Prejuízos na interação social do camundongo mutante equilíbrio: redução da memória olfatória, percepção espacial e da área de astrócitos no colículo superior e aumento na atividade da serotonina no córtex frontal

Resumo (EN)

The recessive mutant mouse, called equilibrium (eqlb), presents balance deficiency and motor incoordination and was developed using the chemical agent N-ethyl-N-nitrosourea (ENU). The genetic mapping identified the mutation in the NADPH oxidase 3 (Nox3) gene, chromosome 17, described as responsible for vestibular defects and in the formation of otoconia. It was observed that these mice, among other deficits, did not present aggressive behavior among males suggesting impairment of their social behavior. The objective of this study was to investigate the social behavior of eqlb mice and to identify which or which would be the causes that would lead to the absence of this type of aggressiveness. Eqlb and BALB / c mice were evaluated to the: 1) social and aggressive behavior of males in stable colonies and front of an intruder; 2) social / aggressive behavior by isolation; 3) olfactory memory; 4) spatial perception. 5) levels of serotonin and metabolite in the frontal cortex, 6) index by area of astrocytes in the superior colliculus. In relation to the BALB / C mice, the eqlb mice showed: 1) lower social interaction between animals in stable colonies; 2) greater social interaction with the intruder being attacked for longer by the intruder; 3) when isolated they interacted less with the intruder and explored more the cage; 4) greater latency in the olfactory test; 5) greater immobility in the tail suspension test; 6) higher activity of the serotonergic system of the frontal cortex and 7) reduction in the index by area of astrocytes in the superior colliculus. Conclusions: it is suggested that the lower social interaction in the stable colony, the greater social interaction with the foreign mouse as well as the absence of response to the aggression of the mouse eqlb to intruder may be a consequence of olfactory memory deficits, spatial perception, increased activity serotonergic in the frontal cortex and reduction of the index by astrocyte area in the superior colliculus.