Intravenous administration of vascular endothelial growth factor improves cardiac performance and inhibits cardiomyocyte apoptosis

This study investigated the effects of vascular endothelial growth factor (VEGF) intravenous administration on cardiac performance and cardiomyocyte apoptosis in a rat model of acute myocardial infarction. Left coronary artery ligation produced extensive myocardial infarction in 48 rats and sham operated in 24 animals. Twenty-four hours after surgery, the rats were randomized to receive VEGF₁₆₅–heparin (treated group) or heparin–saline (control group) treatment. The sham-operated animals were also to receive VEGF₁₆₅–heparin (sham group) treatment. VEGF₁₆₅ (2 μg/ml) with heparin (50 U) or heparin–saline (50 U/ml) was administered daily via the tail vein for 7 and 14 days. Fifty-eight rats survived and included in the study. There were not significant effects of VEGF on hemodynamic parameters in sham animals. As compared with control animals at 9 days after ligation (with 10 rats for each group), rats treated with VEGF had significantly higher maximum rate of left ventricular pressure rise (+dP/dt_max) or fall ( ? dP/dt_max) and microvessel counts, and significantly lower left ventricular end-diastolic pressure (LVEDP) and infarct size. At 16 days after surgery (12, 7 and 9 rats in sham, control and treated groups; respectively), VEGF treatment significantly increased mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), ± dP/dt_max and microvessel counts, and significantly decreased LVEDP and infarct size. VEGF treatment significantly inhibited cardiomyocyte apoptosis and the expression of p53, Fas and Bax protein, and increased the expression of Bcl-2 protein in myocardium at 9 days after myocardial infarction.