The role of cardiac renin-angiotensin system in the development of volume-overload myocardial hypertrophy in rats / 中国病理生理杂志

ABSTRACT

The present study was performed to determine whether or not that cardiacrenin-angiotensin system (RAS) plays an important role in volume-overload myocardialhypertrophy. In order to control the increase of circulating RAS, aortacava fistula withnephrectomy (ACF+NT) rats were used in the experiment. The ventricular angiotensin Ⅰ,Ⅱ (Ang Ⅰ,Ⅱ) contents and angiotensin-converting enzyme (ACE) activities were measuredby means of radioimmunoassay and biochemical method. It was shown that in ACF+NTrats, the Ang Ⅱ contents and ACE activities in both left and right ventricles increasedsignificantly despite the plasma Ang Ⅰ, Ⅱ and renin activity remained at a lower level.These results indicate that (1) Cardiac RAS as a relatively independent system, plays aregulatory role in the development of volume-overload cardiac hypertrophy; (2) The in-crease of Ang Ⅱ content was partly caused by the enhancement of ACE activities; (3) Atleast at the early stage of volume-overload cardiac hypertrophy, the circulating RAS maynot be a necessary promoter.