Watson Linley E, Jewell Coty, Song Juhee, Dostal David E
Central Texas Veterans Health Care System, Temple, TX, USA.
Front Biosci (Elite Ed). 2013 Jun 1;5(3):922-7. doi: 10.2741/e671.
The effects of aldosterone receptor blockade on echocardiography in spontaneously hypertensive rats (SHR) are not fully characterized. In this study, multiple echocardiographic parameters were compared for 42 weeks between SHR versus Wistar-Kyoto rats (WKY) serving as normotensive controls. In addition, echocardiographic parameters were compared for 28 weeks between the SHR versus SHR treated with eplerenone 100 mg/kg/day or spironolactone 50 mg/kg/day. Compared to normotensive WKY rats, SHRs had significantly increased systolic blood pressure, increased cardiac mass, increased isovolumic relaxation time (IVRT), decreased E/A ratio, increased mitral closure opening time interval (MCO) and increased Tei index. Both eplerenone and spironolactone significantly decreased systolic blood pressure compared to the SHR controls. The spironolactone treatment group demonstrated significant increases in heart rate and cardiac output and a decrease in cardiac index compared to SHR controls. Any aldosterone blockade in SHR protected against the increased cardiac mass. Similar to clinical echocardiographic observations, hypertension in rats results in left ventricular hypertrophy (LVH) and diastolic dysfunction and aldosterone receptor blockade reduces LVH in SHR.
醛固酮受体阻断对自发性高血压大鼠（SHR）超声心动图的影响尚未完全明确。在本研究中，对SHR与作为正常血压对照的Wistar-Kyoto大鼠（WKY）进行了42周的多项超声心动图参数比较。此外，还对SHR与接受依普利酮100 mg/kg/天或螺内酯50 mg/kg/天治疗的SHR进行了28周的超声心动图参数比较。与正常血压的WKY大鼠相比，SHR的收缩压显著升高，心脏质量增加，等容舒张时间（IVRT）延长，E/A比值降低，二尖瓣关闭开放时间间隔（MCO）延长，Tei指数升高。与SHR对照组相比，依普利酮和螺内酯均显著降低了收缩压。与SHR对照组相比，螺内酯治疗组的心率和心输出量显著增加，心脏指数降低。SHR中的任何醛固酮阻断均可防止心脏质量增加。与临床超声心动图观察结果相似，大鼠高血压会导致左心室肥厚（LVH）和舒张功能障碍，而醛固酮受体阻断可减轻SHR中的LVH。
