[Effects of pravastatin, fosinopril and their combination on myocardium TNF-alpha expression and ventricular remodeling after myocardial infarction in rats].

OBJECTIVE

To investigate the effects of pravastatin, fosinopril and their combination on ventricular remodeling, cardiac function, tumor necrosis factor-alpha (TNF-alpha) mRNA expression, and matrix metalloproteinases (MMPs) activities after myocardial infarction (MI) in rats.

METHODS

Acute myocardial infarction (AMI) was established by ligation of the anterior descending coronary artery in male Sprague-Dawly (SD) rats. Twenty-four hours after the procedure, the 48 surviving rats were grouped randomly as AMI control, fosinopril (10 mg.kg(-1).d(-1)), pravastatin (20 mg.kg(-1).d(-1)) and a combined use of the 2 drugs. Sham-operated group (n = 8) was taken randomly as non-infarction control. Six weeks after treatment with the drugs by gastric gavage, heart function and left ventricular remodeling were assessed. Left ventricular weight (LVW)/body weight (BW) ratio was determined. The relative expression of myocardium TNF-alpha mRNA was assessed by reverse transcription-polymerase chain reaction. Left ventricular myocardium MMPs activities were assessed by Zymography.

RESULTS

There were no significant differences among the four AMI groups in infarction size (P > 0.05). In comparison with the AMI group, left ventricular end-diastolic pressure, left ventricular end-diastolic diameter, LVW/BW all decreased significantly (P < 0.05 - 0.01); while dp/dtmax, dp/dtmin, fractional shortening (FS) and ejection fraction (EF) increased significantly in all three drug-treated groups (P < 0.05 - 0.01); increments of FS, LVEF and dp/dtmax were more evident in the combination group than either the fosinopril or pravastatin group (P < 0.05). The levels of TNF-alpha mRNA in AMI rats treated with fosinopril, pravastatin and their combination reduced 29%, 26% and 33%, respectively (P < 0.01); MMP-2 activity reduced 25%, 30% and 35%, respectively (P < 0.01); MMP-9 activity reduced 20%, 18% and 24%, respectively (P < 0.01). There were no significant differences in other variables among the 3 treatment groups (P > 0.05).

CONCLUSION

Pravastatin, fosinopril and their combination showed favorable effects on left ventricular remodeling after AMI in rats and demonstrated improved cardiac function. The combined treatment group yielded better results in the context of improving left ventricular systolic function. These effects could be relevant to the attenuation of increased MMP-2 and MMP-9 activities and left ventricular expression of TNF-alpha.