Aim To evaluate the effectiveness of nifedipine and enalaprilat on collagen proliferation after balloon injury in a rabbit model. Methods Thirty-two healthy male New Zealand white rabbits were divided into control group, nifedipine group and enalaprilat group. Conventional balloon angioplasty in the right common iliac artery was done. Arterial bloods were taken before angioplasty, 30 minuets and 2 weeks after angioplasty for analyzing plasma AngⅡ. For histology, Masson's staining was performed two weeks later. All the specimens were analyzed using a computerized imaging analysis system. Results In the control group, plasma AngⅡ elevated from 2.70±0.31 g/L to 2.83±0.18 g/L 30 min after angioplasty (P<0.05), and returned to 2.50±0.26 g/L two weeks later (P<0.05). There was no significant AngⅡdifferences between the control and the nifedipine groups. Enalaprilat significantly inhibited plasma AngⅡ elevation 30 min after angioplasty. Histological computerized imaging analysis showed significant collagen proliferation after angioplasty (P<0.01). There was a significant decrease of collagen proliferation in the enalaprilat group (P<0.01). Conclusions Significant vascular wall collagen proliferation was observed after angioplasty. Enalaprilat inhibited vascular wall collagen proliferation, thus may be effective in the prevention of resrenosis after successful pecutaneous transluminal coronary angioplasty.