Effect of Nonionizing Radiation onThe Cerebellum of Neonatal Mice • Morphological, Histochemical And Ultrastructural Study

Abstract

Introduction: Although the use of mobile telephones is common, increasing and beneficial, it is still considered as an environmental pollutant nowaday. This is because these devices require to be held close to the head and the exposure effects on the brain remain controversial. Being so, we designed this study. Aim: The present study was done in an attempt to investigate the morphological, histochemical and ultrastructural changes produced in the cerebellum of neonatal mice as a result of exposure to the nonionizing radiation of the mobile phone. Material and Methods: Eleven neonatal mice were used in this study. Five of them were exposed (as experimental group) to mobile phone microwaves (900- 1800 MHz, SAR: 0.92 w/kg) during their late prenatal and early postnatal life (1 hour/day for 30 consecutive days). While the other six served as control animals. Comparable parts of cerebella were removed from all animals and processed for the examination by the light and the transmission electron microscopes. Results: The whole body exposure of the neonatal mice to this type of nonionizing radiation resulted in several morphological, histochemical and ultrastructural changes. These changes included a statistically significant decrease in the mean cell distribution, DNA content and total protein content of Purkinje cells and other cerebellar elements of exposed animals. On the other hand an increase in the Purkinje cell volume was recorded. In addition, the ultrastructural observations were corrugated plasma and nuclear membranes, ruptured mitochondria, destruction of Golgi apparatus , dilatation and disintegration of RER, scarcity of ribosomes and Nissl bodies in Purkinje cells. Damage in the cell membranes, chromatin clumping and increase in electron density of the cells of granular layer also observed. In the molecular layer; degeneration of axons and dendrites, increased electron density and damage of neurons occurred. Conclusion: The whole-body exposure of neonatal mice to the nonionizing radiation produced many pathological lesions in their cerebella at the cellular and subcellular levels.