Accumulation of Silver Nanoparticles in Mice Brain Parts and the Harmful Effects

The influence of the daily prolonged administration of silver nanoparticles on cognitive functions of model mammals was studied. The accumulation of silver in whole brain, hippocampus, cerebellum, cortex and residual part of mice brain was investigated by highly precise and representative Neutron Activation Analysis and the histological studies were conducted in the present research. Some of the main results of the comprehensive study are the description of the biokinetics of silver in the hippocampus, cerebellum and cortex, the finding of the jump increase of silver in the hippocampus and cerebellum after the period of administration of 120 days. Accumulation of silver in the mice brain and hippocampus itself as well as the integrity violation of the CA2 subregion caused long-term contextual memory impairment at 180 days of silver nanoparticle exposure. However, destruction of CA2 had started 60 days before the visible changes in behavior appeared. Complex of the three types of the approach let us find the cognitive impairment and understand the reasons of it.