The Effect of Short-term Intra-arterial Delivery of Paclitaxel on Neointimal Hyperplasia and the Local Thrombotic Environment after Angioplasty

Abstract

To evaluate the effects of short-term intra-arterial delivery of paclitaxel on neointimal hyperplasia and the local thrombotic environment after angioplasty. An experimental common carotid artery injury model was established in 60 rats, which were divided into experimental groups (40 rats) and controls (20 rats). Local intra-arterial administration of paclitaxel was applied at 2 doses (90 and 180μg/30μl), and the effects of short-term delivery of paclitaxel on neointimal hyperplasia and the expression of tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (t-PA) were evaluated at days 15 and 30 by hematoxylin and eosin staining and immunohistochemistry. At 15 and 30days after injury, neointimal thickness and area, the ratio of intimal area to medial area and the stenotic rate were all significantly decreased in the group provided the high concentrations (180μg/30μl) of paclitaxel for 2min or 10min and in the group provided the low concentration (90μg/30μl) of paclitaxel for 10min (p<0.05). At 30days after injury, there were no significant changes in TF expression among all experimental groups. PAI-1 expression increased in the neointima of the high concentration 10min group (p<0.05), while t-PA expression decreased in the neointima of the high concentration 2min group (p<0.05). In the rat common carotid artery injury model, the short-term delivery of paclitaxel could effectively inhibit neointimal hyperplasia in the long term, with very little influence on the local expression of TF and PAI-1.