Establishment Of Steroid-induced Rabbit Femoral Head Necrosis Model And The Analysis Of The Biological Characteristics Of Mesenchymal Stem Cells

Objective: To establish a fast and reliable animal model of the osteonecrosis of the Femoral head for the project group.To assess the proliferation and directional induction ability of mesenchymal stem cells in steroid-induced rabbit femoral head necrosis model.To lay a solid theoretical and practical basis for further experiments.Methods: In this study,we used endotoxin combined with methylprednisolone to establish a model of steroid-induced femoral head necrosis.Firstly,inject 10μg / kg of endotoxin via the ear vein.After 24 hours,inject methylprednisolone 20 mg / kg intramuscularly,and needed to be injected once a day for three consecutive days.And then evaluate the effect of the establishment of the model from the image performance,histology and other aspects.Bone marrow mesenchymal stem cells were taken from control group and model group to assess their biological characteristics,including the detection of the proliferation rate and the investigation of the potentiality to osteoblast,cartilage,adipose and so on.Results: The osteonecrosis model can be safely and conveniently induced by the combination of endotoxin and methylprednisolone.The proliferation rate of bone marrow mesenchymal stem cells was significantly lower in model group than in control group(P<0.05).The positive staining of bone marrow mesenchymal stem cells was observed after directional induction in model group.However,alizarin red,alcian blueand oil red O staining showed that the number of calcium nodules,cartilage and lipoblasts was significantly less in model group than in control group after directional induction.Conclusion: 1.Methylprednisolone combined with endotoxin can induce a typical early rabbit avascular necrosis of the femoral head model with high success rate and good reproducibility.2.The bone marrow mesenchymal stem cells in model group still have biological characteristics.But their proliferation and the formation potentials of bore,cartilage and adipose after directional induction are weaker than in control group.