Preliminary study of mechanism of delayed early fracture healing in ovariectomized mice
Online published: 2011-07-27
Supported by
National Natural Science Foundation of China, 30872641;Shanghai Research and Development Base Project, 09dz2200500
Objective To observe the early fracture healing in ovariectomized mice, and explore the possible mechanism. Methods Forty female C57BL/6 mice aged 6 weeks were randomly divided into ovariectomy group (OVX group) and sham operation group, with 20 rats in each group. Four weeks after ovariectomy in OVX group, right femur fracture mouse models were established in both groups. Two weeks after model establishment, the fracture healing was observed by X-ray examinations, and Micro-CT was used to measure the volumes of callus and mineral density, observe the angiogenesis and determine the vessel volumes and vessel volume fractions in fracture sites after vessel perfusion. Bone tissue samples were prepared 2 weeks after model establishment, the fracture healing was observed by light microscopy with HE staining, and the expression of vascular endothelial growth factor (VEGF) protein in callus tissues was observed with immunohistochemical staining. Results X-ray examinations and histological examinations of fracture samples indicated that the early fracture healing in OVX group was significantly delayed compared with sham operation group. Micro-CT detection revealed that compared with sham operation group, the volume of callus, mineral density, and number of vessels, vessel volume and vessel volume fraction in fracture sites after vessel perfusion were significantly decreased (P<0.05). It was observed by immunohistochemical staining that the expression of VEGF in callus tissues in OVX group was significantly lower than that in sham operation group. Conclusion The early fracture healing is significantly delayed in ovariectomized mice, which may be related to the reduction of angiogenesis in callus tissues.
Key words: osteoporosis; ovariectomy; fracture healing
ZHAO Jian, ZHAO Qiang, ZHANG Lian-fang, et al . Preliminary study of mechanism of delayed early fracture healing in ovariectomized mice[J]. Journal of Shanghai Jiao Tong University (Medical Science), 2011 , 31(7) : 890 . DOI: 10.3969/j.issn.1674-8115.2011.07.005
/
〈 |
|
〉 |