The effect and mechanism of acute and chronic application of electromagnetic radiation from 3g mobile phones on mismatch negativity

With the development of technology, more electromagnetic field (EMF) emitting devices are used in our daily life. It has been claimed that mobile phones may affect the electrical activities of the brain. Furthermore, no studies investigating the effect of 2100 MHz EMF on rat MMN were found. So, in our study we have investigated the effects of acute and chronic administration of 2100 MHz EMF on rat MMN by biochemical (TBARS, 4HNE) and histological (TEM) parameters in addition to the expression of NMDA and AMPA receptors and astrogliosis. One week; cage control (K1), sham (S1), EMF (E1) and 10 weeks; cage control (K10), sham (S10) and EMF (E10) groups (20 rats per group) were used. The electromagnetic field groups were kept in carousels with 2100 MHz EMF for 2 hours per day and sham groups were kept in carousels without EMF. At the end of the experiment, the brain tissues were collected after the MMNs were recorded. The AMPA receptor protein was observed to be significantly lower in the E1 group than K1 and S1 groups and higher in the E10 group than S10 group. Glial fibrillary acidic protein (GFAP) was found to be significantly higher in the E1 group than K1 and S1 groups and lower in the E10 group than S10 group. Mismatch negativity and ERP amplitudes were detected to be lower in the E1 group than K1 and S1 groups and higher in the E10 group than S10 group. In addition, the ERP delta and theta power spectra were lower in the E1 group than the K1 group and the delta and beta power spectra were higher in the E10 group than in the S10 group. Also, it was observed that ERP alpha coherence in E1 group was lower than K1 group, and alpha and theta coherences in E10 group were higher than S10 group. In conclusion, our study showed that EMF may have different effects depending on the duration. When it is administered for a short time, it increases GFAP protein and decreases GluR2 protein, MMN amplitude, power spectrum and coherence and when it is administered for a long time it has just the opposite effects. Key Words: Electromagnetic Field, TBARS, GFAP, Glutamate Receptor, Mismatch Negativity.