Biomaterial Database

Competitive inhibition of tritium-labeled platelet-activating factor binding to rabbit platelet membranes by amiloride and amiloride analogs. 1989

S B Hwang

Department of Biochemical Regulation, Merck Sharp & Dohme Research Laboratories, Rahway, New Jersey 07065-0900.

Amiloride and its structural analogs, ethylisopropyl amiloride, benzamil, and dichlorobenzamil, inhibit both the specific [3H]C18-PAF binding to rabbit platelet membranes and PAF-induced aggregation of gel-filtered rabbit platelets. Detailed analysis of binding inhibitions demonstrate that ethylisopropyl amiloride is a competitive inhibitor with an equilibrium dissociation constant (KB) of 23 microM. The concentration of amiloride and its analogs needed to inhibit the PAF-induced aggregation is high and there exists no correlation between their inhibitory activities of platelet aggregation and those of Na+/H+ antiporter. However, the inhibitory effects on the PAF-induced aggregation are parallel to those on the specific [3H]C18-PAF binding. The inhibitory effects of amiloride and its analogs on the activation of platelets are at the PAF-receptor binding step, rather than at the Na+/H+ antiporter.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010972	Platelet Activating Factor	A phospholipid derivative formed by PLATELETS; BASOPHILS; NEUTROPHILS; MONOCYTES; and MACROPHAGES. It is a potent platelet aggregating agent and inducer of systemic anaphylactic symptoms, including HYPOTENSION; THROMBOCYTOPENIA; NEUTROPENIA; and BRONCHOCONSTRICTION.	AGEPC,Acetyl Glyceryl Ether Phosphorylcholine,PAF-Acether,Phosphorylcholine, Acetyl Glyceryl Ether,1-Alkyl-2-acetyl-sn-glycerophosphocholine,Platelet Aggregating Factor,Platelet Aggregation Enhancing Factor,Platelet-Activating Substance,Thrombocyte Aggregating Activity,1 Alkyl 2 acetyl sn glycerophosphocholine,Aggregating Factor, Platelet,Factor, Platelet Activating,PAF Acether,Platelet Activating Substance
D010974	Platelet Aggregation	The attachment of PLATELETS to one another. This clumping together can be induced by a number of agents (e.g., THROMBIN; COLLAGEN) and is part of the mechanism leading to the formation of a THROMBUS.	Aggregation, Platelet
D010975	Platelet Aggregation Inhibitors	Drugs or agents which antagonize or impair any mechanism leading to blood platelet aggregation, whether during the phases of activation and shape change or following the dense-granule release reaction and stimulation of the prostaglandin-thromboxane system.	Antiaggregants, Platelet,Antiplatelet Agent,Antiplatelet Agents,Antiplatelet Drug,Blood Platelet Aggregation Inhibitor,Blood Platelet Antagonist,Blood Platelet Antiaggregant,PAR-1 Antagonists,Platelet Aggregation Inhibitor,Platelet Antagonist,Platelet Antagonists,Platelet Antiaggregant,Platelet Antiaggregants,Platelet Inhibitor,Protease-Activated Receptor-1 Antagonists,Antiplatelet Drugs,Blood Platelet Aggregation Inhibitors,Blood Platelet Antagonists,Blood Platelet Antiaggregants,Platelet Inhibitors,Agent, Antiplatelet,Aggregation Inhibitor, Platelet,Antagonist, Blood Platelet,Antagonist, Platelet,Antiaggregant, Blood Platelet,Antiaggregant, Platelet,Drug, Antiplatelet,Inhibitor, Platelet,Inhibitor, Platelet Aggregation,PAR 1 Antagonists,Platelet Antagonist, Blood,Platelet Antiaggregant, Blood,Protease Activated Receptor 1 Antagonists
D010980	Platelet Membrane Glycoproteins	Surface glycoproteins on platelets which have a key role in hemostasis and thrombosis such as platelet adhesion and aggregation. Many of these are receptors.	PM-GP,Platelet Glycoprotein,Platelet Membrane Glycoprotein,PM-GPs,Platelet Glycoproteins,Glycoprotein, Platelet,Glycoprotein, Platelet Membrane,Glycoproteins, Platelet,Glycoproteins, Platelet Membrane,Membrane Glycoprotein, Platelet,Membrane Glycoproteins, Platelet,PM GP
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D001792	Blood Platelets	Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.	Platelets,Thrombocytes,Blood Platelet,Platelet,Platelet, Blood,Platelets, Blood,Thrombocyte
D002352	Carrier Proteins	Proteins that bind or transport specific substances in the blood, within the cell, or across cell membranes.	Binding Proteins,Carrier Protein,Transport Protein,Transport Proteins,Binding Protein,Protein, Carrier,Proteins, Carrier
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes