TY - JOUR
T1 - Stress‐Related Changes in β‐Endorphin Processing
T2 - The Limitations of Slaughterhouse Material
AU - Smith, A. Ian
AU - Wallace, Catherine A.
AU - Clarke, Iain J.
AU - Funder, John W.
PY - 1989/1/1
Y1 - 1989/1/1
N2 - In the sheep, unlike many other species, a significant proportion (>25%) of immunoreactive β‐endorphin in the anterior pituitary is post‐translationally modified to opioid‐inactive, α‐N‐acetylated forms. In a study to determine the precise molecular nature of α‐N‐acetylated β‐endorphin immunoreactivity, we noted a striking difference in high‐performance liquid chromatography profiles of anterior pituitary extracts between sheep killed on the farm, and age‐, sex‐ and strain‐matched slaughterhouse animals. These altered patterns of a‐N‐acetylated β‐endorphin processing were reproduced in farm animals by chronic (≤ 4 days) treatment with the synthetic glucocorticoid dexamethasone; in contrast dexamethasone had no effect on a‐N‐acetylated β‐endorphin processing in hypothalamo‐pituitary disconnected sheep. These data suggest that (1) the change in processing is a stress response, mediated by prolonged glucocorticoid exposure, (2) this effect is central, rather than a direct effect on the pituitary, and (3) the relative abundance of various peptide sequences in slaughterhouse‐derived material may not reflect their abundance under more physiological conditions.
AB - In the sheep, unlike many other species, a significant proportion (>25%) of immunoreactive β‐endorphin in the anterior pituitary is post‐translationally modified to opioid‐inactive, α‐N‐acetylated forms. In a study to determine the precise molecular nature of α‐N‐acetylated β‐endorphin immunoreactivity, we noted a striking difference in high‐performance liquid chromatography profiles of anterior pituitary extracts between sheep killed on the farm, and age‐, sex‐ and strain‐matched slaughterhouse animals. These altered patterns of a‐N‐acetylated β‐endorphin processing were reproduced in farm animals by chronic (≤ 4 days) treatment with the synthetic glucocorticoid dexamethasone; in contrast dexamethasone had no effect on a‐N‐acetylated β‐endorphin processing in hypothalamo‐pituitary disconnected sheep. These data suggest that (1) the change in processing is a stress response, mediated by prolonged glucocorticoid exposure, (2) this effect is central, rather than a direct effect on the pituitary, and (3) the relative abundance of various peptide sequences in slaughterhouse‐derived material may not reflect their abundance under more physiological conditions.
KW - anterior pituitary
KW - glucocorticoids
KW - stress
KW - α‐N‐acetylation
KW - β‐endorphin
UR - http://www.scopus.com/inward/record.url?scp=0024330701&partnerID=8YFLogxK
U2 - 10.1111/j.1365-2826.1989.tb00129.x
DO - 10.1111/j.1365-2826.1989.tb00129.x
M3 - Article
AN - SCOPUS:0024330701
SN - 0953-8194
VL - 1
SP - 357
EP - 362
JO - Journal of Neuroendocrinology
JF - Journal of Neuroendocrinology
IS - 5
ER -