1. Pharmacology of the Thromboxane Receptor Antagonist and Thromboxane Synthase Inhibitor BM-531
- Author
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P. Neven, Jacques Delarge, P. Benoit, Bernard Masereel, J. L. David, Philippe Kolh, Jean-Michel Dogné, X. De Leval, Stéphanie Rolin, and Jacques Damas
- Subjects
Blood Platelets ,Agonist ,medicine.medical_specialty ,medicine.drug_class ,Thromboxane ,Receptors, Thromboxane ,Prostacyclin ,Pharmacology ,Radioligand Assay ,Thromboxane A2 ,chemistry.chemical_compound ,Internal medicine ,medicine ,Animals ,Humans ,Platelet ,Gastric Fundus ,Enzyme Inhibitors ,Receptor ,Sulfonamides ,biology ,Antagonist ,Muscle, Smooth ,Torsemide ,Diuresis ,Sulfonylurea Compounds ,Endocrinology ,chemistry ,biology.protein ,Arachidonic acid ,Thromboxane-A Synthase ,Thromboxane-A synthase ,Cardiology and Cardiovascular Medicine ,Platelet Aggregation Inhibitors ,Muscle Contraction ,medicine.drug - Abstract
BM-531 (N-tert-butyl-N'-[(2-cyclohexylamino-5-nitrobenzene)sulfonyl]urea), a torasemide derivative, is a novel noncarboxylic thromboxane receptor antagonist and thromboxane synthase inhibitor. Indeed, its affinity for human washed platelet TXA2 receptors labeled with [3H]SQ-29548 (IC50 = 0.0078 microM) is higher than sulotroban (IC50 = 0.93 microM) and SQ-29548 (IC50 = 0.021 microM). Moreover, BM-531 is characterized by a potent antiaggregatory property. Indeed, on one hand, in human citrated platelet-rich plasma BM-531 prevents platelet aggregation induced by arachidonic acid (600 microM) (ED100 = 0.125 microM), U-46619, a stable TXA2 agonist (1 microM) (ED50 = 0.482 microM) or collagen (1 microgram/mL) (percentage of inhibition: 42.9% at 10 microM) and inhibits the second wave of ADP (2 microM)-induced aggregation. On the other hand, when BM-531 is incubated in whole blood from healthy donors, the closure time measured by the recently developed platelet function analyser (PFA-100) is significantly prolonged. In addition, at the concentrations of 10 and 1 microM, BM-531 totally prevents the production of TXB2 by human platelets activated by arachidonic acid. Finally, at 10 microM, BM-531 significantly prevents rat fundus contractions induced by U-46619 but not by prostacyclin. These results suggest that BM-531, which is devoid of the diuretic property of torasemide, can be regarded as a promising antiplatelet agent.
- Published
- 2006