Effects Of Mobile Phone Radiation On Optic Tectum Development In Chick Embryo

The widely usage of mobile phones has raised public health concern about their deleterious effects induced by the radiation. Because of its close even proximatety to the user's head, in addition that the nervous system is more sensitive to mobile phone radiation, it became a focal point to investigate the effects of mobile phone radiation on nervous system. The optic tectum, known as the rostral part of the dorsal midbrain, constitutes one of the principal retino-recipient areas of the central nervous system. Furthermore, the developmental cycle of chick embryo is short to 21days, so that it is significant to research the effects of mobile phone on chick embryo optic tectum for the study of effects on nevous system development.Our study is to evaluate the influence of mobile phone radiation to the morphological changes and neurogenesis on optic tectum in developmental chick embryo,and elucidate the mechanism of radiation on nevous system. The chick embryos were randomly and evenly divided into CG(control group) and RG(radiation group),which were irradiated by mobile phones(900/1,800 MHz,SAR- 1.07W/kg) 4h per day from E2 to E21 of the incubation in the present study. Anatomy, light microscope, electron microscope technique, single cell gel electrophoresis, immunohistochemistry and Western blot were used to study the effects to derminine whether mobile phone radiation influences nervous system development. The result includes the following points.1. Both the mortality and abnormality rate in RG displayed a significant increase compared to CG by statistics;the weight of brain in RG were lower than CG in E6 and E8,but higher than CG in E10,E13,E15 and E21.2. The morphological' observations in light scope and electron microscope in RG had showed obvious changes in early embryo development compared to CG, such as the migration track widening,apoptosis and un-integrated synapse. In middle stage, mobile phone radiation induced the disruption of lamina g, glial cells increase, karyotype abnormalty and the vacuolization of endoplasmic reticulum. On the E21 when hatched, mobile phone radiation caused nuclear membrane uncompletely, myelin sheath defluxion, BBB destruction and heterochromatinization, g nearly disappeared with h/j thicken.3. The DNA damaged rate in tectum cells was significantly higher in RG than in CG in E6 chick embryo(P<0.05).By E21, the damaged rate was still higher in RG(P<0.05), and compared to E6, it showed a much more significant difference(P<0.01).4. In RG, PCNA expression was significantly lower than that of CG in E6, E8 and E10(P<0.05). Brdu-positive showed the same result as PCNA, except that there was no significant difference in E10. Furthermore, the migrating Brdu-positive cells of RG was less and distributed nearer the neuroepithelial layer than that of CG in E8 and E10.5. Western blot showed that STATl expression in RG was much higher than CG in E6 and E10 opposite to PCNA. But in E8, both PCNA and STATl was significantly lower in RG.In conclusion, the data obtained above suggest a role for mobile phone in brain development in chick embryo, which induced morphological changes and DNA damages in tectum cells, it also reduced neurogenesis by inhibiting the proliferation and migration and accelerating apoptosis, indicating that mobile phone radiation may repress the nervous system development participated with many signal pathways, the mechanism remains to be further investigated.