Secretion of N-terminal pro-opiomelanocortin-derived peptides in response to acute haemorrhagic stress in conscious sheep.
To determine whether peptides derived from the N-terminus of the corticotropin/melanotropin/endorphin precursor, pro-opiomelanocortin, are released into blood in response to acute haemorrhagic stress, we examined the effect of haemorrhage on plasma concentrations of immunoreactive gamma 3-melanotropin, beta-endorphin and cortisol. Plasma concentrations of immunoreactive gamma 3-melanotropin (mean +/- SEM) increased within 30 min of haemorrhage from 71.1 +/- 10.4 to 106.8 +/- 6.3 fmol/mL (p less than 0.01) and plasma cortisol increased from 16.2 +/- 3.8 to 85.9 +/- 22.4 pmol/mL (p less than 0.025). The changes in plasma immunoreactive gamma 3-melanotropin and beta-endorphin were positively correlated (p less than 0.025). This study shows that peptides derived from the N-terminus of pro-opiomelanocortin are co-secreted with the C-terminal peptide beta-endorphin during acute haemorrhagic stress in sheep.
D000818:Animals; D004723:Endorphins / Q000097:blood; D006470:Hemorrhage / Q000097:blood; D006854:Hydrocortisone / Q000097:blood; D009074:Melanocyte-Stimulating Hormones / Q000097:blood; D011333:Pro-Opiomelanocortin / Q000097:blood / Q000378:metabolism*; D011863:Radioimmunoassay; D012756:Sheep; D013312:Stress, Physiological / Q000097:blood*; D001615:beta-Endorphin
D004723:Endorphins; D001615:beta-Endorphin; D011333:Pro-Opiomelanocortin; D009074:Melanocyte-Stimulating Hormones; D006854:Hydrocortisone