Swim training attenuates the adverse remodeling of LV structural and mechanical properties in the early compensated phase of hypertension

• Published in: Life sciences (1973) Vol. 187; pp. 42 - 49
• Main Authors: Locatelli, Jamille, Paiva, Nívia C.N., Carvalho, Sara H.R., Lavorato, Victor N., Gomes, Luis Henrique L.S., Castro, Quênia J.T., Grabe-Guimarães, Andrea, Carneiro, Cláudia M., Natali, Antônio J., Isoldi, Mauro C.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 15.10.2017; Elsevier BV
• Subjects: Animals; Blood pressure; Blood Pressure - physiology; Cardiac remodeling; Cardiomyocytes; Collagen (type III); Collagen Type I - metabolism; Collagen Type III - metabolism; Counterbalances; Electric Stimulation; Heart Rate - physiology; Heart Ventricles - metabolism; Heart Ventricles - pathology; Hypertension; Hypertension - metabolism; Hypertension - pathology; Hypertension - physiopathology; Hypertension - therapy; Hypertrophy; Inflammation; Male; Males; Mechanical properties; Muscle Contraction - physiology; Muscle Relaxation - physiology; Myocytes; Myocytes, Cardiac - pathology; Myocytes, Cardiac - physiology; Pathology; Physical Conditioning, Animal; Physical Therapy Modalities; Rats; Rodents; Spontaneously hypertensive rats; Studies; Swim training; Swimming; Training; Ventricle; Ventricular Remodeling - physiology; Hypertension; Spontaneously hypertensive rats; Cardiomyocytes; Cardiac remodeling; Swim training
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/j.lfs.2017.08.014

Investigate to what extent low-intensity swim training for six weeks counterbalances the adverse remodeling due to the advance of pathological hypertrophy in the left ventricle (LV) structural and mechanical properties in the early compensated phase of hypertension in male SHR. Four-month-old male SHR and Wistar rats were randomly divided into Sed (sedentary) and Ex (exercised) groups. The exercised rats were submitted to a swimming protocol (1h/day, 5times/week, no additional load) for six weeks. LV tissue and isolated myocytes were used to assess structural and mechanical properties. Myocytes were stimulted at frequencies (F) of 1 and 3Hz at 37°C. Exercised SHR showed improvement in cardiovascular parameters compared to sedentary SHR (mean arterial pressure: 13.22%; resting HR: 14.28.%). About structural and mechanical properties, swim training induced a decrease in LV myocyte thickness (10.85%), number of inflammatory cells (21.24%); collagen type III (74.23%) and type I (85.6%) fiber areas; amplitude of single myocyte shortening (47% to F1 and 28.46% to F3), timecourses of shortening (16.5% to F1 and 7.55% to F3) and relaxation (15.31% to F3) compared to sedentary SHR. Six weeks of swim training attenuates the adverse remodeling of LV structural and mechanical properties in the early compensated phase of hypertension in male SHR.