The effects of nebivolol on intimal hyperplasia after vascular injury

Intimal hyperplasia plays role in the physiopathology of atherosclerosis and occurs as a response to trauma after invasive vascular procedures. It is a clinical problem which forms in vascular wall as a result of smooth muscle celi migration, proliferation and extracellular matrix accumulation. Nitric oxide that is secreted from endothelium plays an important role for preventing vascular intimal hyperplasia. At this study; we examined the effects of nebivolol which is third generation beta blocker and augments vascular nitric oxide, on intimal hyperplasia at denadue endothelial tissue. At the study 21 New Zelland male white rabbit were used. They were divided into 3 groups which includes 7 rabbits at each one. The rabbits in group I (Control group) only underwent balloon injury on abdominal aorta. The rabbits in group 2 (solvent group) were treated with solvent solution and the rabbits in group 3 (nebivolol group) were treated with nehivoiol [2.5 mg/kg/day) intraperitoneally two days before injury and were continued for 28 days. At the end of the study, the rabbits were killed and abdominal aortas were harvested. Upon them: intimal. medial areas were measured and intima/media ratios were calculated. For endothelin-I. hFGF and PDGF-p: sections were detected as immimohistologically. And tissue nitric oxide levels were measured by Griess reaction. Statistically there were no differences between control and solvent groups at intimal areas, medial areas, intima/media ratios, immunstaining and tissue NO levels (p>0.05). The neointimal thickening was significantly less in nehivoiol group than in control and solvent group (p<0.001). There were no differences at medial areas (p>0.05). Intima/media ratio was decreased in nebivolol group (p