PRODUCTION AND CHARACTERIZATION OF SITE-DIRECTED ANTIBODIES AGAINST DERMORPHIN AND DERMORPHIN-RELATED PEPTIDES

To detect and purify endogenous dermorphin-like molecules in mammalian tissues, an immunological approach was developed. Site-directed antib odies against synthetic dermorphin and related dermorphin peptides wer e produced. The immunogenic forms of dermorphin were selected to obtai n antibodies recognizing different epitopes overlapping the whole derm orphin molecule. One of them specifically recognized the crucial ''opi oid message'' (the N-terminal part of the molecule), which is required for a ligand to exert its full opioid activity. The validity of our i mmunological approach was analyzed by studying the dermorphin-related peptide distribution in Phyllomedusa sauvagei skin. The finding that t etrapeptide Y-A-G-F-OH was prevent in Phyllomedusa sauvagei extracts s uggested that either the Tyr(5)-Pro(6) peptidic bond may be relatively unstable or endogenous proteolytic enzymes present in Phyllomedusa sk in may inactivate this peptidic bond.