[Gene expression of transforming growth factor beta1 in zone II flexor tendon wound healing of rabbit]

Abstract

Objective: To research the gene expression of transforming growth factor beta1 (TGF-beta1) in zone II flexor tendon wound healing of rabbit.

Methods: Sixty New Zealand white rabbits forepaws (left side) underwent complete transection and the middle digit flexor digitorum profundus tendon in zone II were repaired by Kessler methods as the experimental group. The normal right forepaws served as the control group. The tendons and tendon sheaths were harvested at 1, 7, 14, 21, 28 and 56 days after repair (n = 10). The expression patterns of TGF-beta1 were analyzed by in situ hybridization and immunohistochemistry staining methods.

Results: The in situ hybridization examination revealed that TGF-beta1 mRNA expression up-regulated at 1 day, reached the peak levels at 14-21 days and remained high levels up to 56 days in the experimental group. The expression of TGF-beta1 mRNA in control group was lower than that in the experimental group, showing statistically significant difference (P < 0.05). The results of immunohistochemical staining was similar to that of in situ hybridization.

Conclusion: The normal tendon and tendon sheath cells are capable of TGF-beta1 production. The cytokine is activated in tendon wound condition. The up-regulation of this cytokine in both tendon and tendon sheath cells are coincidence with both extrinsic and intrinsic mechanisms for tendon repair.