Abstract: Aim To study the effect of Irbesartan on neointimal proliferation in vivo after vascular injury.Methods Iliac arteries of Wistar rats were injured with a 2 French balloon catheter.Irbesartan (30mg/kg.d or 10mg/kg.d)or vehicle was given by gavage from 1 day before to 14 days after balloon injury.Morphometrical changes in the injury iliac artery were analyzed.Results Irbesartan significantly inhibited the increase of cell count in injured vessel wall, intimal thickening and vascular smooth muscle cells proliferation in a dosage-dependent relationship.The cellular density of the neointima was not affected by Irbesartan.Conclusion The results indicate that Irbesartan may reduce neointima formation after blloon injury and therefore it may be capable of preventing testenotic lesions after angioplasty in humans.

Key words: irbesartan, endothelium