title: Calin--a platelet adhesion inhibitor from the saliva of the medicinal leech.
abstract: The saliva of the medicinal leech, Hirudo medicinalis, contains a potent, hitherto unsuspected, inhibitor of collagen-mediated platelet adhesion/aggregation. Calin, of molecular size approximately 65,000 (reduced), has a rapid (1-10 min) effect on collagen which is reflected in its ability to suppress collagen-induced platelet aggregation, as well as adhesion of platelets to collagen-coated microcarrier beads. It also causes flocculation of Type I collagen fibril suspensions. Calin is differentiated from leech collagenase in two ways: (1) by demonstrating, by SDS-PAGE analysis of the products of incubations of Calin with Type I collagen at 37 degrees C, that Calin binds to but does not cleave collagen; and (2) by showing that Calin cannot be purified using the methods used to isolate leech collagenase. Calin's rapid and unusual interaction with collagen makes it a prime candidate for one of the agents that are the causative factors of the prolonged bleeding phenomenon seen after leech bites.
authors.affiliation: Haematology Department, Morriston Hospital, Swansea, UK.
authors.forename: R
authors.initials: R
authors.lastname: Munro
authors.forename: C P
authors.initials: CP
authors.lastname: Jones
authors.forename: R T
authors.initials: RT
authors.lastname: Sawyer
mesh_terms: D000818:Animals; D003094:Collagen / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D007447:Invertebrate Hormones / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D007865:Leeches / Q000737:chemistry* / Q000502:physiology; D010973:Platelet Adhesiveness / Q000187:drug effects*; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D011485:Protein Binding; D011487:Protein Conformation / Q000187:drug effects; D012463:Saliva / Q000737:chemistry; D012471:Salivary Proteins and Peptides / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology
chemical_list: D007447:Invertebrate Hormones; D010975:Platelet Aggregation Inhibitors; D012471:Salivary Proteins and Peptides; C072490:calin; D003094:Collagen