ARYA Atherosclerosis2420101208THE EFFECT OF ASPIRIN ON SERUM VASCULAR ENDOTHELIAL GROWTH FACTOR AND NITRIC OXIDE CONCENTRATION IN HIGH-CHOLESTEROL FED RABBITS164164ENMajidKhazaeiM.D. Ph.D., Assistant Professor, Physiology Dept., School of Medicine, Isfahan University of Medical Sciences, Isfahan.. majkhazaei@yahoo.comMehdiNematbakhshHosseinAhmadiMohsenMasjedi20101208  Abstract INTRODUCTION: Hypercholesterolemia is one of the major risk factors for atherosclerosis which is characterized by endothelial dysfunction. This study was designed to investigate the effect of aspirin on serum vascular endothelial growth factor (VEGF) and nitric oxide (NO) concentrations in hypercholesterolemic animals. methods: Sixteen male rabbits were randomly divided into two groups, aspirin-treated and control. Aspirin (10 mg/kg/day) was administered orally using feeding tube. All animals were fed with high-cholesterol diet (1%) during the experiment. After five weeks, blood pressure, serum lipid and lipoprotein profiles, serum VEGF and NO concentrations were measured. results: Aspirin did not change blood pressure. Aspirin significantly decreased serum LDL (1276±72.1 vs. 1505±68.03 mg/dl) and triglyceride (477.5±8.3 vs. 649.1±15.2 mg/dl) (P<0.05). High-cholesterol diet significantly decreased serum VEGF level in both groups (control: 24.59±0.42 vs. 38.09±2.49 pg/ml; aspirin: 24.72±0.84 vs. 42.29±2.03 pg/ml) (P<0.05) and aspirin did not change serum VEGF level in hypercholesterolemic animals (P>0.05). Serum NO concentration was also significantly decreased after five weeks of high-cholesterol diet (control: 5.87±0.33 vs. 8.67±0.68 μmol/lit; aspirin: 5.66±0.33 vs. 8.58±0.60 μmol/lit) (P<0.05). Aspirin did not change serum NO level (P>0.05). CONCLUSIONS: We conclude that under the conditions of this study, aspirin cannot change serum VEGF and NO concentrations in high-cholesterol fed animals.     Keywords: Hypercholesterolemia, nitric oxide, vascular endothelial growth factor, aspirin.