Biomaterial Database

The platelet strip. II. Pharmacomechanical coupling in thrombin-activated human platelets. 1985

L Salganicoff, and R W Sevy

A model of contracted, irreversibly aggregated thrombin-activated human platelets relaxes when treated with ethyleneglycol-bis(beta-aminoethylether-N,N'-tetraacetic acid (EGTA) in the presence of Mg2+. Inhibition of the cyclooxygenase or blockade of the thromboxane A2 receptor decreases the tension partially, but EGTA treatment is needed for full relaxation. After a stable relaxation has been achieved (3-4 h), Ca2+ addition in a cumulative manner does not reinduce contraction. Whether in the absence or presence of external Ca2+, the relaxed preparation contracts when stimulated with ADP, epinephrine, thromboxane A2 or its analogues, or thrombin. At supramaximal doses, each of the agonists activates only a partial amount of the total tension capable of being generated. Addition of an agonist of a different class to the partially contracted preparation further increases its force. The contractile responses are reversible on washout, with kinetics dependent on the class of agonist and time of contact with the preparation. The contraction induced by the prolonged simultaneous stimulation with ADP, arachidonate, and thrombin reverts very slowly on washout of the agonists and for all practical purposes reproduces the initial state of irreversible platelet contraction.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
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
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
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002463	Cell Membrane Permeability	A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.	Permeability, Cell Membrane
D004533	Egtazic Acid	A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.	EGTA,Ethylene Glycol Tetraacetic Acid,EGATA,Egtazic Acid Disodium Salt,Egtazic Acid Potassium Salt,Egtazic Acid Sodium Salt,Ethylene Glycol Bis(2-aminoethyl ether)tetraacetic Acid,Ethylenebis(oxyethylenenitrile)tetraacetic Acid,GEDTA,Glycoletherdiamine-N,N,N',N'-tetraacetic Acid,Magnesium-EGTA,Tetrasodium EGTA,Acid, Egtazic,EGTA, Tetrasodium,Magnesium EGTA
D004837	Epinephrine	The active sympathomimetic hormone from the ADRENAL MEDULLA. It stimulates both the alpha- and beta- adrenergic systems, causes systemic VASOCONSTRICTION and gastrointestinal relaxation, stimulates the HEART, and dilates BRONCHI and cerebral vessels. It is used in ASTHMA and CARDIAC FAILURE and to delay absorption of local ANESTHETICS.	Adrenaline,4-(1-Hydroxy-2-(methylamino)ethyl)-1,2-benzenediol,Adrenaline Acid Tartrate,Adrenaline Bitartrate,Adrenaline Hydrochloride,Epifrin,Epinephrine Acetate,Epinephrine Bitartrate,Epinephrine Hydrochloride,Epinephrine Hydrogen Tartrate,Epitrate,Lyophrin,Medihaler-Epi,Acetate, Epinephrine
D005229	Fatty Acids, Monounsaturated	Fatty acids which are unsaturated in only one position.	Monounsaturated Fatty Acid,Acid, Monounsaturated Fatty,Acids, Monounsaturated Fatty,Fatty Acid, Monounsaturated,Monounsaturated Fatty Acids
D005231	Fatty Acids, Unsaturated	FATTY ACIDS in which the carbon chain contains one or more double or triple carbon-carbon bonds.	Fatty Acids, Polyunsaturated,Polyunsaturated Fatty Acid,Unsaturated Fatty Acid,Polyunsaturated Fatty Acids,Acid, Polyunsaturated Fatty,Acid, Unsaturated Fatty,Acids, Polyunsaturated Fatty,Acids, Unsaturated Fatty,Fatty Acid, Polyunsaturated,Fatty Acid, Unsaturated,Unsaturated Fatty Acids