Abstract

Individually consistent behavioral and physiological responses to stressful situations (often referred to as coping styles) has been reported in many animal species. Differences in hypothalamic-pituitary axis reactivity characterize individuals, and it has been proposed that the glucocorticoid (gr) and mineralocorticoid (mr) receptors are fundamental in regulating coping styles. We sorted individuals into reactive and proactive coping styles by collapsing behavioral outputs from net restraint and confinement stress tests in a principal component analysis. We then analyzed plasma cortisol levels, serotonin neurochemistry and the relative mRNA expression of gr1 and mr in stressed individuals per coping style. Proactive fish were characterized as having a lower serotonergic activity and being more active under stress. In addition, proactive fish had higher hypothalamic gr1 and mr abundance and a higher mr/gr1 ratio, compared to reactive fish. We found no significant differences in cortisol or telencephalic mRNA, gr1 and mr expression, or their ratio. Brain MR and GR have been proven to have an important role in the appraisal, coping and adaptation to stressful stimuli, so that a higher expression of these receptors in proactive fish suggests increased tolerance and performance under stress, compared to reactive individuals. We present evidence of a conserved neuroendocrine mechanism associated with coping styles in a fish species which is ecologically very diverse and considered to be the most cold-adapted fish in freshwater. We propose that this may be a first step into exploiting this model in order to better understand climate-change related effects in sub populations and ecophenotypes.

Keywords

Behavior; Cortisol; Glucocorticoid receptor; Mineralocorticoid receptor

Published in

Physiology & behavior
2017, Volume: 177, pages: 161-168
Publisher: PERGAMON-ELSEVIER SCIENCE LTD

SLU Authors

• Magnhagen, Carin

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Brännäs, Eva

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Backström, Tobias

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Nilsson, Jan

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

Conserve and sustainably use the oceans, seas and marine resources for sustainable development
Take urgent action to combat climate change and its impacts


UKÄ Subject classification

Ecology
Zoology
Fish and Aquacultural Science


Publication identifier

DOI: https://doi.org/10.1016/j.physbeh.2017.04.024

Permanent link to this page (URI)

https://res.slu.se/id/publ/90662