採用腹動脈完全結紮大白鼠模型來探討血管昇壓素-II 轉換酵素抑制劑(captopril),對心肌肥大之阻斷作用。此研究主要針對手術初期,即腹動脈結紮手術後7天內之大白鼠,為研究對象。發現動脈結紮後7天之大白鼠,體重減少28%,而頸動脈壓在結紮後1天即上升,收縮壓於第一天即由正常之143mmHg上升至175mmHg,在第七天上升至201mmHg,並持續不降。而心肌則在結紮後1-2天顯著肥大,且位結紮點上方之右腎,由第一天起亦持續的肥大,唯紮點下方之左腎,因血液補充之缺乏,在結紮後第二天則持續的萎縮。然而,當在結紮大白鼠飲水中添加血管昇壓素-II轉換酵素的抑制劑(captopril) 時,則完全阻斷血壓上升,心肌及右腎肥大之現象,唯一僅造成全心重比正常大白鼠稍減低的副作用。在此,我們首度發現血管昇壓素-II 轉換酵素抑制劑,可徹底阻斷腹動脈完全結紮大白鼠所誘發之心肌肥大現象。
Captopril is an angiotensin II-Converting enzyme inhibitor. We examined its inhibitory effect on cardiac hypertrophy for seven days following complete surgical coarctation of the rat abdominal aorta between origins of the renal arteries. Body weights of coarcted rats (CR) decreased to 28% less than shams by day 7. Throughout the study, carotid arterial systolic blood pressure(BP) remained at about 143 mm Hg in shams. In CR, it increased rapidly within 1 day, rose to 201 mm Hg bye day 3 and thereafter remained constant. Heart of CR rapidly and significantly enlarged over shams by 1 to 2 days. Weights of pressure-loaded right kidneys in CR significantly increased throughout the 7 days, while weights of the pressure-protected left kidneys significantly decreased from day 2 onward. Captopril totally reversed high BP and ventricular and right kidney hypertrophy in CR to the extent that they were the same as in shams, except for slightly reduced heart weight. For the first time, we have demonstrated that Captopril fully inhibited cardiac hypertrophy and high BP in an in vivo system induced by complete surgical coarctation of the abdominal aorta in rats.