中文摘要：

目的探讨体外培养情况下脂多糖（lipopolysaccharides,LPS）刺激对小鼠骨骼发育和矿化的影响及其机制。方法分离E18.5 d小鼠跖骨和胫骨,分为空白对照组（Blank组）及LPS组（10μg/m L LPS）。分别于培养后第1、7天照相,计算跖骨和胫骨全长增长率（TL-rate）、矿化带增长率（CZ-rate）、第7天矿化带占骨全长的比例（CZ%）。培养7 d后固定、石蜡包埋切片,臧红固绿和甲苯胺蓝染色观察肥大带宽度、Ⅱ型胶原（collagenⅡ,ColⅡ）、Ⅹ型胶原（collagenⅩ,ColⅩ）免疫组化染色观察软骨细胞分化及TUNEL染色观察软骨细胞凋亡变化。结果与Blank组比较,LPS处理后跖骨和胫骨TL-rate及CZ-rate明显降低（跖骨TL-rate P=0.025;跖骨CZ-rate P=0.019;胫骨TL-rate P=0.010;胫骨CZ-rate P=0.024）。臧红固绿、甲苯胺蓝染色及形态计量显示LPS组胫骨肥大带较Blank组明显变短（P〈0.001）。与Blank组比较,LPS组胫骨的软骨分化相关蛋白ColⅡ、ColⅩ表达降低,软骨细胞凋亡明显增加。结论 LPS通过抑制软骨增生、分化及促进肥大带软骨细胞凋亡来抑制骨骼发育及矿化。

英文摘要：

Objective To determine the effect of lipopolysaccharides（ LPS） on bone development and mineralization of mice using metatarsal and tibia culture. Methods Metatarsals and tibias of embryonic mice at E18. 5 were distracted,and divided to blank group and LPS group which was treated with 10 μg / m L LPS. Images of metatarsals and tibias on day 1 and day 7 were obtained to measure the total length and the calcified zone length using Image Pro Plus software. Then the growth rate of total length（ TL-rate） and calcified zone（ CZ-rate） and the proportion of the calcified zone in the total length（ CZ%） were calculated.After 7-day culture,the tibias were embedded in paraffin. Safranin-O and fast green staining was used to measure the length of hypertrophic zone. Immunohistochemical staining for collagen Ⅱ（ ColⅡ） and collagenⅩ（ Col Ⅹ） was carried out to observe the differentiation of chondrocytes. TUNEL staining was used to observe the apoptosis of chondrocytes. Results Measurement data from Image Pro Plus software showed that both TL-rate and CZ-rate of the metatarsals and tibias were lower in the LPS group than in blank group（ metatarsal TL-rate P = 0. 025; metatarsal CZ-rate P = 0. 019; tibia TL-rate P = 0. 010; tibia CZ-rate P =0. 024）. Safranin-O and fast green staining and bone histomorphometry results showed that the hypertrophic zone of the LPS group was obviously shorter than that of the blank group（ P 〈0. 001）. Immunohistochemical results showed that the expressions of ColⅡand ColⅩ were significantly decreased in the LPS group compared with the blank group. TUNEL staining found more apoptosis in the LPS group. Conclusion LPS inhibits the embryonic bone development and mineralization through inhibiting the growth of hypertrophic zone and differentiation of the chondrocytes and promoting the apoptosis of chondrocytes.