Serum Concentration of Growth Factors in Dogs under Different Conditions of Distraction Osteogenesis.

Concentrations of insulin-like growth factors 1 and 2 (IGF-1 and IGF-2), stem cell factor (SCF), vascular endothelial growth factor (VEGF), and transforming growth factor β1 (TGF-β1) were measured in the blood serum of dogs subjected to experimental lengthening of shin bones. In animals subjected to shin bone lengthening at a rate of 1 mm/day in 4 steps, the concentrations of SCF and TGF-β1 significantly increased in the middle of distraction and IGF-1 concentration increased by the end of distraction. In animals subjected to lengthening at a rate of 1.5 mm/day in 6 steps, the levels of IGF-1 and TGF-β1 significantly increased in the middle of distraction and the concentration of IGF-2 at the end of distraction. In animals subjected to lengthening at a rate of 3 mm/day in 120 steps, the concentrations of IGF-1 and TGF-β1 significantly decreased in the middle of distraction and concentrations of IGF-1, VEGF, and TGF-β1 increased by the end of distraction.