POMC in rhesus anterior pituitary and plasma: Evidence of N-acetylated [beta]-endorphin and [alpha]-MSH

Pro-opiomelanocortin (POMC) related peptides have been studied in rat tissue and plasma, but they have not been well characterized in the rhesus monkey. Since monkey pituitary may be more similar to the human pituitary than the rat, we have characterized POMC related peptides by immunocytochemical, multiple radioimmunoassays (RIA's) and molecular sieving chromatography.Immunocytochemical staining demonstrated N-acetylated- [beta]-endorphin (N-Ac- [beta]-End) and [alpha]-MSH in a few corticotrophs. RIA's of crude anterior pituitary extract and molecular sieving chromatography demonstrates that the major portion is [beta]-End sized with a significant proportion being N-acetylated and an [alpha]-MSH peak. Molecular sieving chromatography of extracted plasma demonstrated a similar pattern to that seen in the anterior pituitary. These data suggest that rhesus monkey processes POMC differently than rat or man.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25355/1/0000802.pd