title: Comparative histochemistry as a springboard for the discovery of biogenic amines and active peptides in molluscan tissues and amphibian skin.
abstract: Histochemistry has been the springboard for the identification in molluscan tissues (hypobranchial body and salivary glands) and amphibian skin of a number of biogenic amines, choline esters and active peptides. Among the biogenic amines 5-HT and related indolealkylamines, octopamine, tyramine and several histamines are to be listed; among the choline esters murexine, dihydromurexine, senecioylcholine and acryloylcholine; among the peptides an array of compounds belonging to at least ten different peptide families. 5-HT, octopamine, tyramine and histamine are present, together with representatives of some peptide families in the posterior salivary glands of octopods, the hypobranchial body of prosobranchiate molluscs and the amphibian skin. This points to the possible occurrence in the above structures of cells belonging to the Pearse's APUD series, intended in its broadest sense. Immunocytochemical studies and even ultrastructural studies on amine and peptide storing cells in molluscan tissues and amphibian skin are virtually lacking. This is certainly a gap that deserves to be filled, considering that these studies may help in elucidating problems of general relevance in invertebrates and vertebrates.
mesh_terms: D029845:Amphibian Proteins; D000663:Amphibians / Q000378:metabolism*; D000818:Animals; D001679:Biogenic Amines / Q000032:analysis*; D055598:Chemical Phenomena; D002621:Chemistry; D005880:Gills / Q000032:analysis; D006651:Histocytochemistry; D049831:Octopodiformes / Q000032:analysis; D009842:Oligopeptides / Q000032:analysis; D018847:Opioid Peptides; D036361:Peptide Hormones; D010455:Peptides / Q000032:analysis*; D012469:Salivary Glands / Q000032:analysis; D012867:Skin / Q000032:analysis
chemical_list: D029845:Amphibian Proteins; D001679:Biogenic Amines; D009842:Oligopeptides; D018847:Opioid Peptides; D036361:Peptide Hormones; D010455:Peptides; C030058:dermorphin; C025727:sauvagine; C030059:dermorphin, 4-Hyp(6)-