掺镁透钙磷石对骨质疏松兔骨缺损的成骨效果

Effect of magnesium-doped calcium hydrogenphosphate dehydrate on osteogenesis in osteoporotic bone defect rabbits

目的探讨掺镁6.67%透钙磷石骨水泥修复家兔骨质疏松的桡骨骨缺损的成骨效果。方法 27只雌性新西兰白兔进行骨质疏松造模,之后随机分为对照组、透钙磷石组、掺镁6.67%透钙磷石组(掺镁6.67%组),每组9只。在双侧桡骨中段制作长15 mm的骨缺损,缺损处对照组不充填任何材料,透钙磷石组植入透钙磷石骨水泥,掺镁6.67%组植入掺镁6.67%透钙磷石骨水泥。于术后4,8,12周,通过肉眼观察、拍摄X线片观察缺损区影像学变化和免疫组化观察血小板源性生长因子(platelet-derived growth factor,PDGF)在缺损区的表达与分布判断骨缺损的修复情况。结果 12周时掺镁6.67%组骨缺损修复基本完成,其余组缺损仍成凹形,掺镁6.67%组成骨效果最佳;免疫组化显示,PDGF在第4周表达最高,8周、12周时逐步降低,4周、8周时,掺镁6.67%组表达比透钙磷石组高,差异具有统计学意义(P<0.05)。结论掺镁6.67%透钙磷石可促进骨质疏松骨缺损的愈合,修复早期可促进PDGF的表达。

Objective To evaluate the effect of 6. 67% magnesium-doped calcium hydrogenphosphate dehydrate on the repair of osteoporotic radius bone defect in rabbits. Methods Twenty-seven female New Zealand rabbits were used to establish osteoporotic bone defect model,and then randomly divided into 3 groups( n = 9 in each group) : control group,calcium hydrogenphosphate dehydrate group and 6. 67% magnesium-doped calcium hydrogenphosphate dehydrate group( 6. 67% magnesium-doped group). All rabbits were defected 15 mm long in bilateral radius. The defect was not filled in blank group,while the defect was filled with 6. 67% magnesiumdoped calcium hydrogenphosphate dehydrate and calcium hydrogenphosphate dehydrate in the other two groups,respectively. The repair of bone defect was observed by naked eyes,the image changes of bone defect was observed by X-ray,and the expression and distribution of platelet-derived growth factor( PDGF) were observed by immunohistochemistry at 4,8,12 week after operation. Results The repair of bone defect was basically completed at 12 week in 6. 67% magnesium-doped group,but remained concave in the other two groups. The effect in 6. 67% magnesium-doped group was the best among three groups. The immunohistochemistry showed that the expression of PDGF was the highest at 4 week,and then decreased gradually. The expression of PDGF in 6. 67% magnesium-doped group was higher than that of calcium hydrogenphosphate dehydrate group at 4,8 week( P < 0. 05). Conclusion The 6. 67% magnesium-doped calcium hydrogenphosphate dehydrate can not only promote the healing of bone defect in osteoporosis but also promote the expression of PDGF in the early stage of repair.