CONICET | Buscador de Institutos y Recursos Humanos

NOISE-INDUCED RAT HIPPOCAMPAL OXIDATIVE CHANGES WERE INVERTED AFTER REARING IN AN ENRICHED ENVIRONMENT. CORRELATION WITH BEHAVIORAL ALTERATIONS. S. J. MOLINA1, M. MICELI1, F. CAPANI2, L. R. GUELMAN1; 1Dept. Farmacologia, Fac Med, UBA-CEFYBO-CONICET, Buenos Aires, Argentina; 2Lab. de plasticidad y citoarquitectura neuronal, ININCA-CONICET, Buenos Aires, Argentina. Hippocampal-related behavioral alterations were observed in noise-exposed rats. However, a correlation with hippocampal oxidative status was only evaluated in animals exposed at 15 days. Therefore, the aim of the present work was to test if behavioral alterations induced by noise exposure in younger animals might be also related with hippocampal oxidative changes. The possible prevention of these changes through the use of an enriched environment (EE) was also assessed. 7-days-old rats were exposed for 2 h to white noise (95-97 dB). After weaning, rats were transferred to an enriched cage with toys, a wheel, tunnels and ramps, whereas other groups stayed in standard cages. After one week, different behavioral tests were performed and levels of Trx-1, a member of the family of the antioxidants thioredoxins, were also evaluated.Results show that Trx-1 levels were decreased in exposed animals and increased after EE rearing. Moreover, whereas noise-exposed animals showed an increase in risk assessment behavior (RAB), with no changes in associative memory (AM), EE rearing restored RAB and increased the performance in AM.These findings suggest that an oxidative imbalance might be triggered after noise exposure that might underlie RAB alteration. The increase in AM performance in exposed animals reared in an EE might be correlated with a more reduced cellular milieu, suggesting that EE could be a useful strategy that might allow animals to cope with an unfavorable condition.This work was supported by PIP00323 and UBACYT 20020120100149. SJM and MM have CONICET and UBA fellowships, respectively.