The Antifibrotic Effects of Plasminogen Activator Inhibitor-1 Antagonists are Observed in Rats with Epidural Fibrosis.

Abstract

Objectives: Epidural fibrosis occurs after laminectomy as part of the local repair mechanisms. Adhesion around the nervous tissue could cause pain and disability. In the current study, we investigated the possible antifibrotic effects of the plasminogen activator inhibitor-1 (PAI-1) antagonists in a rat laminectomy model.

Methods: The rats were randomly assigned to the control, the TM5441, and the TM5484 groups (n=6 per group). In the control group, just a laminectomy was performed. In the treatment groups, intragastric administration of PAI-1 antagonists was done after skin closure. Epidural fibrosis was investigated macroscopically and histopathologically four weeks later.

Results: In the TM5441 and TM5484 groups, the macroscopic epidural fibrosis score was less than the control group (p<0.001 for both groups). Microscopic epidural fibrosis score was also decreased in the TM5441 and TM5484 groups (p>0.05 for both groups). Fibroblast cell density classification scores in the TM5441 and TM5484 groups were lower when compared to the control group (p>0.05 for both groups). Fibrosis thickness was lower in the TM5441 and TM5484 groups when compared to the control group (p<0.01 for both groups).

Conclusion: Plasminogen activator inhibitor-1 antagonists could be a treatment alternative for the prevention of epidural fibrosis.