Banca de QUALIFICAÇÃO: JULIO CESAR DE OLIVEIRA LEAL

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : JULIO CESAR DE OLIVEIRA LEAL
DATE: 08/04/2022
TIME: 09:30
LOCAL: Remoto
TITLE:

Exposure to an abnormal light condition during the lactation phase: effects on behavioral aspects and protein expression in adult Wistar rats.

KEY WORDS:

Constant light; Ontogeny; Rats; Cognition; Mood states.

PAGES: 69
BIG AREA: Ciências Humanas
AREA: Psicologia
SUBÁREA: Psicologia Fisiológica
SPECIALTY: Psicobiologia
SUMMARY:

In adult rats, exposure to constant light condition (LL) leads to uncoupling of the circadian multiple oscillators on the suprachiasmatic nucleus (SCN) and it can produce an arrhythmic pattern on locomotor activity, cognitive and emotional impairments. However, when rats are kept in LL on lactation phase, they develop a circadian rhythm which is maintained for many days after weaning. The aim of this study is to investigate the effect of LL during lactation in cognitive performance, anxiety-like and depressive-like behaviors in adult rats in LL or in a sub-sample of adult rats in LL that kept a long-term circadian rhythm. Male Wistar rats were submitted to LL on lactation phase, from postnatal day 1 (P1) to P22. On weaning, they were transferred to 12:12 light and dark cycle (LD), and on P61, they returned to LL (LL-LD-LL group; n = 8). As a control, a group were maintained in LD 12:12 for the entire experiment (LD-LD-LD; n = 7). ~P107, rats were submitted to an open field test (anxiety-like task), novel object recognition, object-in-place and passive avoidance tests (memory tasks) and sucrose preference test (anhedonia test). Food consumption and body mass were register weekly from the weaning. Finally, rats were euthanized one week after the last behavioral task in order to quantify the expression of c-Fos in the SCN, hippocampus, amygdala and pre-frontal cortex. Our preliminary results showed that 4 rats from LL-LD-LL group kept a long-term rhythm of locomotor activity and 4 rats did not. Moreover, LL-LD-LL showed a higher latency to start the rearing behavior in the open field, and did not show both object recognition and object and location association memory. Finally, LL-LD-LL show a weekly food consumption and body mass similar to LD-LD-LD group. The results for the sub-sample LL-LD-LL group, that kept a long-term circadian rhythm, are the same. Together, these preliminary results indicates that exposure to LL on lactation do not prevents impairments on object and spatial recognition, and this effect is independent of the maintain of a long-term circadian rhythm. More experiments with adaptations on the length of the reexposed to LL are necessary in order to get more conclusive results.

BANKING MEMBERS:
Interna - 2140860 - ROVENA CLARA GALVAO JANUARIO ENGELBERTH
Externa à Instituição - BRUNA DEL VECHIO KOIKE