title: Evidence for the dependence of arterial haemostasis on ADP.
abstract: The possible involvement of adenosine diphosphate (ADP) in haemostatic platelet aggregation was investigated by determining the duration of primary haemorrhage as standardized bleeding times from punctures of small mesenteric arteries in anaesthetized rats. The bleeding times were highly significantly increased by infusing into the mesenteric arterial blood flowing towards the punctures either the nucleotide-dephosphorylating enzyme apyrase or the ADP-receptor antagonists ATP, adenosine 5'-(beta,gamma-methylene)triphosphonate (AMP-PCP) or 2-methylthioadenosine 5'-(beta,gamma-methylene)triphosphonate (2-MeS-AMP-PCP). The increases in bleeding times could not be accounted for by local vasodilator effects of the agents. It is concluded that the presence of ADP through local release and/or formation at sites of vascular injury contributes significantly to haemostasis, presumably by accelerating platelet aggregation.
authors.affiliation: Department of Pharmacology, King's College London, U.K.
authors.forename: M O
authors.initials: MO
authors.lastname: McClure
authors.forename: A
authors.initials: A
authors.lastname: Kakkar
authors.forename: N J
authors.initials: NJ
authors.lastname: Cusack
authors.forename: G V
authors.initials: GV
authors.lastname: Born
mesh_terms: D000227:Adenine Nucleotides / Q000494:pharmacology; D000244:Adenosine Diphosphate / Q000037:antagonists & inhibitors / Q000502:physiology*; D000818:Animals; D001081:Apyrase / Q000494:pharmacology*; D006470:Hemorrhage / Q000503:physiopathology*; D006487:Hemostasis / Q000187:drug effects*; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000503:physiopathology; D008642:Mesenteric Veins / Q000187:drug effects / Q000503:physiopathology; D051379:Mice; D010744:Phosphoric Monoester Hydrolases / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011983:Receptors, Purinergic / Q000187:drug effects / Q000502:physiology; D012016:Reference Values
chemical_list: D000227:Adenine Nucleotides; D011983:Receptors, Purinergic; D000244:Adenosine Diphosphate; D010744:Phosphoric Monoester Hydrolases; D001081:Apyrase