Objective: To observe the alterations of hypoxia inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF) and CD34 in synovial tissues in rats with adjuvant arthritis and explore the mechanism of angiogenesis in rheumatoid arthritis.
Methods: Thirty SD rats were randomly divided into normal control and model groups. Adjuvant arthritis was induced using Freund's complete adjuvant in the rats of the model group. Nineteen days after the modeling, the expressions of HIF-1α, VEGF and CD34 were detected using immunohistochemistry. The mRNA and protein levels of HIF-1α and VEGF were detected by reverse transcription PCR and Western blotting, respectively.
Results: Compared with the normal control group, the model group showed paw swelling, increased arthritic index, and significantly up-regulated expressions of VEGF, HIF-1α, CD34 in synovial tissue. VEGF mRNA was positively correlated with paw swelling degree, HIF-1α protein was positively correlated with the arthritis index, and VEGF mRNA and HIF-1α protein were positively correlated with CD34.
Conclusion: The synovial angiogenesis is associated with the over-expressions of VEGF, HIF-1α and CD34 in rats with adjuvant arthritis.