高压氧对激素性股骨头坏死兔血中TF、TNF-α的影响

Effects of hyperbaric oxygen on TF, TNF-α in. the rabbit model of steroid-induced avascular osteonecrosis of femoral head

目的通过研究激素性股骨头坏死（steroid-induced avascularnecrosis of the femoral head，SANFH）兔血组织因子（TF）和肿瘤坏死因子（TNF-α）的动态变化及高压氧（hyperbaric oxygen，HBO）对其影响，探讨SANFH发生机制和高压氧治疗的作用机制。方法健康新西兰白兔78只，按数字随机表法分为3组：正常对照组（N组）7只，模型组（M组）41只，高压氧组（HBO组）30只。模型组又分为造模即刻组（M0组）10只，造模2周组（M2组）10只、造模4周组（M4组）10只、造模6周组（M6组）11只。HBO组分为：2周HBO组（HBO2组）7只、4周HBO组（HB04组）11只、6周HBO组（HBO2组）12只。采用注射内毒素加甲强龙的方法对模型组及HBO组进行造模处理，HBO组在制模后开始HBO处理，每天1次，并于制模2周、4周、6周分别取静脉血检测TF、TNF-α的变化，于相应取血时间点取血后处死实验动物，取双侧股骨头组织进行组织学观察。结果M各组TF[M0：（281．42±46．71）pg／ml，M2：（242．25±131．87）pg／ml，M4：（176．39±66．39）pg／ml，M6：（121．32±107．70）pg／ml]、TNF—OL[M0：（418．83±75．99）pg／ml，M2：（424．41±57．01）pg／ml，M4：（424．05±136．44）pg／ml，M6：（344．34±112．89）pg／ml]均高于N组[TF：（137．55±21．65）pg／ml，TNF-α：（312．174-31．12）pg／ml]，P〈0．05或P〈0．01；而HBO各组与M各组同时间点比较其表达均降低，P〈0．05或P〈0．01；组织学结果：N组股骨头组织形态正常，M组股骨干骺端髓腔内骨髓组织脂肪细胞增多增大、可见变性及片状坏死、炎性细胞浸润、出血、水肿及微小血管血栓、骨髓腔纤维化、造血细胞减少、股骨头萎缩明显；HBO各组脂肪变性、坏死出现率与M组比较明显减少，骨小梁问骨髓炎症反应明显减轻，未见到血栓形成，可见到骨母细胞活跃增生、骨髓纤维化、新生骨形成、股骨头萎缩不明显、骨基质正常。结论兔SANFH时血中TF、TNF-α含量增高，诱导了体内凝血反应，使股骨头处血栓形成，HBO治疗可抑制实验动物体内TF、TNF-α的释放，从而改善凝血功能的异常，治疗股骨头坏死。

Objective To investigate dynamic changes in serum TF and TNF-α in the rabbit model of steroid-induced avascular osteoneerosis of femoral head （ SANFH ） and also to explore the mechanism of SANFH, as well as effects of hyperbaric oxygen （HBO） on SANFH. Methods Seventy-eight New Zealand male rabbits were randomly divided into 3 groups ： the normal control （ group N） （7 animals） , the model group （group M） （41 animals） and the HBO group （group H） （30 animals）. The model group was subdivided into the immediate model group （the M0 group） （10 animals）, the two-week model group （the M2 group） （10 animals）, the fourweek model group （the M4 group） （10 animals） and the six-week model group （the M6 group） （11 animals）. The HBO group was further divided into the 2-week HBO therapy group （HBO2） （7 animals） , the 4-week HBO therapy group （ HBO4 ） （ 11 animals） and the 6-week HBO therapy group （ HBO6 ） （ 12 animals）. Through injection of endotoxin and methyl-prednisolone, rabbits in the group HBO2, HBO4 and HBO6 received HBO therapy 1 hour daily from the second day of the experiment. The durations of HBO therapy were 2 weeks （ HBO2 ）, and 4 weeks respectively. The animals were sacrificed after blood samples were taken at respective blood collection time. Then, levels of TF, TNF-α in the serum were measured and the histological changes in the femoral heads were observed. Results Levels of TF and TNF-α in group M0 increased significantly, when compared with those of group N （P 〈0.05 or P 〈0. 01 ）, while for the HBO subgroups the expression of TF and TNF-a measured at the same time points all decreased, when compared with that of the model subgroups（P 〈0. 05 or P 〈0. 01 ）. To elaborate, TF levels in group Ms and M4 were much higher than those in group HBO2 and HBO4 （P 〈 0. 01 ）. TF level in group M6 was higher than that in group HBO6 （P 〈 0. 05 ）. TNF-α in group M0 also increased significantly, when compared with that in group N （ P 〈 0.01 ）. TNF-α levels in group M2 and M6 were also much higher than those in group HBO2 and HBO6 （ both P 〈 0. 01 ）. TNF-α in group M4 was higher than that in group HBO4 （P 〈 0. 01 ）. Histological examination revealed that tissues of the femoral heads in group N were normal, osteonecrosis and thrombus could be noted in group M2 and M4, hyperplasia fibrosis could be found in group M6 , and osteonecrosis in HBO2 and HBO4 groups seemed less severer than that in Ms and M4 groups, no thrombi in HBO2 , HBO4 groups were noted, and growth of new bones were detected in HBO4 and HBO6. Conclusions The levels of TF and TNF-α levels increased in the rabbit model of SANFH, inducing blood coagulation. Thrombosis at the femoral heads was one of the causes of SANFH. HBO therapy could inhibit the release of TF and TNF-α, thus improving the abnormality of blood coagulation and enhancing treatment of osteonecrosis.