Effect of salsolinol on ACTH and cortisol response to handling stress in early anestrous sheep

Abstract

Hasiec M., Szlis M., Chmielewska N., Górski K., Romanowicz K., Misztal T. (2017): Effect of salsolinol on ACTH and cortisol response to handling stress in early anestrous sheep. Czech J. Anim. Sci., 62, 130-139.Inhibition of hypothalamic-pituitary-adrenal (HPA) axis activity by salsolinol was demonstrated in lactating sheep. We assessed whether salsolinol regulates, besides lactation, also adrenocorticotropic hormone (ACTH) and cortisol release, and if its action is prolactin-dependent. We examined two groups of early anestrous sheep, which received for three days salsolinol or vehicle-only intracerebroventricular injections, and a group of lactating sheep injected with the vehicle only. On day 3, blood samples were collected for over six hours and the anterior pituitary was dissected. Plasma ACTH, cortisol, and prolactin concentrations, and proopiomelanocortin (POMC) and prolactin (PRL) mRNA expression within the anterior pituitary were assayed. In all groups, ACTH and cortisol concentrations were higher (P < 0.05 and P < 0.001) during the first half of sampling than in the second half; there were no differences in prolactin concentration. Lactating sheep had lower (P < 0.05 and P < 0.001) plasma ACTH and cortisol concentrations and higher (P < 0.001) plasma prolactin concentration than both groups of anestrous sheep during the first half of sampling. In the second half, there were no differences in ACTH and cortisol concentrations between all groups, but prolactin concentration was still higher (P < 0.001) in lactating animals. Salsolinol treatment decreased ACTH and cortisol concentrations during the first half of sampling (P < 0.05 and P < 0.001) compared to the anestrous controls, but had no effect on prolactin concentration. POMC mRNA expression was lower (P < 0.05) and PRL mRNA expression was higher (P < 0.05) in lactating sheep than in anestrous sheep. Salsolinol did not affect POMC and PRL mRNA expression. In conclusion, increased ACTH and cortisol concentrations during the first half of sampling occurred in response to handling stress. Salsolinol inhibited the HPA axis response to stress in early anestrous sheep, and it was unrelated to prolactin secretion.

Adaptive Modifications of Maternal Hypothalamic-Pituitary-Adrenal Axis Activity during Lactation and Salsolinol as a New Player in this Phenomenon

“…However, these studies did not examine changes over a 24-hour period. Studies performed in our laboratory also suggested the lack of differences in basal plasma ACTH and cortisol concentrations between midlactating and anestrous or postweaning sheep [ 28 , 29 ]. Furthermore, a study on Japanese macaques ( Macaca fuscata ) showed that lactating females had even lower fecal glucocorticoid concentrations than cycling females during the mating season [ 30 ].…”

“…In order to verify this observation, we conducted serial salsolinol intracerebroventricular injections in anestrous sheep subjected to handling stress at the turn of winter and spring, when prolactin secretion was significantly reduced [ 13 ]. As a result of salsolinol injections, sheep had lower ACTH and cortisol response to stress compared to vehicle-treated animals, but there were no changes in plasma prolactin concentration, confirming that salsolinol action in regard to the HPA axis occurred without prolactin mediation [ 29 ]. Oxytocin should also be considered as a potential mediator of the discussed phenomenon, since salsolinol can mediate suckling-induced release of this hormone in lactating sheep [ 113 ]; however, it still remains to be investigated.…”

Interactions between corticotropin releasing factor signaling and prophylactic antibiotics on measures of intestinal function in weaned and transported pigs

“…For analyses of blood parameter data during the transport phase, injection treatment (CRFA and SAL), collection time [pre-transport ( Pre-T ) and post-transport ( Post-T )], and their interactions were used as fixed effects. The time it took in seconds to take blood (measured from the moment the pig was handled to the end of blood collection) was used as a covariate when significant ( p ≤ 0.05) for plasma cortisol and ACTH levels because animal handling time directly influences ACTH and cortisol release ( Hasiec et al, 2017 ; Rocha et al, 2019 ).…”

Response to selection of a breeding program for Suffolk sheep in the Czech Republic

“…It is also one of the leading sheep breeds used for meat on a global scale (Rasali et al 2006;Maximini et al 2012). Sheep known as animals with year-seasonal oestrus activity depending on daylight conditions (Hasiec et al 2017;Molik et al 2017) are limited in their productive traits for https://doi.org/10.17221/21/2018-CJAS non-prolific period. Therefore, the effort is aimed at improving lamb growth abilities; especially in breeds intended for paternal position in breeding scheme for meat production.…”