The inhibition of canine vein graft intimal thickening using a newly developed antiplatelet agent.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of a newly developed antiplatelet agent, 4-cyano-5, 5-bis[methoxyphenyl]-4-pentenoic acid (E5510) on intimal hyperplasia of experimental autologous vein grafts in a distal poor runoff canine model. METHOD: The femoral vein was implanted into the femoral artery preparing a distal poor runoff model. These animals were divided into three groups consisting of the E5510 group, the Aspirin group, and the Control group. The vein grafts were harvested at either 1 or 4 weeks after implantation. RESULTS: At 4 weeks, the degree of intimal hyperplasia of the graft of E5510 group was significantly less than that of the Aspirin group and the Control group (p < 0.05). No significant difference was observed between the Aspirin group and the Control group. At 1 week, the degree of intimal cell proliferation was determined by bromodeoxyuridine (BrdU) incorporation and was expressed as the BrdU labeling index. The BrdU labeling index of the E5510 group was also significantly lower than that of the Control group (p < 0.05). CONCLUSIONS: These data demonstrate the efficacy of E5510 in reducing intimal hyperplasia of vein grafts under distal poor runoff conditions by reducing the degree of smooth muscle cell proliferation.