Plasticidade de modalidade cruzada em córtices sensoriais adulto

Abstract

The central nervous system (CNS) neural circuitry is highly dynamic and is continuously modified by sensory experience, in a process we call neuroplasticity, which gives the CNS the ability to adapt to changes in the sensory periphery and / or in response to environmental stimuli . This ability of the CNS remains lifelong, although it is more intense during early stages of development, especially during the critical plasticity period. The main goal of the present work was to evaluate the effects of bilateral sensory deprivation on cross modal neuroplasticity in the visual, somatosensory, and auditory primary cortices od adult rats. Animals (Rattus novergicus) (authorization CEUA/UFPA: 141-13) were divided into three experimental groups: a control group (CTL), an unimodal deprivation group (DEP), in which the animals were subjected to visual deprivation by bilateral enucleation, and a bimodal deprivation group (DDEP), whose animals were submitted to both visual and whisker deprivation bilaterallly. After 60 days of sensory deprivation, the rats were perfused and the brains were sectioned in the coronal plane for immunohistochemistry procedures aimed at revealing the activation of immediate early genes (c-Fos). The results showed that after bilateral visual deprivation the number of c-Fos+ neurons decreased in the visual cortex (** p < 0.0056), increased in the auditory cortex (** p <0.0099), and had no effect in the somatosensory cortex. Bilateral visual and whisker deprivation decreased the number of c-Fos+ neurons in the visual cortex (* p <0.0268) but did not have any effect in the somatosensory and auditory cortices.