascular rehabilitation, treadmill physical training protocols have been applied as allies in the treatment of arterial hypertension (Brum et al, 2000) (Veras-Silva et al, 1997) and heart failure (Krieger et al, 2001; Ichige et al, 2016), among others.…”

Short-Term Esmolol Improves Coronary Artery Remodeling in Spontaneously Hypertensive Rats through Increased Nitric Oxide Bioavailability and Superoxide Dismutase Activity

“…However, esmolol produced eutrophic outward remodeling (decreases in wall thickness to inner diameter ratio), which is associated with a decrease in vascular resistance and, consequently, a decrease in arterial pressure [29]. …”

Time-Dependent Effects of Training on Cardiovascular Control in Spontaneously Hypertensive Rats: Role for Brain Oxidative Stress and Inflammation and Baroreflex Sensitivity

“…After an acclimatization period, SHR rats were preselected for their ability to walk/run on a treadmill (KT-300, Inbramed, Porto Alegre, Brazil; 5–10 sessions from 0.3 to 0.7 km/h, 0% grade, 5–10 min/day). Progressive maximal exercise tests on the treadmill (beginning at 0.3 km/h, with increments of 0.3 km/h every 3 min until exhaustion) [17], [18], [24] were used to allocate SHR with similar physical capacity to trained (T) and sedentary (S) protocols. Low-intensity T (50–60% of maximal exercise capacity, 0% grade, performed 5 days/week, 1 hour/day for 8 weeks) was similar to that used previously [17], [18], [24].…”

“…Experimental evidence has shown that T promotes several cardiovascular benefits [15]–[17] and improves both baroreflex function and autonomic control [18], [19]. T reduces RAS activity, oxidative stress and PICs secretion within autonomic brain areas of spontaneously hypertensive rats (SHR) [20], [21], which is the best experimental model of essential hypertension.…”