RESUMO
During the development of the central nervous system (CNS) there is a great possibility of permanent effects in consequence of environmental disturbances. Nutritional deficiency is one of the factors that impair the normal CNS formation. In general, the protein deficiency evokes, beyond the damages in the maturation of nervous system, several consequences in body growth, biochemical maturation, motor function and the major cognitive functions. These effects were observed in undernourished children all over the world. Even in a restricted period, the malnutrition status may evoke permanent impairments in feeding behavior and in metabolism. Rats submitted to malnutrition during development, showed a marked decrease in the number of myelinated fibers. This condition may reflect a failure in the beginning of the wrapping of axons by oligodendroglial processes and/or a delay in the myelin synthesis. Myelin basic protein (MBP) is an intracellular oligodendrocyte protein that is directly related to the formation of the myelin sheath. In this study we verified the temporal pattern of MBP expression, by immunohistochemical and immunoblotting analyses, in a model of protein malnutrition induced during the first half of the lactation period. We showed that MBP expression was impaired in our malnutrition model and that some of the effects were maintained in adulthood, with possible consequences in the maturation of myelin sheath.
