title: Prevention of thrombosis and rethrombosis and enhancement of the thrombolytic actions of recombinant tissue-type plasminogen activator in the canine heart by DMP728, a glycoprotein IIb/IIIa antagonist.
abstract: 1. We studied DMP728, a non-peptide glycoprotein (GP) IIb/IIIa receptor antagonist, for prevention of coronary artery thrombosis or rethrombosis in a chronic canine model subjected to arterial injury. 2. In protocol I, DMP728 (1.0 mg kg-1, i.v., n = 8) or saline (n = 8) was administered and a 150 microA anodal current was applied to the intimal surface of the left circumflex coronary artery (LCX). Dogs were monitored for 6 h and again on each of 5 subsequent days. 3. Ex vivo platelet aggregation was inhibited but returned to baseline 1 day after drug administration. Thrombus weight was reduced (saline, 20.7 +/- 5.0 mg; DMP728 1.7 +/- 0.4 mg; P < 0.05), as was infarct size [saline, 27.5 +/- 4.3; DMP728, 1.6 +/- 0.7 (per cent left ventricle); P < 0.05]. All control animals died by day 3, while all but one of the treated dogs survived the entire protocol (P < 0.05). 4. In protocol II, an LCX thrombus was induced and thrombolytic therapy was initiated 30 min later. DMP728 (1.0 mg kg-1, i.v., n = 8) or saline (n = 8) was administered 5 min after recombinant tissue-type plasminogen activator infusion had begun. The incidence of reocclusion was reduced by DMP728 (saline, 4/8; DMP728, 1/8). One day after thrombolysis, 7/8 DMP728-treated animals were alive compared with 1/8 in the control group (P = 0.01). 5. DMP728 inhibited ex vivo platelet aggregation, prevented primary and secondary occlusive thrombus formation, reduced thrombus weight and infarct size and increased survival in a chronic canine model of coronary artery thrombus formation. DMP728 is an effective anti-platelet intervention when used as the singular adjunctive agent in association with thrombolytic therapy.
authors.affiliation: Department of Pharmacology, University of Michigan Medical School, Ann Arbor 48109-0632.
authors.forename: B R
authors.initials: BR
authors.lastname: Lucchessi
authors.forename: W E
authors.initials: WE
authors.lastname: Rote
authors.forename: E M
authors.initials: EM
authors.lastname: Driscoll
authors.forename: D X
authors.initials: DX
authors.lastname: Mu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003331:Coronary Vessels / Q000502:physiology; D004285:Dogs; D005343:Fibrinolytic Agents / Q000494:pharmacology*; D008297:Male; D008698:Mesylates / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009203:Myocardial Infarction / Q000097:blood / Q000473:pathology; D010456:Peptides, Cyclic / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D010980:Platelet Membrane Glycoproteins / Q000037:antagonists & inhibitors*; D011994:Recombinant Proteins / Q000494:pharmacology; D012008:Recurrence; D013927:Thrombosis / Q000097:blood / Q000473:pathology / Q000517:prevention & control*; D010959:Tissue Plasminogen Activator / Q000494:pharmacology*
chemical_list: D005343:Fibrinolytic Agents; D008698:Mesylates; D010456:Peptides, Cyclic; D010975:Platelet Aggregation Inhibitors; D010980:Platelet Membrane Glycoproteins; D011994:Recombinant Proteins; C085286:DMP 728; D010959:Tissue Plasminogen Activator