Efeitos da aplicação de estressores imprevisíveis sobre a estabilidade cromossômica em zebrafish (Danio rerio)

Abstract

The chronic repetition of stressors may cause imbalances in physiological systems and promote mood changes, considered a precursor to psychological disorders, such as anxiety disorder. In humans, the high level of reactive anxiety associated with stressful situations has been correlated with chromosomal instability, suggesting anxiety and stress as potential genotoxic agents. Therefore, the present study aimed to evaluate the effects of the application of unpredictable stressors associated with the induction of anxiety disorders, on chromosomal stability in adult Danio rerio (zebrafish) individuals. For this, a protocol was applied in order to induce and maintain the animals of the experimental group under stressful conditions and, subsequently, to quantify the presence of micronucleated cells, by means of micronucleus (MN) test, in erythrocytes. The average frequency of MNs was calculated according to the number of MNs per 1000 erythrocytes. The results indicated that there was a significant difference in the induction of micronucleated erythrocytes in the animals of the experimental group, when compared to the control group. The present study demonstrated that the application of unpredictable stressors associated with the induction of anxiety was able to cause cell damage (clastogenic and/or aneugenic effect) in this biological model.