| Objective: As a good method to accelerate bone repaired ,pulsed electromagnetic fields is used in clinical in a wide range.But the mechanism of electromagnetic fields on bone is unclear.The frequency,stimulation time,intensity and pulse shape of PEMFs can influence the therapeutic efficacy.But there is no agreement among many views.At present the main focus is the influence of PEMFs on bone molecul mechanism and gene expression. This experiment is to observe the effects of PEMFs on osteoblast of SD rat in vitro. MTT assay, Alkaline phosphatatase- specific activity assay, tetracycline fluorescence labeling assay were used to observe the effects of PEMFs on osteoblasts' proliferation, differentiation and bone tissue-like formation. We design some experiments to observe the effect of PEMFs' frequency and intensity on osteoblasts' proliferation,differentiation.Through the experiment results make statistic analysis and seek the best parameter for treatment. Methods and results:1. PEMFs circuit was designed and improved.The outputs ofPEMFs were sub-impulse groups with frequency of 15Hz and delay time of 5 ms.The intensity of PEMFs could be continuously adjusted from 0 to 15 X 10-4 T.The outputs of reformed PEMFs were sub-impulse groups with frquency of 1Hz and delay time of 30 ms,The intensity of PEMFs was 15 × 10-4 T.The diameter of winding was 100mm.2. Osteoblast isolated and culturedThe osteoblast isolated from calveria bone of SD rat .By means of morphologic observation,staining of ALP and bone nodule formation,the cell demonstrated to be a classical characteristic osteoblast.3. PEMFs had significant stimulatory effect on the cell proliferation,differentiation and bone nodule formation of cultured osteoblast in vitro.4. There were no significant difference in cell proliferation and differenation between 1Hz and 15Hz..There were no significant difference in cell proliferation and differenation under the intensity of 2× 10-4 T and 8× 10-4T.But there were significant difference in cell proliferation and differenation between 15×10-4 T and 2 × 10-4T or 8× 10-4T.Moreover,The intensity of 15 × 10-4T PEMFs inhibit the cell differentiation.Conclusion:PEMFs have some preventable and therapeutic effect for osteoporosis in the prophase study.In this experiment ,we find PEMFs can stimulate the osteoblast cell proliferation, differentiation and bone nodule formation,There were no "windows" effect found between 1Hz and 15Hz.The intensity of 15 X 10-4T PEMFs can obviously accelerate...
|
PDF Full Text Request