Beta-endorphin is present in active and inactive forms in rat gastric antrum.
Lipotropin, beta-endorphin and a series of peptides related to beta-endorphin were extracted from rat antrum and resolved by gel filtration, ion exchange chromatography and high pressure liquid chromatography; the concentrations of the peptides were determined by radioimmunoassay. The major peptide with beta-endorphin immunoreactivity present in the antrum was lipotropin but it was accompanied by substantial quantities of beta-endorphin in its biologically active form; in addition there were minor quantities of a number of inactive beta-endorphin related peptides. The experiments demonstrate that in rat antrum gastrin can be accompanied by both active and inactive forms of beta-endorphin. The implications of post-translational processing mechanisms common to gastrin and beta-endorphin are discussed.
D000818:Animals; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D004723:Endorphins / Q000032:analysis*; D005755:Gastrins / Q000032:analysis; D011706:Pyloric Antrum / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains; D001615:beta-Endorphin; D008083:beta-Lipotropin / Q000032:analysis
D004723:Endorphins; D005755:Gastrins; D001615:beta-Endorphin; D008083:beta-Lipotropin