Corticosterone and glucose are correlated and show similar response patterns to temperature and stress in a free-living bird

Glucocorticoid (GC) hormones have traditionally been interpreted as indicators of stress, but the extent to which they provide information on physiological state remains debated. GCs are metabolic hormones that amongst other functions ensure increasing fuel (i.e. glucose) supply on the face of fluct...

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Detalles Bibliográficos
Autores: Millanes, Paola M., Pérez Rodríguez, Lorenzo, Gallego Rubalcaba, Juan Vicente, Gil, Diego, Jimeno, Blanca
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/118033
Acceso en línea:https://hdl.handle.net/20.500.14352/118033
Access Level:acceso abierto
Palabra clave:598.2
591.1
Glucocorticoids
Energy expenditure
Stress response
Metabolic rate
Sturnus unicolor
Zoología
Aves
Fisiología animal (Biología)
2401 Biología Animal (Zoología)
2401.20 Ornitología
2401.13 Fisiología Animal
Descripción
Sumario:Glucocorticoid (GC) hormones have traditionally been interpreted as indicators of stress, but the extent to which they provide information on physiological state remains debated. GCs are metabolic hormones that amongst other functions ensure increasing fuel (i.e. glucose) supply on the face of fluctuating energetic demands, a role often overlooked by ecological studies investigating the consequences of GC variation. Furthermore, because energy budget is limited, in natural contexts where multiple stimuli coexist, the organisms' ability to respond physiologically may be constrained when multiple triggers of metabolic responses overlap in time. Using free-living spotless starling (Sturnus unicolor) chicks, we experimentally tested whether two stimuli of different nature known to trigger a metabolic or GC response, respectively, cause a comparable increase in plasma GCs and glucose. We further tested whether response patterns differed when both stimuli occurred consecutively. We found that both experimental treatments caused increases in GCs and glucose of similar magnitude, suggesting that both variables fluctuate along with variation in energy expenditure, independently of the trigger. Exposure to the two stimuli occurring subsequently did not cause a difference in GC or glucose responses compared with exposure to a single stimulus, suggesting a limited capacity to respond to an additional stimulus during an ongoing acute response. Lastly, we found a positive and significant correlation between plasma GCs and glucose after the experimental treatments. Our results add to the increasing research on the role of energy expenditure on GC variation, by providing experimental evidence on the association between plasma GCs and energy metabolism.