Biomaterial Database

Measurement of platelet ionized calcium. 1985

E W Salzman, and P Johnson, and J A Ware

We measured ionized cytoplasmic calcium in human blood platelets by two techniques: one based on the fluorescence of intracellular Quin 2 and the other based on the luminescence of the calcium sensitive photoprotein, aequorin. Platelet activation (shape change, aggregation, secretion) induced by thrombin, ADP, epinephrine, collagen, A23187, or phorbol ester was invariably preceded or accompanied by a rise in platelet free calcium indicated by aequorin, but in some cases Quin 2 failed to detect the elevation of calcium concentration. Aequorin appears to be sensitive to localized changes in cytoplasmic calcium levels, while Quin 2 reflects average or diffuse calcium values. Failure of Quin 2 to indicate a rise in free calcium levels in association with a platelet activity does not establish the process as "calcium independent".

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008163	Luminescent Measurements	Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.	Bioluminescence Measurements,Bioluminescent Assays,Bioluminescent Measurements,Chemiluminescence Measurements,Chemiluminescent Assays,Chemiluminescent Measurements,Chemoluminescence Measurements,Luminescence Measurements,Luminescent Assays,Luminescent Techniques,Phosphorescence Measurements,Phosphorescent Assays,Phosphorescent Measurements,Assay, Bioluminescent,Assay, Chemiluminescent,Assay, Luminescent,Assay, Phosphorescent,Assays, Bioluminescent,Assays, Chemiluminescent,Assays, Luminescent,Assays, Phosphorescent,Bioluminescence Measurement,Bioluminescent Assay,Bioluminescent Measurement,Chemiluminescence Measurement,Chemiluminescent Assay,Chemiluminescent Measurement,Chemoluminescence Measurement,Luminescence Measurement,Luminescent Assay,Luminescent Measurement,Luminescent Technique,Measurement, Bioluminescence,Measurement, Bioluminescent,Measurement, Chemiluminescence,Measurement, Chemiluminescent,Measurement, Chemoluminescence,Measurement, Luminescence,Measurement, Luminescent,Measurement, Phosphorescence,Measurement, Phosphorescent,Measurements, Bioluminescence,Measurements, Bioluminescent,Measurements, Chemiluminescence,Measurements, Chemiluminescent,Measurements, Chemoluminescence,Measurements, Luminescence,Measurements, Luminescent,Measurements, Phosphorescence,Measurements, Phosphorescent,Phosphorescence Measurement,Phosphorescent Assay,Phosphorescent Measurement,Technique, Luminescent,Techniques, Luminescent
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
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
D005456	Fluorescent Dyes	Chemicals that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.	Flourescent Agent,Fluorescent Dye,Fluorescent Probe,Fluorescent Probes,Fluorochrome,Fluorochromes,Fluorogenic Substrates,Fluorescence Agents,Fluorescent Agents,Fluorogenic Substrate,Agents, Fluorescence,Agents, Fluorescent,Dyes, Fluorescent,Probes, Fluorescent,Substrates, Fluorogenic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000242	Cyclic AMP	An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.	Adenosine Cyclic 3',5'-Monophosphate,Adenosine Cyclic 3,5 Monophosphate,Adenosine Cyclic Monophosphate,Adenosine Cyclic-3',5'-Monophosphate,Cyclic AMP, (R)-Isomer,Cyclic AMP, Disodium Salt,Cyclic AMP, Monoammonium Salt,Cyclic AMP, Monopotassium Salt,Cyclic AMP, Monosodium Salt,Cyclic AMP, Sodium Salt,3',5'-Monophosphate, Adenosine Cyclic,AMP, Cyclic,Adenosine Cyclic 3',5' Monophosphate,Cyclic 3',5'-Monophosphate, Adenosine,Cyclic Monophosphate, Adenosine,Cyclic-3',5'-Monophosphate, Adenosine,Monophosphate, Adenosine Cyclic
D000331	Aequorin	A photoprotein isolated from the bioluminescent jellyfish Aequorea. It emits visible light by an intramolecular reaction when a trace amount of calcium ion is added. The light-emitting moiety in the bioluminescence reaction is believed to be 2-amino-3-benzyl-5-(p-hydroxyphenyl)pyrazine (AF-350).	Aequorine
D000634	Aminoquinolines	Quinolines substituted in any position by one or more amino groups.