Amphibian Bombesin-Like Peptides

ABSTRACT The bombesin-like peptides were originally isolated from frog skin, but the discovery of extensive effects in mammals led to the search for and discovery of mammalian homologs. In frogs, four groupings of bombesin-like peptides have been described: the bombesins, the ranatensins, and the phyllolitorins, which are present in skin, and gastrin-releasing peptide (GRP), which is not present in skin. In mammals, two bombesin-like peptides have been described: gastrin-releasing peptide (GRP) and neuromedin B (NMB). Whether mammals have additional bombesin-like peptides related to the frog skin bombesin-like peptides remains to be determined. The receptors for amphibian bombesin-like peptides are 7-transmembrane G-protein coupled receptors linked to generation of IP3. Despite investigation, the exact role of bombesin-like peptides in frog skin remains unknown.