Biomaterial Database

Prehispanolone, a novel platelet activating factor receptor antagonist from Leonurus heterophyllus. 1991

C M Lee, and L M Jiang, and H S Shang, and P M Hon, and Y He, and H N Wong

Department of Biochemistry, Chinese Medicinal Material Research Centre, Shatin, N.T., Hong Kong.

1. Using an in vitro radioligand binding assay for the platelet activating factor (PAF) receptor, we have identified a novel, specific PAF antagonist, prehispanolone, from a Chinese medicinal herb Leonurus heterophyllus. 2. The presence of sodium ions inhibited specific [3H]-PAF binding to rabbit platelet membrane with an IC50 of 5.2 mM, decreased the inhibitory potency of PAF but increased the inhibitory potency of prehispanolone. 3. Prehispanolone and several of its derivatives inhibited the binding of [3H]-PAF to rabbit platelets with potencies closely resembling that of inhibition of PAF-induced aggregation. 4. The integrity of the tetrahydrofuran ring of prehispanolone is critical for its interaction with the PAF receptor. 5. By hydrogenating the dihydrofuran ring and replacing the keto group of prehispanolone with a hydroxyl group, we obtained a compound, LC5507, that is more stable and more active than prehispanolone as a PAF receptor antagonist.

UI	MeSH Term	Description	Entries
D007783	Lactones	Cyclic esters of hydroxy carboxylic acids, containing a 1-oxacycloalkan-2-one structure. Large cyclic lactones of over a dozen atoms are MACROLIDES.	Lactone
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
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
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
D011869	Radioligand Assay	Quantitative determination of receptor (binding) proteins in body fluids or tissue using radioactively labeled binding reagents (e.g., antibodies, intracellular receptors, plasma binders).	Protein-Binding Radioassay,Radioreceptor Assay,Assay, Radioligand,Assay, Radioreceptor,Assays, Radioligand,Assays, Radioreceptor,Protein Binding Radioassay,Protein-Binding Radioassays,Radioassay, Protein-Binding,Radioassays, Protein-Binding,Radioligand Assays,Radioreceptor Assays
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
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