Morphosis of the epiphyseal plate and expression of vascular endothelial growth factor during healing of injured epiphyses
10.3760/cma.j.issn.0253-2352.2012.06.010
- VernacularTitle:骨骺损伤修复过程中骺板形态及VEGF表达的变化
- Author:
Xuemin LV
;
Hao HU
;
Ming LU
;
Yuan GUO
- Publication Type:Journal Article
- Keywords:
Epiphyses;
Vascular endothelial growth factor A;
Wounds and injuries
- From:
Chinese Journal of Orthopaedics
2012;32(6):570-575
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate morphosis of the epiphyseal plate and the expression of vascular endothelial growth factor (VEGF) in the epiphyseal plate during healing of injured epiphysis.Methods Thirty SD rats aged 4-5 weeks were used to make models of proximal tibia epiphysis injury.These models were equally divided into 5 groups in random,with 6 rats in each group,and these groups of rats were killed separately at 2,4,6,10,21 days postoperatively to harvest the proximal tibia epiphysis,in order to explore the morphosis of the epiphyseal plate and VEGF expression pattern in the epiphyseal plate at different healing phase.The structure of the epiphyseal plate was evaluated by measuring the length of the limb and radiographic examination of the limb.The ratio of length of injured tibia and that of the other side was used to describe the tibia length discrepancy.The micro structure of the epiphyseal plate and situation of the bone bridge in the epiphyseal plate were measured by using Micro CT.By using HE stain and VEGF immunohistochemistry,the changing of chondrocyte and VEGF expression pattern in the epiphyseal plate were observed at different healing phase.Results The limb discrepancy appeared at 4 days postoperatively,became biggest at 10 days postoperatively,and tended to decrease at 21 days postoperatively.Micro CT demonstrated the fibrous bone tissue formation in the epiphyseal plate at about 6 days postoperatively,which became bone bridge finally.HE stain showed chondrocyte in the rest zone had the tendency to aggregate after injury,and the highly ordered structure of chondrocyte in the epiphyseal plate no longer existed,chondrocyte differentiation was accelerated.VEGF immunohistochemistry stain showed the high reaction of VEGF in the epiphyseal plate appeared after surgery,and the positive zone of VEGF expanded through the physis with time,which finally led to angiogenesis and ossification.Conclusion A serial alteration of morphosis of the epiphyseal plate occurred during the healing process.Fibrous bone tissue formation in the epiphyseaL plate could be observed in the early and mid-term of the healing process.With progress of healing,VEGF expression zone gradually expanded across the epiphyseal plate,which is related to the formation of bone bridge.
