Inhibitory effect of adenosine on intimal hyperplasia and proliferation of smooth muscle cells in a carotid arterial anastomosis animal model

Purpose: The effect of adenosine (9-beta-0-ribifuranosyladenine) on the endothelial cell proliferation and neointimal hyperplasia is investigated in the rabbit carotid artery anastomosis model. Methods: Twenty-eight New Zealand white rabbits were arranged in four groups of seven animals each. The right carotid arteries of each animal were transsected and re-anastomosed. The left sides remained as control. In Group A, no medication was used. In Group B, subcutaneous Adenosine was applied for 3 days. In Group C, the same dose was applied for 7 days, and in Group D for 21 days. After 28 days, the luminal diameters, luminal areas, intima/media ratios were all measured by using histopathological evaluation. Findings: The mean luminal diameters and areas of the four groups were smaller than the control ones. Massive thickening of smooth muscle cell proliferation and dense intensifying in the connecting tissues were observed most prominently in Group A, in decreasing degrees within other groups. Intima/media ratio was highest in Group A. Scoring the quantity of e-NOS positive staining also revealed a significant difference between the experimental groups and their control associates. Conclusion: The process of endothelial cell proliferation and neointimal hyperplasia can be significantly reduced by the use of adenosine.