Exercise training ameliorates adrenergic control in spontaneously hypertensive rats.

The goal of this study was to examine vascular control after sympathetic stimulation by tyramine infusion in hypertensive rats submitted to swimming training. To this end, male rats were assigned to the following groups: sedentary (SN) and trained normotensive (TN), sedentary (SH) and trained hypertensive (TH). Arterial pressure (AP), heart rate (HR), HR variability (HRV), AP variability (APV), and cardiac autonomic function were recorded.

Low levels of dehydroepiandrosterone sulfate are associated with the risk of developing cardiac autonomic dysfunction in elderly subjects.

Objective: To assess the relationships between serum dehydroepiandrosterone sulfate (DHEA-S) levels and heart rate variability (HRV) among different age groups.

Subjects And Methods: Forty-five healthy men were divided into 3 groups: young age (YA; 20-39 yrs; n = 15), middle age (MA; 40-59 yrs; n = 15) and old age (OA; ≥ 60 yrs; n = 15). Hemodynamic parameters, linear analyses of HRV and concentrations of cortisol and DHEA-S were measured at rest.

Exercise Training Attenuates Sympathetic Activity and Improves Morphometry of Splenic Arterioles in Spontaneously Hipertensive Rats.

Background: Alterations in the structure of resistance vessels contribute to elevated systemic vascular resistance in hypertension and are linked to sympathetic hyperactivity and related lesions in target organs.

Objective: To assess the effects of exercise training on hemodynamic and autonomic parameters, as well as splenic arteriolar damages in male Wistar Kyoto (WKY) and Spontaneously Hypertensive Rats (SHR).

Methods: Normotensive sedentary (WKYS) and trained (WKYT) rats, and hypertensive sedentary (SHRS) and trained (SHRT) rats were included in this study.

Long-term anabolic steroids in male bodybuilders induce cardiovascular structural and autonomic abnormalities.

Objective: The aims of this study were to examine the hypothesis that users of anabolic androgenic steroids (AAS) would have cardiac autonomic disorders and that there is a correlation between sympathetic modulation, high blood pressure (BP) and alterations to cardiac dimensions.

Methods: Forty-five male subjects were enrolled in the study. They were categorized into three groups comprising bodybuilders actively using AAS (AAS users; n = 15), bodybuilders who had never used AAS (nonusers; n = 15) and age-paired healthy sedentary controls (n = 15).

Exercise training improves hypertension-induced autonomic dysfunction without influencing properties of peripheral cardiac vagus nerve.

We examined the vagal transfer function of autonomic heart rate (HR) control in anesthetized sedentary and exercise-trained Spontaneously Hypertensive Rats (SHR). To this end, male SHR and Wystar-Kyoto (WKY) rats with 48-50weeks of age-old were divided into 4 groups: sedentary (SHR, n=12) and trained (SHR, n=14) hypertensive rats, sedentary (WKY, n=13) and trained (WKY, n=13) normotensive rats. The trained groups were submitted to swimming protocol for 9weeks.