【摘要】 [目的]探讨雌激素在骨质疏松性骨折愈合过程中的作用,并通过其对TGF-β表达的影响进一步探讨其作用机制。[方法]选用6月龄雌性SD大鼠54只,分为SHAM组(假手术组)、OVX组(去势组)、补佳乐组。除SHAM组外,其余各组均切除双侧卵巢建立骨质疏松动物模型。去势后8周各组行右股骨骨折建立骨折模型,同时补佳乐组予0.104(mg/kg/d)灌胃。3组均在骨折后第2、4、6、8周处死大鼠后行放射学观察骨痂变化,并采用免疫组织化学方法,观察各阶段骨痂TGF-β的表达变化及积分光密度测定。[结果]①放射学:OVX组骨痂密度影低,8周时OVX组骨折线仍然存在,SHAM组和补佳乐组骨折线模糊甚至消失。②TGF-β免疫组化:OVX组2周时阳性细胞主要是成纤维样间充质细胞和软骨细胞,4周时周围基质阳性着色,8周时成骨细胞及周围类骨质弱阳性着色,肥大的软骨细胞阳性内表达少或无。补佳乐组2周时软骨细胞出现强阳性染色,4周时成骨细胞内阳性染色增强,软骨细胞内很少或无阳性表达,8周时阳性表达主要位于周围类骨质。SHAM组与补佳乐组类似。③TGF-β积分光密度测定:各组在2周时蛋白阳性表达积分光密度值达到峰值,以后逐渐下降,4周后下降明显。不同时间点OVX组积分光密度值均明显低于SHAM组和补佳乐组。[结论]TGF-β是骨折愈合中重要的细胞因子之一,可促进软骨和骨形成、抑制骨吸收,雌激素通过促进TGF-β的分泌,而发挥其促进骨质疏松性骨折愈合的作用。更多还原

【Abstract】 [Objective] To study the effects of Progynova on osteoporosis association with femoral fracture in ovariec-tomized rats and to explore the possible mechanism of estrogen by the influence on the expression of TGF-β. [Methods] Fifty-four SD female rats, aged 6-month-old, were divided into three groups randomly: SHAM group, OVX group, and Progynova group.The osteoporotic model was established by ovariectomy except SHAM group. The right femur was broken by operation at 8 weeks later. Progynova tablets were given through intragastric administration immediately after operation.The rats in three groups were killed at the end of 2, 4, 6, 8 weeks postoperatively respectively for study. The study indices included: immunohisto-chemical SABC and integrated optical density analysis for TGF-β in bone calluses. [Results] ① Radiology: the density of callus in OVX group was low, and at 8th week fracture line still existed, which was blurred or disappeared in SHAM and Progy-nova group. ② Expression of TGF-β: OVX group: at 2nd, 4th weeks, the positive expression of TGF-β was in chondrocyte, fibroblast and matrix, only in 6th, 8th weeks the osteoblast showed positive expression. Progynova group: at 2nd week, TGF-β expressed notably in chondrocytes, at 4th weeks osteoblasts were positive expression whereas the hypertrophy chondrocytes were almost negative. SHAM group: to be familiar with Progynova group. ③ Gray scales scan quantity analysis: TGF-β in bone calluses of three groups hited the top and descended gradually, obviously 4 weeks later. TGF-β of OVX group was always lower than that of other groups in second and further weeks. [Conclusion] TGF-β is strongly expressed in SHAM group and Progynova group than in OVX group, mainly expressing in chondrocytes and osteoblasts during active functional stage and in matrix. It is presumed that TGF-β acts as an important role in stage of bone fracture healing. The possible mechanism of estrogen on promoting osteoporotic fracture healing is that estrogen enhances the expression of TGF-β in callus.更多还原