芦沙坦和西拉普利对大鼠心肌梗死后心肌间质胶原重构的影响

目的　研究芦沙坦和西拉普利对心肌梗死 (MI)后梗死区 (IZ)和非梗死区 (NIZ)胶原沉积的影响。方法　大鼠MI后第 2天用芦沙坦 ,或西拉普利治疗 6周或不治疗 ,并设假手术组。结果　与假手术组比 ,MI组左心室最大上升速率 (+P’max)和下降速率 (-P’max)明显降低 ,而左心室舒张末压 (LVEDP)、血浆Ⅲ型前胶原氨基末端肽 (PⅢNP)和Ⅰ型前胶原羧基末端肽 (PⅠCP)、IZ和NIZ胶原含量和胶原Ⅰ Ⅲ比值均明显增加。与MI组比 ,芦沙坦和西拉普利治疗组 +P’max和 -P’max增加 ,PⅢNP和PⅠCP含量下降。西拉普利使NIZ胶原含量和胶原Ⅰ Ⅲ比值明显降低并轻度降低IZ胶原含量。芦沙坦对胶原含量无明显影响。结论　在大鼠MI后早期应用西拉普利和芦沙坦治疗都能改善血流动力学 ,但抑制心肌纤维化的作用芦沙坦不如西拉普利明显

Effect of losartan and cilazapril on remodeling of myocardial interstitial collagen after myocardial infarction in rats

Objectives To investigate the effect of losartan and cilazapril on deposition of collagen in infarct zone (IZ) and non-infarct zone (NIZ) in myocardial infarction rats.Methods A rat model of acute myocardial infarction was established by ligation of left coronary artery.The rats were randomised to from treatment with losartan (15 mg/kg·d -1 ),or cilazapril (5 mg/kg·d -1 ) beginning the second day after operation for 42 days or without the treatment,and sham operated rats were used as the control group.Results Compared with the sham operation group,the myocardial infarction rats showed significant decrease in arterial pressure,maximal ascending velocity (+P'max) and maximal descending velocity of the left ventricular pressure (-P'max) and significant increase in left ventricular end diastolic pressure (LVEDP), procollagen type Ⅰ carboxyl-terminal peptide (PⅠCP) and procollagen type Ⅲ amino-terminal peptide(PⅢNP) in plasma,collagen contents and collagen type Ⅰ/type Ⅲ ratio in IZ and NIZ.Compared with infarction group without the treatment,groups treated with losartan or cilazapril had higher +P'max and -P'max,lower levels of plasma PⅠCP and PⅢNP.Cilazapril decreased significantly the content of collagen in NIZ and collagen type Ⅰ/type Ⅲ ratio,decreased slightly the collagen content in IZ.Losartan did not significantly decrease the contents of collagen both in IZ and NIZ.Conclusion Early treatment with losartan or cilazapril could improve the left ventricular function.The effect of cilazapril on fibrosis in IZ and NIZ was more significant than that of losartan.