Isolation and primary structure of novel neurointermediate pituitary peptides derived from the C-terminal of the rat vasopressin-neurophysin precursor (propressophysin)

Four novel peptides were isolated from rat neurointermediate lobes by gel filtration and high-pressure liquid chromatography. Analyses of amino acid composition and sequence showed that all four peptides were derived from the C-terminal portion of propressophysin (CPP); they were identified as the glycopeptides CPP 1-19, CPP 1-20, CPP 22-37 and CPP 22-39. Processing of CPP 1-39 could thus produce the four isolated peptides by specific post-Arg or post-Leu cleavages.