Objective: To design an extravascular trestle model coated phosphorus-32, an isotope radiating beta rays, and investigate its effects on intimal hyperplasia of autologous vein grafts. Methods: ETA cDNA was used as a gene probe specific to vascular SMCs on the basis of in situ hybridization. The femoral veins were transplanted reversely into colateral femoral arteries in rabbits, and the animals were divided into control, chemical agents and phosphorus-32 groups. The morphometry was applied to calculate the ETA cDNA expression and intimal thickness. Spearman correlation method was utilized to investigate their relationship. Results: Intimal thickness in grafts of phosphorus-32 group was markedly reduced. Additionally, intimal ETA gene expression was also decreased in beta rays group. The values increased at a slower rate significantly different from that of control and aspirin groups (P