Pathology of left ventricle.

<p>A: Representative short-axis sections of cardiac ventricle stained with Masson-trichrome. Scale bar: 1000 μm. B: Representative short-axis images of myocardium and intramuscular arteries with perivascular and interstitial fibrosis stained with Masson-trichrome. Scale bar: 50 μm. C: Representative short-axis images of myocardium and interstitial fibrosis stained with Masson-trichrome. Scale bar: 50 μm. D: Representative short-axis images of the myocardium stained with hematoxylin-eosin. Scale bar: 50 μm. E: Ratio of fibrosis area/myocardium. F: Mean diameter of cardiomyocytes at 16 weeks of age. Normal salt = NS, Excessively low salt = ELS, *: p<0.05, **: p<0.01.</p

Expression of cardiac tissue ERK1/2, phospho-ERK1/2, p38MAPK, phospho-p38MAPK, HSP27, phospho-HSP27,TGF-ß1.

<p>Normal salt = NS, Excessively low salt = ELS, *: p<0.05, **: p<0.01.</p

Changes in the body weight, heart weight, and heart weight/body weight ratio.

<p>Changes in the body weight, heart weight, and heart weight/body weight ratio.</p

Expression of cardiac tissue renin, (pro) renin receptor, and angiotensinogen and angiotensin II AT1 receptor.

<p>Normal salt = NS, Excessively low salt = ELS, *: p<0.05, **: p<0.01.</p

Time course changes in the systolic blood pressure and heart rate in response to the excessively low salt diet in the WKY and SHR groups.

<p>Time course changes in the systolic blood pressure and heart rate in response to the excessively low salt diet in the WKY and SHR groups.</p

Excessively low salt diet damages the heart through activation of cardiac (pro) renin receptor, renin-angiotensin-aldosterone, and sympatho-adrenal systems in spontaneously hypertensive rats - Fig 4

<p>A: plasma renin activity. B: plasma angiotensin I concentration. C: plasma angiotensin II concentration. D: plasma aldosterone concentration. E: plasma noradrenaline concentration. F: plasma adrenaline concentration.</p

Echocardiographic findings.

<p>A: Interventricular septum (IVS) thickness at 8 and 16 weeks of age. B: LV fractional shortening (FS) at 8 and 16 weeks of age.</p

Proposed mechanism of excessively low salt diet-induced cardiac damage.

<p>Proposed mechanism of excessively low salt diet-induced cardiac damage.</p

Masson-Trichrome staining and hematoxylin-eosin staining of left ventricle.

<p>Representative (a) short-axis sections of cardiac ventricle stained with Masson-Trichrome (Scale bars: 1 mm), (b) short-axis images of the myocardium and intramuscular arteries with perivascular and interstitial fibrosis stained with Masson-Trichrome (Scale bars: 50 μm), (c) short-axis images of the myocardium and interstitial fibrosis stained with Masson-Trichrome (Scale bars: 50 μm) and (d) short-axis images of the myocardium stained with hematoxylin-eosin (Scale bars: 50 μm) at 12 weeks of age in the WKY + normal-salt group (WKY+NS), WKY + high-salt group (WKY+HS), SHR + normal-salt group (SHR+NS) and SHR + high-salt group (SHR+HS). (e) Ratio of myocardial interstitial fibrosis area/ myocardium and (f) Short-axis diameter of cardiomyocytes at 12 weeks of age in the WKY + normal-salt group (WKY+NS), WKY + high-salt group (WKY+HS), SHR + normal-salt group (SHR+NS) and SHR + high-salt group (SHR+HS). Data represent the means ± SEM (n = 7). **: p < 0.01, *: p < 0.05.</p

Expression of cardiac tissue prorenin, renin, (pro)renin receptor, angiotensinogen and angiotensin II AT1 receptor.

<p>Expressions of cardiac tissue (a) prorenin, (b) renin, (c) (pro)renin receptor, (d) angiotensinogen and (e) angiotensin AT1 receptor in the WKY + normal-salt group (WKY+NS), WKY + high-salt group (WKY+HS), SHR + normal-salt group (SHR+NS) and SHR + high-salt group (SHR+HS). Data represent the means ± SEM (n = 7). **: p < 0.01, *: p < 0.05.</p