TNFα和VEGF在激素性股骨头坏死中的变化

Change of TNF-αand VEGF on glucocorticoid-induced avascular necrosis of femoral head in rabbits

[目的]通过应用马血清、激素作用新西兰兔,诱导激素性股骨头坏死动物模型,分析TNFα、VEGF在激素性股骨头坏死中的作用。[方法]将20只健康新西兰兔随机分成2组,每组10只。A组为模型组,每只用马血清10 m l/kg,经兔耳缘静脉注射,间隔2周,按5 m l/kg剂量连续2 d注射马血清各1次,间隔2周后,注射醋酸泼尼松龙,按7.5 mg/kg腹腔注射3次。B组:正常对照组。动物注射激素5周后,采血,应用ELISA法测血清中TNF-α浓度。处死模型组,标本进行常规组织病理学检查,免疫组化分析股骨头VEGF的表达。[结果]模型组兔血清TNF-α浓度明显高于正常组(P<0.01)。组织病理学检查显示:部分血管栓塞,骨髓腔内造血组织明显减少,免疫组化结果显示:骨细胞及骨髓组织VEGF表达明显减少。[结论]血清中TNF-α浓度升高及股骨头骨髓组织VEGF表达减少可能是激素性股骨头坏死发生的重要因素。

[ Objective] To establish animal model of avascular necrosis of the femoral head in rabbits induced by glucocorticoid, to further investigate the pathogenesis of glucocorticoid-induced osteonecrosis. [ Method] Twenty New Zealand white rabbits were used and randomly divided into two groups. Group A was injected with horse serum and prednisone. Group B was used as the control. The concentration of TNF-α was measured by ELISA in rabbits serum of group A and group B. Femoral head specimens were studied by histopathologic examination and the expression of VEGF by immunohistochemical examination. [ Result] The concentration of TNF-α in rabbits serum of group A was higher than that of group B（ P 〈 0. 01 ）. In group A, which was featured with defective periosteum, there were osteocytes pyknosis or necrosis, increased numbers of empty bone lacunae and fat cells, decreased hematopeietic tissue and occluded blood vessels compared to normal control group under light microscope and histological staining. The expression of VEGF was decrease in the osteonecrosis. [ Conclusion ] The rising of level of TNF-α and decrease of expression of VEGF may be one of the most important factors in the occurrent of avascular necrosis of the femoral head.