自发性高血压大鼠左室不同部位心肌纤维化程度的改变:病理变化与心肌密度改变的对比观察

Observation of dynamic changes of myocardial fibrosis and correlated cardiac texture:alterations in different areas of SHRs' left ventricle

目的 探讨自发性高血压大鼠 (SHR)左室室间隔、前壁、后壁及侧壁心肌纤维化的动态变化 ,以及心脏超声显像结合计算机分析检测心肌密度这一方法的可靠性。方法 应用病理及生化检查 ,检测SHR左室室间隔、前壁、后壁及侧壁心肌纤维化的病变程度 ;通过心脏超声显像并结合计算机分析 ,检测大鼠的心肌密度的变化。结果 14周时 ,代表心肌纤维化水平的参数羟脯氨酸浓度 (HC)在SHR室间隔、前壁及后壁即已增高 ,以室间隔最为明显 ,而左室侧壁虽有增高趋势 ,但未达到显著性水平 ;2 4周时各部位均明显增加 ,但各部位之间的差异明显减少。在 14周时 ,代表血管周围纤维化水平的参数血管周围胶原面积 (PVCA)在左室各部位较对照组均显著增高 ,2 4周时增高更为明显 ,但各部位之间无显著性差异。而代表间质纤维化水平的参数胶原容积分数 (CVF)在 14周时只有室间隔显著增高 ,其余各部位无明显变化 ;2 4周时各部位均有显著增高 ,但仍以室间隔增高最为明显。心肌灰度均值在 14周时各部位均较对照组显著增高 ,各部位之间比较 ,室间隔最高 ,侧壁最低 ,二者之间有显著性差别。 2 4周时各部位均较 14周显著增高 ,但各部位之间差别变小。在室间隔 ,灰度离散度在 14及 2 4周均未出现显著性改变 ,而其他部位则在 14周时增高 ,2

Objective To research the dynamic changes of myocardial fibrosis in different areas of spontaneously hypertensive rats' (SHRs') left ventricle and the reliability of the method examining cardiac texture with echocardiography and computed processing.Methods The parameters representing myocardial fibrosis(MF)of SHR and control WKY were exanined with histomorphological observations and biochemical assays.The cardiac texture was measured with echocardiography and computed processing.Results Hydroxylproline Concentration(HC),which represents MF elevated markedly in the interventricular septum(IVS),anterior wall and posterior wall at 14th week,and increased most significantly in the IVS;while in the lateral wall,although the HC had some tendency of elevation,no significant changes happened.At 24th week,the HC in all areas increased markedly,but no great difference among various areas.The perivascular collagen area(PVCA),representing perivascular fibrosis,raised significantly at 14th week,and more markedly at 24th week,but no difference among various parts.The collagen volume fraction(CVF),representing interstitial fibrosis,raised in the IVS at 14th week,and in all areas at 24th week,but still most significantly in the IVS.The mean value of cardiac texture raised in all parts at 14th week,but highest in IVS,lowest in lateral wall (compared between them,P<0.05);at 24th week,it was higher than 14th week ,but the difference among various areas became less.The standard deviation of the cardiac texture had no changes in the IVS at 14th and 24th week,while in the other parts,it increased at 14th week and became normal in the 24th week.Conclusion In the process of hypertension,myocardial fibrosis,especially interstitial fibrosis develops in a heterogeneous manner at various areas of left ventricle ,severe in IVS,mild in lateral wall.The method of echocardiography with the computed processing,by means of measuring the cardiac texture,may examine the degree of MF objectively.