PURPOSE: To obtain phVEGF165 for angiogenesis and to compare the effects of its intra-arterial and intramuscular administration in a chronic ischemic rabbit hindimb model. MATERIALS AND METHODS: Chronic ischemic models were constructed in the left hindlimb of rabbits and divided into control (n=6), intra-arterial (n=7) and intramuscular groups (n=5). Plasmid DNA (phVEGF165) expressing vascular endothelial growth factor (VEGF) was obtained from HL60 cells, and transfection into CHO cells and western blot analysis of the medium, as well as proliferation assay of CPAE cells were performed. Two weeks after construction of the models, 500 mug phVEGF165 was injected into both the left common iliac artery and thigh muscles. Angiography was performed and the number of vessels counted, and ELISA was used to determine the quantity of VEGF in blood samples. Wilcoxon signed rank test was employed for statistical analysis. RESULTS: VEGF165 was expressed on western blot of the culture medium. Proliferation assay showed that optical densities were 0.73+/-0.043 in the control study and 1.09+/-0.015 in phVEGF165. The angiographic scores were 1.32+/-0.13 (pre-gene therapy) and 1.30+/-0.07 (post-gene therapy) in the control group, 1.42+/-0.15 and 1.59+/-0.09 in the intra-arterial group, 1.59+/-0.27 and 1.14+/-0.12 in the intramuscular group. The differences were not statistically significant. In the intra-arterial group, serum VEGF levels were 39.96+/-1.08 pg/ml (pregene therapy), 44.99+/-2.13 pg/ml (4th day), 48.18+/-1.49 pg/ml (1st week), 45.70+/-3.77 pg/ml (2nd week), and 46.54+/-5.47 pg/ml (3rd week), but in the control and intramuscular groups there were no increases. CONCLUSION: phVEGF165 affected the proliferation of CPAE cells. There was no difference in angiographic scores and serum VEGF levels between intra-arterial and intramuscular administrations.