Adventitia applied slow-releasing triptolide inhibits intima hyperplasia in vein graft

Objective To investigate the inhibitory effect of appling slow-releasing triptolide on adventitia on the intima hyperplasia of autologous vein graft.Methods In 24 male New Zealand rabbits, external jugular vein to common carotid artery models were established, and then were divided into 3 equal groups at random: blank-control group, receiving no management on adventitia of the vein graft; F-127 control group, receiving local application of 0.5 mL of 20 % F-127 on adventitia of the vein graft; experiment group, receiving local application of 0.5 mL of 20 % F-127 containing triptolide 300μg. Vein graft specimens were harvested at 2 weeks after the operation. Histomorphologic methods were used to detect the degree of intima hyperplasia of the specimens. The expression of bcl-2 and Fas of the specimens was detected by immunohistochemistry. The apoptosis vascular smooth muscle cells (VSMC) were detected by TUNEL.Results Two weeks after vein grafting, compared to blank-control group and F-127 control group, intima hyperplasia of experiment group [intima thickness (29.9±7.6)μm, I/M 0.56±0.08] was markedly inhibited (P0.05). Expression of bcl-2[(18.2±8.4)%] was reduced significantly, however, expression of Fas(21.4±8.9)% increased markedly, and the apoptotic cells [(28.4±7.6)%] also increased markedly (P0.05).Conclusions Applied slow-releasing triptolide by F-127 pluronic on the vein graft adventitia can effectively inhibit intima hyperplasia of vein graft by a mechanism of enhancement of VSMC apoptosis.