Avaliação da população astrocitária de CA1, CA3 e giro denteado do hipocampo associada à alteração da atividade mastigatória em modelo murino

Abstract

The masticatory activity has been the subject of scientific studies not only for its participation as a facilitator of the process of ingestion/absorption of food, but also by the possible influence on brain function. The removal of the molar teeth of mice, for example, was capable of causing damage to the spatial location of middle-aged animals submitted to behavioral tests, and aggravated in advanced age, reinforcing the idea that the restriction of this activity accentuates cognitive decline. Faced with such a relevant theme, this work has The objective of this study was to investigate whether the alteration of masticatory activity, induced in a model young murine, influences the laminar distribution of astrocytes in the hippocampus. Like this 15 mice were, over 6 months, distributed into different groups of according to the presentation of the ration. One group received feed in the form of pellets. Another group, interspersed, received pelleted feed followed by feed meal, and the last group, also interspersed, received the pelleted feed, followed by bran and again pelleted. Brain material was extracted, and submitted to immunohistochemical processing and subsequent numerical estimation by Use of the optical fractionator of the laminarly organized astrocyte population in CA1, CA3 and Dentate Gyrus of the hippocampus. As a result, a reduction of the astrocyte population in those animals that had less incentive to masticatory activity in the CA1 region, while there was no difference in the of CA3 and toothed gyre. It was concluded that this result can be explained by the heterogeneity of each hippocampal region, as well as by the connections of the circuit trisynaptic and alternative memory formation.