Sex and estrous cycle dependent changes in locomotor activity, anxiety and memory performance in aged mice after exposure of light at night.

Sex and estrous cycle dependent changes in locomotor activity, anxiety and memory performance in aged mice after exposure of light at night.
Behav Brain Res. 2019 Mar 07;:
Authors: Chakrabarti N
Abstract
Light-at-night (LAN) can affect mammalian behaviour. But, the effects of LAN on aged rodents remain undefined yet. In the present investigation, aged Swiss Albino mice, habituated in regular light-dark cycle, were exposed to bright-light-pulse (1-hr) at night on the day of study followed by experimentations for assessment of locomotor activities in the open field, anxiety in the elevated plus maze and short-term memory for novel object recognition (NOR) in the habituated field. Under without-bright-light exposure, (a) aged proestrous females showed greater locomotor activities and less anxiety than in aged diestrous females, (b) aged males showed locomotor activities and anxiety level similar to aged diestrous females and aged proestrous females respectively and (c) all animals failed to retain in object discrimination memory. LAN exposure exhibited the continual failure of such retention of memory while animals showed free and spontaneous exploration with thigmotactic behaviour having no object bias and/or phobia, but time stay in objects by animals altered variably among sexes and stages of estrous cycle. Overall, the LAN caused (a) diminution in locomotor activities, rise in anxiety and failure of memory for recognition of both fa...

Source: Behavioural Brain Research - March 6, 2019 Category: Neurology Authors: Chakrabarti N Tags: Behav Brain Res Source Type: research