Boyd W H, Jichici D, Agro A, Rowell G, Gibbs B F
College of Biological Sciences, School of Human Biology, University of Guelph, Ontario, Canada.
Peptides. 1991 Jan-Feb;12(1):25-9. doi: 10.1016/0196-9781(91)90161-h.
Radioimmunoassay (RIA) detected the presence of beta-endorphin in the intraglandular colloid (IGC) of bovine pituitary intermediate lobe origin. The amount of beta-endorphin recovered in each of twelve samples ranged from 0.15 to 218.30 pmol/mg protein. A second group of assays [amino acid analysis, high performance liquid chromatography (HPLC) and mass spectral analysis] confirmed the RIA findings in another series of colloid samples. Approximately 75 pmol was collected from eight pooled glands. beta-Endorphin is an addition to the list of peptide hormones (e.g., methionine-enkephalin, adrenocorticotropin, arginine-vasopressin, alpha-melanocyte-stimulating hormone, beta-lipotropin and somatostatin) previously discovered in IGC by this laboratory.
