title: Physalaemin: an amphibian tachykinin in human lung small-cell carcinoma.
abstract: Immunoreactivity to the amphibian peptide physalaemin was characterized from extracts of a human lung small-cell carcinoma by immunological, chemical, and pharmacological means. Tumor-related peptide cross-reacted with three antiserums to physalaemin to yield 1.1 to 1.6 nanomoles per gram of tissue. Physalaemin and tumor peptide had similar retention times on high-performance liquid chromatography after chemical and enzymic modifications that included pH changes, oxone oxidation, use of a hydrophilic ion-pairing reagent, and digestion with trypsin and pyroglutamate aminopeptidase. Both physalaemin and the tumor peptide produced a contractile response of isolated guinea pig ileum at threshold concentrations of approximately 100 to 150 picograms per milliliter. These data suggest that small-cell carcinoma of the lung contains a physalaemin-like peptide that has structural and biological homology to its amphibian counterpart.
mesh_terms: D018288:Carcinoma, Small Cell / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions; D006801:Humans; D007106:Immune Sera; D007705:Kinins / Q000378:metabolism*; D008175:Lung Neoplasms / Q000378:metabolism*; D010084:Oxidation-Reduction; D010455:Peptides / Q000378:metabolism*; D010803:Physalaemin / Q000378:metabolism*; D015320:Tachykinins
chemical_list: D007106:Immune Sera; D007705:Kinins; D010455:Peptides; D015320:Tachykinins; D010803:Physalaemin