榅桲总黄酮对自发性高血压大鼠心脏结构和功能的影响

Effects of total flavonoids from Cydonia oblonga on cardiac structure and function in spontaneously hypertensive rats

目的研究榅桲Cydonia oblanga Mill.总黄酮对自发性高血压大鼠(SHR)心脏结构和功能的影响。方法大鼠分为模型组(SHR组)、卡托普利组[25 mg/(kg·d)]、杜仲平压片组[30 mg/(kg·d)]和榅桲总黄酮低、中、高剂量组[40、80、160 mg/(kg·d)]剂量组。WKY大鼠给予蒸馏水,作为正常对照组。灌胃给药16周后,进行超声心动图、心脏血流动力学和组织病理学检查,评价榅桲总黄酮对大鼠心脏结构和功能的影响。Masson染色后,光镜下观察心肌纤维化程度。结果超声心动图结果显示,与SHR组比较,榅桲总黄酮组左心室舒张末期内径、左心室收缩末期内径、室间隔厚度指数均有所降低,左心室质量、左心室质量指数、左心室质量/体质量比均明显减小,榅桲总黄酮中、高剂量组左心室内径缩短率、左心室射血分数增大,其中榅桲总黄酮高剂量组变化最大。血流动力学测定结果显示,与SHR组比较,榅桲总黄酮组收缩压、舒张压、左室收缩压、左室舒张末期压降低,室内压最大上升速率、室内压最大下降速率减小,收缩时间无明显变化,舒张时间延长,心率减小但无显著性差异。Masson染色结果显示,榅桲总黄酮高剂量组心肌纤维化明显减少。结论榅桲总黄酮可改善自发性高血压大鼠心脏功能,抑制心肌肥厚,并减轻心肌纤维化。

AIM To study the effects of total flavonoids from Cydonia oblonga Mill.（ COMF） on the cardiac structure and function in spontaneously hypertensive rats（ SHR）. METHODS The rats were divided into model group（ SHR group）,captopril group [25 mg /（ kg·d） ],Duzhong Pingya Tables group [30 mg /（ kg·d） ],low,middle and high doses of COMF [COMF-L,COMF-M and COMF-H,40,80 and 160 mg /（ kg·d） ]groups. WistarKyoto（ WKY） rats were given distilled water as control group. After sixteen weeks of intragastric administration,the echocardiography,hemodynamics and histopathological examinations of heart were performed to investigate the impacts of COMF on cardiac structure and function of rats. The myocardial fibrosis degree was observed at light microscope after Masson staining. RESULTS The echocardiography results showed that,as compared with SHR group,the indexes of left ventricle internal dimension in end-diastole and end-systole,and interventricular septal thicknesswere decreased in COMF groups; left ventricle mass and its index,and ratio of left ventricle mass to body weight were significantly decreased in COMF groups; left ventricle internal dimension’ s shortening rate and ejection fraction were increased in COMF-M and COMF-H groups,and the variation was the most abundant in COMF-H group. The hemodynamics results showed that,as compared with SHR group,COMF groups showed systolic and diastolic blood pressure,left ventricular systolic and end-diastolic pressure lowered; maximum rates of rise and fall in intraventricular pressure were decreased; systolic duration showed no obvious changes; diastolic duration was prolonged; heart rate was decreased but without any significant difference. The Masson staining results showed that myocardial fibrosis was significatly decreased in COMF-H group. CONCLUSION Total flavonoids from C. oblonga can improve the cardiac function,inhibit the cardiac hypertrophy,and alleviate the myocardial fibrosis in SHR.