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Objectives To investigate the effects of nicotine on angiogenesis and restenosis in a rabbit model of critical limb ischemia and balloon catheter denuding injury iliac artery. Methods Forty male New Zealand White rabbits were randomly divided into control, low-, middle-, and high-dose (0.005,0.05 or 5 μg/kg, respectively) nicotine groups.Balloon catheter denuding injury iliac artery and ligation of a femoral artery were performed in all animals fed with a high-cholesterol diet (HCD)beginning 2 weeks before operation. Nicotine was administered daily by intramuscular injection in the ischemic hindlimb for 3 weeks. Control rabbits received an equal volume of phosphate-buffered saline alone.Collateral vessels of the ischemic hindlimb were observed by angiography of abdominal aorta, and the density of intramuscular microvessels in ischemic hindlimb was examined by immunohistochemistry. The levels of blood lipids and the indexes of hepatic or renal functions were also determined before HCD and after nicotine treatment. Results One rabbit in control, two in low-, one in middle- and two in high-dose group died during the experiment. The remaining 34 rabbits were included in the study. Two or five weeks after HCD, the levels of blood lipids were significantly increased in all groups, but there was no significant difference on the levels between control and nicotine-treated groups three weeks after nicotine treatment; The indexes of hepatic or renal functions were no significant changes three weeks after nicotine treatment; There were no significant differences on collateral vessels shown by angiography in all four groups; The density of intramuscular microvessels in three nicotine-treated groups was significantly higher than that in control group; But the intimal area in all three nicotine-treated groups was also larger than that in control group.Conclusions The present study shows that intramuscular administration of nicotine for three weeks could not increase arteriogenesis in ischemic hindlimb of rabbits, but is capable of significantly promoting intramuscular angiogenesis in ischemic hindlimb.Nicotine can also accelerate intimal thickening of balloon catheter denuding injury iliac artery, so it may contribute to the development of restenosis.