PUBLICATION
Cortisol elevation post-hatch affects behavioural performance in zebrafish larvae
- Authors
- Best, C., Vijayan, M.M.
- ID
- ZDB-PUB-170718-7
- Date
- 2017
- Source
- General and comparative endocrinology 257: 220-226 (Journal)
- Registered Authors
- Keywords
- Cortisol, Development, Glucocorticoid receptor, Larval behaviour, Mineralocorticoid receptor, Early-life stress, Zebrafish
- MeSH Terms
-
- Animals
- Hydrocortisone/metabolism*
- Hydrocortisone/pharmacology
- Larva/drug effects*
- Zebrafish*
- Zebrafish Proteins/metabolism*
- PubMed
- 28713045 Full text @ Gen. Comp. Endocrinol.
Citation
Best, C., Vijayan, M.M. (2017) Cortisol elevation post-hatch affects behavioural performance in zebrafish larvae. General and comparative endocrinology. 257:220-226.
Abstract
Maternal cortisol is essential for cortisol stress axis development and de novo production of this steroid commences only after hatch in zebrafish (Danio rerio). However, very little is known about the effect of elevated cortisol levels, during the critical period of stress axis activation, on larval performance. We tested the hypothesis that elevated cortisol levels post-hatch affect behavioural performance and this is mediated by glucocorticoid receptor activation in zebrafish larvae. The behavioural response included measuring larval activity in response to alternating light and dark cycles, as well as thigmotaxis. Zebrafish larvae at 3 days post-fertilization were exposed to waterborne cortisol for 24 h to mimic a steroid response to an early-life stressor exposure. Also, larvae were exposed to waterborne RU-486 (a glucocorticoid receptor (GR) antagonist) either in the presence or absence of cortisol to confirm GR activation. Co-treatment with RU-486 completely abolished the upregulation of cortisol-induced 11β-hydroxysteroid dehydrogenase type 2 transcript abundance, confirming GR signalling. Cortisol-exposed larvae displayed increased locomotor activity irrespective of light condition, but showed no changes in thigmotaxis. This cortisol-mediated behavioural response was not affected by co-treatment with RU-486. Cortisol exposure also did not modify the transcript abundances of GR and mineralocorticoid receptor (MR) in zebrafish larvae. Altogether, cortisol stress axis activation post-hatch increases locomotor activity in zebrafish larvae. Our results suggest that GR signalling may not be involved in this behavioural response, leading to the proposal that cortisol action via MR signaling may influence locomotor activity in zebrafish larvae.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping