Effects of pulsed electromagnetic fields on the precursor cells of osteoclasts and osteoblasts

Abstract

Objective To study the in vitro and in vivo effects of pulsed electromagnetic fields (PEMFs) on osteoclast and osteoblast precursor cells.Methods To observe the in vitro effect of PEMFs,femur bone marrow cells of 8 week old female SD rats were collected.According to different treating doses,rats were divided into four treatment groups and one control group.After the treatment,the clones of granuloeyte/maerophage colony forming unit(CFU-GM) and fibroblast colony forming units(CFU-F) were measured respectively.To observe the combined in vitro and in vivo effect of PEMFs,8 week old female SD rats were randomly divided into three groups: 2-70 group,ovariectomization (OVX) group and SHAM group.Rats in the 2-70 group and OVX group were bilateral ovariectomized,while rats in the SHAM group were sham-ovariectomized.12 weeks after ovariectomization,the 2-70 group was exposed to PEMFs while the other groups were left untreated.Then,femur bone marrow cells of the rats were collected.According to the way whether the groups were treated with PEMFs,the cells were divided into six groups: 2-70 with/without treatment,OVX with/without treatment,SHAM with/without treatment.After the treatments,the clones of CFU-GM and CFU-F were measured respectively.Results in vitro effect of PEMFs: Compared with the control group,the CFU-GMin the treated groups reduced while the CFU-F increased.PEMFs effect in vitro and in vivo: The CFU-F in treated groupsincreased,whileno.significantdifferencesofCFU-GMwerefoundamongthegroups.Conclusion PEMFs has inhibitory effect on osteoelast precursor cells and enhances the proliferation of osteoblast precursor cells when simply applied in vitro.When PEMFs was applied in combined manner of in vitro and in vivo,it shows that PEMFs enhance the proliferation of osteoblast precursor cells but has no inhibitory effects on osteoelast precursor cells. Key words: Pulsed electromagnetic fields ; Osteoclasts ; Osteoblasts ; Precursor cells