The gene expression of nuclear transcriptional factor-κB and IκB in autogenous vein graft in rats

Objective To investigate the gene expression of nuclear transcriptional factor κB(NF κB) p65 and its inhibiting factor I κB in autogenous vein graft. Methods The right common jugular vein was transplanted to infrarenal abodminal aorta by microsurgical technique among 80 Wistar rats so as to establish an autogenous vein graft model. Ten vein graft samples were harvested 6 hours, 24 hours, 3 days, 7 days, 2 weeks, 4 weeks, 6 weeks, and 8 weeks after surgery. NFκB p65 mRNA and IκBβ mRNA were measured by reverse transcription PCR and in situ hybridization. Western blotting and immunohistochemistry were used to detect the protein expression of NFκBp65 and IκB. Results The expressions of NFκB p65 mRNA and IκBβ mRNA 6 hours after the surgery were 16%±4% and 31%±9% respectively ( P 0.01 vs. control vein). The expression of NFκB p65 mRNA reached in peak during the period 3 days to 7 days after the surgery (37%±12% and 34%±10% respectively, P 0.01 vs. other teams), however, the IκBβ mRNA expression reached its peak during 1 to 2 weeks after the surgery (53%±17% and 49%±10% respectively, P 0.01 vs. other teams). The expressions of NFκBp65 mRNA and IκBβ mRNA recovered to their baseline values 6 weeks after surgery. The expression of p65 protein reached its peak 1 week after the surgery (32%±13%) and then decreased gradually. The expressions of IκBα and IκBβ decreased to 1/3 to 1/2 of the normal vein 6 hours to 24 hours after the surgery and then increased to 5 times that of the control vein 2 weeks after surgery (35%±11% and 44%±13% respectively). Conclusion The NF κB/IκB system is activated in autogenous vein graft. The NFκB may become a new target for the prevention and therapy of intimal hyperplasia and stenosis after vein graft.