effects of high frequency electromagnetic radiation (27.12 mhz) on ultrastructure of bone formation in the rat embryos

نویسندگان
چکیده

introduction: the aim of this study was to evaluate the effects of high frequency electromagnetic radiation (27.12 mhz) on ultrastructure of bone inthe rat embryos. material and methods: three experimental groups were formed: experimental group 1 was exposed continuously during the pregnancy periodfrom day 0 through day 6, experimental group 2 from day 7 through day 13 and experimental group 3 from day 14 through day 20 of gestation. these experimental groups were exposed to 10 w/cm2 at 27.12 mhz radiation for 15minutes twice daily for 7 days. total exposure time for each rat was 210 minutes. three sham exposure groups were also exposed to 0 w/cm2 for 15minutes twice daily for 7 days. the control group had no exposure.ultrastructure of mid-diaphysis of tibia from twenty one 21 day old rat embryoswere studied by transmission electron microscope. results: the results showed that colonic temperature of experimental ratswere increased. ultrastructure of mid-diaphysial portion of tibia in the experimental rats revealed cytoplasmic vacuolization and shrinkage,degeneration of some organelles, nuclear condensation in the osteoblasts and decreased of amount of bony trabecula in the extracellular matrix. these degenerative changes were increased in experimental groups especially inexperimental group 2 that received radiation during 7 through 13 days ofgestation. conclusion: the results showed that high frequency radiation caused structural changes in exposed osteoblasts and it retarded bone formation in the rat embryos

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عنوان ژورنال:
cell journal

جلد ۶، شماره ۳، صفحات ۱۳۲-۱۳۷

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