佐剂性关节炎大鼠骨密度及滑膜OPG/RANKL蛋白的改变

目的观察佐剂性关节炎大鼠的骨密度及踝关节OPG和RANKL蛋白的表达。方法取SD大鼠,制成佐剂性关节炎模型,设正常组、模型1组、模型2组。观察各组大鼠造模后第7、14、21、28天不同时间点的关节炎指数。第21天处死模型1组全部大鼠;第28天处死正常组和模型2组的全部大鼠,分别检测取大鼠整体右侧胫骨和距胫骨远端约1cm为兴趣区的骨密度,同时取双侧踝关节滑膜Western-blotting法检测OPG/RANKL蛋白的表达。结果模型1组,模型2组和正常组比较,各时间点关节炎指数积分差异均有统计学意义(P<0.01)。模型1组大鼠兴趣区的骨密度较正常组低(P<0.01);模型2组大鼠兴趣区的骨密度较模型1组和正常组均显著降低(P<0.01);3组大鼠整体右侧胫骨骨密度值无明显差异。模型1组,模型2组的OPG蛋白表达与正常组差异均有统计学意义(P<0.01)。模型1组的RANKL蛋白表达与正常组无差异,而模型2组的与正常组相比差异有统计学意义(P<0.01)。结论佐剂性关节炎大鼠在造模后第21天存在胫骨远端骨丢失,第28天该病变更为加重,而同时整体胫骨的骨密度均未发生明显变化。造模后第21天和28天大鼠关节滑膜的OPG蛋白表达降低。造模后第28天大鼠滑膜的RANKL蛋白高于正常。

The changes of bone density and OPG/RANKL protein in adjuvant arthritis rats

Objective To investigate the bone mineral density and the expression of OPG and RANKL protein in ankle of rats with adjuvant arthritis.Methods SD rats were established adjuvant arthritis model and separated into normal group,model 1 group,and model 2 group.Arthritis index was observed in each model group at different time of 7 day,14 day,21 day and 28 day after modeling.Rats in model 1 group were sacrificed at the 21st day,the ones in the normal group and model 2 group were at the 28th day.The bone mineral density of the whole right side of the tibia and about 1cm from the distal tibia called interest region were detected.At the same time,the expression of OPG/RANKL protein of bilateral ankle synovial membranes was inspected by Western-blotting.Results The arthritis indexes of each time point of model 1 and model 2 groups had difference compared with the normal group(P<0.01).The bone mineral density of interest region of model 1 group were lower than that in normal group(P<0.01).The interest region of model 2 group significantly reduced compared with those in the normal and model 1 groups(P<0.01).The overall right tibia bone mineral density had no significant difference.The expression of OPG protein in model 1 and model 2 groups was significantly different compared with the normal group(P<0.01).RANKL protein of model 2 group,not model 1 group,was significantly different compared with normal group(P<0.01).Conclusion Adjuvant arthritis rats lost distal tibial bone 21 days after the modeling,and aggravated in 28 days.While the overall tibia bone mineral density had no difference.The expression of rat synovial OPG protein decreased at the 21st day and 28th day after modeling.At the 28th day after modeling,the expression of rat synovial RANKL protein was higher than the normal.