RT journal article
T1 Arginine Vasotocin and Cortisol Co-regulate Vasotocinergic, Isotocinergic, Stress, and Thyroid Pathways in the Gilthead Sea Bream (Sparus aurata)
A1 Martos Sitcha, Juan Antonio
A1 Cadiz, Laura
A1 Gozdowska, Magdalena
A1 Kulczykowska, Ewa
A1 Martínez-Rodríguez, Gonzalo
A1 Mancera Romero, Juan Miguel
A2 Biología
K1 arginine vasotocin
K1 cortisol
K1 Crh
K1 isotocin
K1 receptors
K1 Sparus aurata
K1 stress
K1 thyroid system
AB In teleosts, a complex interaction between several endocrine axes modulatesphysiological functions related to metabolism, stress, and osmoregulation. Althoughmany studies in fish underline the interconnection between the hypothalamic–pituitary–interrenal (HPI) and hypothalamic–pituitary–thyroid (HPT) endocrine axes, theirrelationship with the vasotocinergic and isotocinergic systems remains unknown. Theaim of the present study is therefore to shed light on the potential cross-regulationsbetween HPT, HPI, and the vasotocinergic and isotocinergic axes in gilthead sea bream(Sparus aurata) at hypothalamic, hypophyseal, and plasma levels. Sea breams wereadministered with intraperitoneal slow-release implants containing different doses ofvasotocin (the active peptide in vasotocinergic system) or cortisol (the last componentof HPI axis). Plasma osmolality was higher in active neuropeptides vasotocin (Avt)-treated fish, indicating an osmoregulatory function of this hormone. Low concentrationsof Avt increased hypothalamic arginine vasotocin precursor (avt) mRNA levels andincreased Avt storage in the pituitary. Avt treatment down-regulated hypothalamicarginine vasotocin receptor v1a-type (avtrv1a), suggesting a negative paracrine coregulationof the HPI axis due to the close location of avtrv1a and adrenocorticotropinhormone (Acth) cells in the anterior pituitary. Furthermore, the up-regulation observedin arginine vasotocin receptor v2-type (avtrv2) suggests their involvement in metabolicand cortisol-related pathways in the hypothalamus. The decrease in isotocin (It) pituitarystorage and the up-regulation of it receptor, observed in the Avt-treated group, reinforcethe idea of an interconnection between the vasotocinergic and isotocinergic systems.Cortisol and Avt administration each inhibited the HPI axis, down-regulating crh geneexpression in the absence of variations in corticotropin releasing hormone binding protein (crhbp). Finally, both hormonal treatments activated the HPT axis via upregulationof trh and down-regulation of thrb. Our results provide evidence for stronginteractions among the Avt/It, HPI, and HPT axes of marine teleosts, particularly at thehypothalamic level.
PB Frontiers Media SA
SN 1664-042X
YR 2019
FD 2019-03
LK http://hdl.handle.net/10498/21172
UL http://hdl.handle.net/10498/21172
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 21-sep-2026