Acute stress stimulates secretion of GHRH and somatostatin into hypophysial portal blood of conscious sheep.
The effects of acute stress on growth hormone (GH) secretion and the mechanisms involved in its changes have been investigated in sheep. An acute isolation-restraint stress induced a rapid and significant increase in jugular GH levels in 12 out of 14 rams. GH-releasing hormone (GHRH) and somatostatin secretion during the same stress were studied in 5 animals prepared for hypophysial portal blood collection. A 3.5-fold increase in portal GHRH levels was observed concomitantly with a slight elevation in portal somatostatin. Portal corticotropin-releasing hormone (CRH) and jugular cortisol plasma levels increased during the same stress. Our data suggest that an isolation-restraint stress stimulates GH secretion in the sheep and that GHRH may be responsible for GH response.
Cataldi
M
M
INSERUM U 297, Intitut Fédératif Jean Roche, Faculté de Médicine Nord, Marseille, France.
Magnan
E
E
Guillaume
V
V
Dutour
A
A
Sauze
N
N
Mazzocchi
L
L
Conte-Devolx
B
B
Oliver
C
C
D000704:Analysis of Variance; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000097:blood; D013007:Growth Hormone-Releasing Hormone / Q000097:blood / Q000378:metabolism*; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D010902:Pituitary Gland / Q000098:blood supply / Q000378:metabolism*; D012149:Restraint, Physical; D012756:Sheep; D012934:Social Isolation; D013004:Somatostatin / Q000097:blood / Q000378:metabolism*; D013315:Stress, Psychological / Q000503:physiopathology*; D013997:Time Factors
D013004:Somatostatin; D003346:Corticotropin-Releasing Hormone; D013007:Growth Hormone-Releasing Hormone; D006854:Hydrocortisone