Angiotensin-(1-7) attenuates hypertension in exercise-trained renal hypertensive rats

• Published in: American journal of physiology. Heart and circulatory physiology 2012-06, Vol.302 (11), p.H2372-H2380
• Main Authors: Shah, Amin, Oh, Young-Bin, Lee, Sun Hwa, Lim, Jung Min, Kim, Suhn Hee
• Format: Article
• Language: English
• Subjects: ACE inhibitors; Angiotensin I - pharmacology; Angiotensin I - therapeutic use; Animals; Antihypertensive Agents - pharmacology; Antihypertensive Agents - therapeutic use; Blood Pressure - drug effects; Blood Pressure - physiology; Cardiotonic Agents - pharmacology; Cardiotonic Agents - therapeutic use; Disease Models, Animal; Heart Ventricles - metabolism; Heart Ventricles - pathology; Heart Ventricles - physiopathology; Hypertension; Hypertension, Renal - physiopathology; Hypertension, Renal - prevention & control; Hypertrophy, Left Ventricular - pathology; Hypertrophy, Left Ventricular - prevention & control; Kidney - physiopathology; Kidney - surgery; Male; Nitric Oxide Synthase Type III - metabolism; Peptide Fragments - pharmacology; Peptide Fragments - therapeutic use; Phosphorylation; Physical Conditioning, Animal - physiology; Proteins; Rats; Rats, Sprague-Dawley; Receptor, Angiotensin, Type 2 - metabolism; Rodents; Surgical Instruments; Swimming - physiology
• ISSN: 0363-6135; 1522-1539
• DOI: 10.1152/ajpheart.00846.2011

Angiotensin-(1-7) [ANG-(1-7)] plays a counterregulatory role to angiotensin II in the renin-angiotensin system. In trained spontaneous hypertensive rats, Mas expression and protein are upregulated in ventricular tissue. Therefore, we examined the role of ANG-(1-7) on cardiac hemodynamics, cardiac functions, and cardiac remodeling in trained two-kidney one-clip hypertensive (2K1C) rats. For this purpose, rats were divided into sedentary and trained groups. Each group consists of sham and 2K1C rats with and without ANG-(1-7) infusion. Swimming training was performed for 1 h/day, 5 days/wk for 4 wk following 1 wk of swimming training for acclimatization. 2K1C rats showed moderate hypertension and left ventricular hypertrophy without changing left ventricular function. Chronic infusion of ANG-(1-7) attenuated hypertension and cardiac hypertrophy only in trained 2K1C rats but not in sedentary 2K1C rats. Chronic ANG-(1-7) treatment significantly attenuated increases in myocyte diameter and cardiac fibrosis induced by hypertension in only trained 2K1C rats. The Mas receptor, ANG II type 2 receptor protein, and endothelial nitric oxide synthase phosphorylation in ventricles were upregulated in trained 2K1C rats. In conclusion, chronic infusion of ANG-(1-7) attenuates hypertension in trained 2K1C rats.