Studio dell'effetto delle radiazioni non ionizzanti sul processo di maturazione e differenziamento dei granuli cerebellari di ratto neonato: studi in vitro e in vivo

The purpose of this study is to examine the effect of Extremely Low Frequency electromagnetic Fields (ELF) on the differentiation of cerebellar granule neurons. These cells represent the main population of the rat cerebellum and is one of the most widespread models for the study of numerous neuronal parameters(Balazs et al.,1988; Gallo et al.,1987; Contestabile 2002). In this research I studied cerebellar granule neurons, in experiments in vitro and in vivo. In the first case I analyzed the effects induced by the exposure to electromagnetic fields on primary cerebellar granule neurons of newborn rats, which were eight days old. In the second case I exposed pregnant rats, for the entire duration of the gestation and I sacrified the newborn rat after eight days of exposure. In both cases the cells exposed to the electromagnet fields of 50 Hz, 1 mT showed one premature reaction to Glutamate toxicity test. Moreover the Patch clamp technique showed an increase of the currents of the KAINATO in the exposed cells. These two techniques showed a premature and greater activity of glutamate receptors in the exposed cells. The study of expression of ionotropic glutamate receptors confirmed, by means of Western blotting and RT-PCR, their precocius expression in the exposed cells. These receptors represent an index of maturation of the cerebellar granule neurons (Hack and Balazs 1994), therefore I studied another important neuronal marker, the protein NF-200, one of the three proteins of the neurofilament. Immunofluorescence assay and Western blotting showed one greater expression of this marker in the exposed cells compared to control cells. All these results indicate that the electromagnetic fields of 50Hz and 1 mT can interact with biological material, in fact in my research I demonstrated that the exposure to this physical agent is able to induce a premature maturation and differentiation of cerebellar granule neurons.