摘要
Objective： To observe serum and callus leptin expression within the setting of fracture and traumatic brain injury （TBI）.Methods： Atotal of 64 male SD rats were randomized equally into 4 groups： nonoperated group, TBI group, fraeture group, and fracture＋TBI group. Rats were sacrificed at 2, 4, 8 and 12 weeks after fracture＋TBI. Serum leptin was detected using radioimmunoassay, and callus formation was measured radiologically. Callus leptin was analyzed by immunohistochemistry.Results： Serum ieptin levels in the fracture group, TBI group and combined fracture＋TBI group were all significantly increased compared with control group at the 2 week time-point （P〈0.05）. Serum leptin in the combined fracture ＋TBI group was significantly higher than that in the fracture and TBI groups at 4 and 8 weeks after injury （P〈0. 05）.The percentage of leptin-positive cells in the fracture＋TBI callus and callus volume were significantly higher than those in the fracture-only group （P〈0.01）.Conclusions： We demonstrated elevated leptin expression within healing bone especially in the first 8 weeks in a rat model of fracture and TBI. A close association exists between leptin levels and the degree of callus formation in fractures.
