RESUMEN
BACKGROUND: Previous studies have confirmed that nano-hydroxyapatite/collagen (nHAC) and mesenchymal stem cells for repair of bone defect have the ability of bone formation in vivo. OBJECTIVE: To observe the effects of vascular endothelial growth factor (VEGF) and bone marrow mesenchymal stem cells (BMSCs), nHAC composite in the repair of femoral defect in rats. METHODS: Sprague-Dawley rat models of middle part of the femur defect were established and randomly assigned to two groups. Control group was implanted with BMSCs/nHAC composite. Experimental group was implanted with VEGF/BMSCs/nHAC composite. At 2, 4 and 8 weeks postoperation, imaging and histology observation of femoral samples were performed. At 8 weeks postoperation, scanning electron microscopy was performed in new bony callus environment. RESULTS AND CONCLUSION: nHAC composite implantation in the rats did not show rejection or inflammatory reaction. Moreover, bone formed rapidly using VEGF and BMSCs, nHAC composite, which exhibited better bone regeneration capacity compared with BMSCs/nHAC composite. The way of ossification mainly was endochondral ossification. It is presumed that VEGF promoted the formation of local microvessels, differentiation and proliferation of osteoblasts, speeded up the speed of endochondral ossification, shortened bone repair time, and elevated the quality and velocity of osteanagenesis.