Role of renin-angiotensin system in development of heart failure induced by myocardial infarction in rats.
We investigated the morphologic and functional changes of infarcted rat hearts under a paradigm of angiotensinconverting enzyme inhibition. Myocardial infarction was induced by left coronary artery ligation and a control group (SHAM) underwent sham-operation. Infarcted rats received normal drinking water with (CAP group) or without (INF group) captopril. Functional assessment was performed by electro (ECG) and echocardiogram (ECHO) just before and 21 days after surgery. The ECG of INF and CAP showed similar values and resembled healed infarct after surgery. The most outstanding differences between INF and CAP were the prevention of the increase of P-wave and attenuation both in rightward deviation of the QRS axis and Q-wave amplitude in CAP compared with INF. The ECHO showed that captopril treatment improved the diastolic filling more than systolic performance. Cardiac dilatation and left congestive heart failure were observed only in INF. Both infarcted groups showed a scar tissue in the left ventricular wall, but the INF showed a higher scar area than CAP (49.7+/-5.24 vs. 22.33+/-6.19 respectively). These data suggest that the renin-angiotensin system induces morphologic and functional changes in post-infarcted rat hearts and which can be assessed by non-invasive exams.
Trindade
Daniel C
DC
Universidade de Barra Mansa, Barra Mansa, RJ, 27330-550, Brazil.
Trindade
Raquel C
RC
Marassi
Michelle P
MP
Martins
Ornélia P P R
OP
Costa-e-Sousa
Ricardo H
RH
Mattos
Elisabete C
EC
Marinho
Alcides
A
Reis
Luís C
LC
Olivares
Emerson L
EL
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D000818:Animals; D002216:Captopril / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004452:Echocardiography; D004562:Electrocardiography; D006333:Heart Failure / Q000209:etiology / Q000517:prevention & control*; D009203:Myocardial Infarction / Q000150:complications / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012084:Renin-Angiotensin System / Q000187:drug effects / Q000502:physiology; D016277:Ventricular Function, Left
D000806:Angiotensin-Converting Enzyme Inhibitors; D002216:Captopril