Effect of High-Dose Steroid Treatment on Adipogenesis and Secretion of PAI-1 in Rats / 대한정형외과연구학회지

ABSTRACT

This study was conducted to invetigate the effect of high-dose steroid administration on adipogenesis and secretion of PAI-1 in rat. Sixty healthy Wistar rats were divided into three groups. Group A consisted of 20 control animals received 5 ml/kg isotonic saline for 1 weeks. Group B consisted of 20 animals received 10 ml/kg of methylprednisolone intraperitoeally for 1 week. Group C comprized 20 animals received 10 ml/kg of methylprednisolone intraperitoneally for 1 week. After the completionof treatment, blood sampling was performed for measurenement of PAI-1 and the animale were sacrificed for histopathologic examination and immunohistochemical study. The PAI-1 protein expressin of femoral heads were evaluated with Western-blotting. Blood level of PAI-1 increased significantly in high-dose steroid treated group(Group B and C) compared to control group. In histopathologic examination, significant fat morrow conversion, fat cell hypertrophy and fat cyst formation were observed in high-dose steroid treated group. Immunohistochemically, PAi-1 expression was sprominent in the fat cells. Protein expression of PAI-1 of femoral heads increased significantly in highdose steroid treated group compared to control group. In lights of above results, it is postulated that increased secretion of PAI-1 from fat cells could play a major role in the pathogenesis of osteonecrosis of the femoral head in rats treated with high-dose steroid.