口服小剂量螺内酯抗高血压大鼠心肌纤维化

目的观察口服小剂量螺内酯对自发性高血压大鼠(SHR)血压、心肌间质和血管周围胶原沉积的干预,探讨螺内酯在高血压心肌纤维化进展期对心脏的保护作用。方法20只雄性SHR随机分为螺内酯组(10只)和安慰剂组(10只),另设Wistar-kyoto鼠7只(WKY组)。Western blot方法分析Ⅰ型胶原的表达;天狼猩红-苦味酸染色观察心肌胶原容积分数(CVF)和血管周围胶原面积(PVCA)。结果与安慰剂组比较,螺内酯组Ⅰ型胶原含量、CVF、PVCA显著降低(P<0.01),收缩压、舒张压、平均动脉血压、血K+、心脏重量指数、左心室重量指数、心率未见明显差异。结论口服小剂量螺内酯通过减少Ⅰ型胶原的沉积,起到抗高血压大鼠心肌纤维化的作用。

The experimental study of prevention of myocardial fibrosis by low-dose oral spironolactone in spontaneous hypertension rats

Objective To investigate the beneficial effects of low-dose oral spironolactone on heart during the progressing stage of hytertension.Methods Twenty eight-week-old male spontaneous hypertension rats(SHR) were divided randomly into spironolactone group(SHR-SPIRO,n=10) and control group(SHR-CON,n=10),sex-age matched Wistar Kyoto rats(WKY group,n=7) were also used as another group.Collagen type-Ⅰ expression was analysed by Western blot.Myocardial paraffin section was stained with sirius red to determine collagen volume fraction(CVF) and perivascular collagen area(PVCA) by quantitative morphometry.Results Compared with SHR-CON group,collagen type-Ⅰ,CVF and PVCA were significantly reduced in SHR-SPIRO group(P<0.01),while systolic blood pressure,diastolic blood presure,mean arterial blood pressure,heart weight index,left venticular weight index and plasma K+ concentration had no differences.Conclusion Low-dose oral spironolactone prevent myocardial fibrosis probably by decreasing the content of collagen type-Ⅰin the left ventricle.