Assessment of changes in senile plaques and cholinergic markers in the brain of mice subjected to a model of neurodegeneration after training attention

Abstract

Throughout the aging process functions decline naturally, but in most cases individuals adapt to these changes and maintain their quality of life and daily activities. However, in the presence of neurodegenerative diseases common to aging, such as Alzheimer's disease (AD), the quality of life may be compromised. Memory is one of the cognitive functions that are impaired in the case of AD. Memory formation does not depend on isolated nerve structures, but rather on the intense connection between structures such as cortex, hippocampus and amygdala. Modulation of memory occurs through the action of neurotransmitters. Here, we stands out the cholinergic system, which plays an important role in formation of LTP (long-term potentiation), which is closed related to long-term memory. Additionally, it has been reported that the nicotinic cholinergic receptor ±7 has active participation in the degradation of amyloid-² peptide. In this project, the amount and density of senile plaques and ±7 nicotinic receptors will be evaluated in the frontal cortex, hippocampus and amygdala of mice submitted to an experimental model of neurodegeneration and a weekly attention training, which promoted memory improvement, as described earlier (Viel et al., Curr.Alzh. Res, 2012). In this model, the animals infused with ±7 nicotinic receptor antagonist, metillycaconitine, showed no improvement in memory. In this way, we intend to evaluate, in more detail, the effects of attention training to the cholinergic system and memory formation, in order to investigate which area of the brain (cortex, hippocampus or amygdala) was inhibited by the chronic infusion of metillycaconitine (or if all of them were inhibited), leading to the lack of memory retrieval. (AU)