Tissue angiotensin II concentration in the heart and kidneys in transgenic Tsukuba hypertensive mice

Tsukuba hypertensive mice (THM) are transgenic mice carrying both human renin and angiotensinogen genes, and possessing an overexpressing human renin-angiotensin system. The aim of this study is to evaluate the angiotensin II concentration in the heart and kidney in THM. Twenty-week-old male THM and control C57BL/6 mice (C57) were used. Each group consisted of 3 mice. For each mouse, systolic blood pressure, heart to body weight ratio, renal glomerular sclerosis index and angiotensin II concentration in the heart and kidney were measured. Systolic blood pressure of THM was about 40 mmHg higher than that of C57. Heart to body weight ratio and renal glomerular sclerosis index were significantly higher in THM than those in C57. The angiotensin II concentration in THM was about 4 times higher in the heart and about 5 times higher in the kidney compared with that in C57. These results suggest that accelerated tissue angiotensin II production, significant cardiac hypertrophy and renal glomerular sclerosis all occur because of hypertension.