Investigation on the effect of 4-hydroxy-2,2,6,6,-tetramethylpiperidine-1-oxyl (tempol) on survival of vein grafts in rats

Intimal hyperplasia is among the major causes of restenosis that occurs aftermicrosurgical interventions. In this study, we aimed at investigating the effects of Tempol,which has a superoxide dismutse-mimetic action, on preventing intimal hyperplasia onfemoral vein grafts in rats.20 Wistar species Albino rats were seperated into two groups, as ten rats in each group. A2 cm-long defect was created on the femoral artery and then repaired with ipsilateral femoralvein graft. During the postoperative 25 days, intraperitoneal Tempol was applied to the studygroup, whereas isotonic sodium chloride was applied to the control group. At the end of thisperiod, blood samples and vein specimens were obtained. The specimens were then stainedwith HE and Verhoeff?s elastic stain. Biochemically, the serum was analysed for TotalAntioxidant Capacity, Total Oxidation Level, and Proxanase-1 level. The data were analysedwith nonparametric Mann-Whitney U Test of SPSS 14.0 statistical program.During the postoperative follow-up period, one rat in the study group and three in thecontrol group were excluded from the study due to wound dehiscence and trombosis .Binary comparison with Mann-Whitney-U test revealed a statistically significant differencefor intimal and medial thicknesses (p<0.01), whereas comparison of intima/media ratios wereinsignificant (p<0.00). A statistically significant difference for TAS, TOS, OSI and POS-1levels was also obtained (p<0.01).In this study, we found that Tempol prevents formation of reactive oxygen species anddevelopment of intimal hyperplasia in the vein grafts, thus increasing the antioxidant capacity.Key words: SOD mimetic Tempol, İntimal hyperplasia, Vein graft, Reactive oxygen species.