Sex differences in skilled movement in response to restraint stress and recovery from stress

Abstract

Sex differences exist in skilled movement, and skilled motor performance is also influenced by stress. As shown for cognitive function, the effects of stress are usually characterized by considerable sexual dimorphism. The purpose of this study was to investigate sex differences in skilled motor function in response to stress. Male and female Long-Evans rats were trained and tested in skilled reaching and skilled walking tasks. Both groups of animals were then exposed to daily restraint stress for 15 days. Recovery from daily stress was assessed by comparing reaching performance at 10 min versus 60 min after restraint stress, and recovery from chronic stress was tested for 21 days after cessation of stress. Animals were tested daily in skilled reaching for the entire period. Observations showed that females performed significantly better than males during the stress period in terms of reaching success and number of attempts needed to grasp a food pellet. No difference between testing at 10 or 60 min after daily stress was found. Analysis of movement patterns and recovery from stress indicated that males and females use different strategies to overcome stress-induced motor disturbance. While male rats preferred to use original movement patterns, females tended to modify these patterns in order to increase reaching success. Modification of movement patterns in female rats was accompanied by a faster recovery in success rate after the cessation of stress. These results indicate sex differences in skilled reaching in response to stress, and in the recovery period after stress.

Genomic and Epigenomic Responses to Chronic Stress Involve miRNA-Mediated Programming

“…There also were no differences between stress and control animals after two weeks of recovery from stress. These results are consistent with previous results showing an absence of body weight gain after two weeks of restraint [11]. Moreover, Jadavji and Metz (2008) showed corresponding behavioural changes in motor performance, which were confirmed by the present study.…”

“…Our previous data suggest that 20 minutes of chronic mild psychological stress, induced by restraint, causes lasting impairments in skilled movement and balance in rats [10], [11]. Considering that motor impairments in male rats persist even after the cessation of the stressor [11], it is possible that epigenetic mechanisms may be involved to permanently alter movement performance via genomic changes in motor areas.…”

“…Considering that motor impairments in male rats persist even after the cessation of the stressor [11], it is possible that epigenetic mechanisms may be involved to permanently alter movement performance via genomic changes in motor areas. The largest and one of the most important motor regions is the cerebellum, which contributes to the learning and coordination of skilled movements [12].…”

Blockade of Mineralocorticoid and Glucocorticoid Receptors Reverses Stress-Induced Motor Impairments

“…The present findings support the feasibility of skilled reaching tasks in rats as a sensitive model to investigate the mechanisms of corticosteroid actions in motor control. Furthermore, in line with earlier data motor performance in both males and females is significantly affected by acute and chronic stress [25]. According to the previous findings, fine motor control in male and female rats was equally susceptible to the disrupting effects of stress and CORT and responded to pharmacological intervention.…”

“…In rat models of stroke and Parkinson’s disease, both stress and CORT can impair motor recovery [21,24] and exaggerate loss of movement [22], respectively. Notably, the motor system shows sexual dimorphism in response to stress [25]. Both MR and GR are liable candidates to account for at least some of these effects.…”