Objective: To observe the urokinase receptor (uPAR) expression in atherosclerotic plaques of human femoral arteries.
Methods: Human femoral artery samples were collected from patients underwent femoral endarterectomy. Normal internal mammary artery samples were taken from bypass surgery served as control. uPAR protein distribution at shoulders, lipid pool and rupture sites of a plaque and the association with macrophages and smooth muscle cells (SMCs) were detected by immunohistochemistry methods.
Results: There was no uPAR expression in intima or tunica media of normal internal mammary arteries. In atherosclerotic lesions of femoral artery, the mean optical density (A) of uPAR was 92 +/- 37 in intima and 46 +/- 28 in tunica media (P < 0.05). The intimal uPAR was coexisted with macrophages and SMCs. uPAR expression was observed at plaque shoulders and lipid pool, while the maximal expression was found at rupture sites.
Conclusion: The increased expression of uPAR in atherosclerotic lesion and uPAR distribution at shoulders, lipid pool, as well as rupture sites of plaques suggest a role of uPAR in plaque rupture process.