[Comparative effects of carvedilol, losartan and their combination in preventing left ventricular remodeling after acute myocardial infarction in rats].
OBJECTIVE
To compare the effects of carvedilol, losartan and their combination in preventing from left ventricular remodeling (LVRM) after acute myocardial infarction(AMI) in rats.


METHODS
Twenty-four hours after ligating left coronary artery, 100 surviving AMI female SD rats were randomly assigned to: (1) AMI control (n = 25), (2) carvedilol (1 mg x kg(-1) x d(-1)) (C1) (n = 25); (3) losartan (3 mg x kg(-1) x d(-1)) (L3)(n = 25); and (4) carvedilol (1 mg x kg(-1) x d(-1)) + losartan (3 mg x kg(-1) x d(-1)) (C1 + L3) (n = 25) groups. Sham-operated group (n = 17) were selected randomly as non-infarction control. After 4 weeks of therapy with the drugs by gastric gavage, hemodynamic studies were performed, then the rat hearts were fixed and pathologically analyzed. Exclusive of the rats with MI size < 35% or > 55%, complete data were obtained in 65 rats, which were comprised of AMI control (n = 13), C1 (n = 12), L3 (n = 13), C1 + L3 (n = 14) and sham-operated (n = 13) groups.


RESULTS
There were no significant differences in MI size among the four AMI groups (45.8% - 46.7%, P > 0.05) . Compared with sham-operated group, Left ventricular (LV) end diastolic pressure (LVEDP), volume (LVV), weight (LVW), septal thickness (STh) and right ventricular weight (RVW) were all significantly increased (all P < 0.01 ) in AMI group, while the left ventricular pressure maximal rate of rise and fall (dp/dt) were significantly decreased (all P < 0.01). In comparison with AMI group, LVEDP, LVV, LVW, STh and RVW were all significantly decreased (all P < 0.01), while +/- dp/dt and +/- dp/dt/LVSP were significantly increased (P < 0.05 - 0.01) in all three therapy groups, with LVEDP decreasing more in the combination and L3 groups than in C1 group (P < 0.05 - 0.01) and STh decreasing more in the combination group than in C1 group (P < 0.01), but there were no significant differences in other variables among the three therapy groups.


CONCLUSIONS
Carvedilol, losartan and their combination all can prevent from LVRM after AMI in rats, improve hemodynamics and LV function, with the combination superior.
Yang
Y
Y
Cardiovascular Institute, Fuwai Heart Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing 100037, China.
Tang
Y
Y
Ruan
Y
Y
Li
Y
Y
Gao
R
R
Chen
Z
Z
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D047228:Angiotensin II Type 1 Receptor Blockers / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D002227:Carbazoles / Q000008:administration & dosage / Q000494:pharmacology*; D000077261:Carvedilol; D004359:Drug Therapy, Combination; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D019808:Losartan / Q000008:administration & dosage / Q000494:pharmacology*; D009203:Myocardial Infarction / Q000188:drug therapy / Q000503:physiopathology*; D011412:Propanolamines / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016277:Ventricular Function, Left / Q000187:drug effects; D020257:Ventricular Remodeling / Q000187:drug effects*
D000319:Adrenergic beta-Antagonists; D047228:Angiotensin II Type 1 Receptor Blockers; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol; D019808:Losartan