Biomaterial Database

In-vitro platelet responses to arachidonic acid in the rat. 1995

B Rodriguez-Linares, and E Cano

Departamento de Farmacologia, Facultade de Farmacia, Universidade de Santiago de Compostela, Campus Sur, Galicia, Spain.

Using both the turbidimetric and the conductive methods to study aggregation of platelets, we found that arachidonic acid stimulated rat washed platelets in a dose-dependent manner (40 microM-0.5 mM). Although a high concentration of arachidonic acid (0.5 mM) produced an increase in light transmission both in the presence of 2 mM CaCl2 and EGTA (45.8 +/- 2.8 and 50.4 +/- 0.8% respectively) no changes in impedance were detected. Lysis caused by this concentration of arachidonic acid was very high at all the concentrations of calcium used (mean of 81.3%). In addition, the turbidimetric response induced by 0.5 mM arachidonic acid implied an initial decrease in light transmission but did not correlate with a real shape change. Forty micromolar arachidonic acid induced a calcium-dependent aggregation measured both by aggregometry and impedance. Morphology of aggregates induced by both concentrations was also studied. These results suggest that the optimal concentration for studying rat platelet activation by arachidonic acid is 40 microM; high concentrations (0.5 mM) cause aspecific effects not correlated to a physiological activation response.

UI	MeSH Term	Description	Entries
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D009391	Nephelometry and Turbidimetry	Chemical analysis based on the phenomenon whereby light, passing through a medium with dispersed particles of a different refractive index from that of the medium, is attenuated in intensity by scattering. In turbidimetry, the intensity of light transmitted through the medium, the unscattered light, is measured. In nephelometry, the intensity of the scattered light is measured, usually, but not necessarily, at right angles to the incident light beam.	Turbidimetry,Nephelometry,Turbidimetry and Nephelometry
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
D003078	Colchicine	A major alkaloid from Colchicum autumnale L. and found also in other Colchicum species. Its primary therapeutic use is in the treatment of gout, but it has been used also in the therapy of familial Mediterranean fever (PERIODIC DISEASE).	Colchicine, (+-)-Isomer,Colchicine, (R)-Isomer
D003571	Cytochalasin B	A cytotoxic member of the CYTOCHALASINS.	Phomin
D005340	Fibrinogen	Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.	Coagulation Factor I,Factor I,Blood Coagulation Factor I,gamma-Fibrinogen,Factor I, Coagulation,gamma Fibrinogen
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014750	Vincristine	An antitumor alkaloid isolated from VINCA ROSEA. (Merck, 11th ed.)	Leurocristine,Citomid,Farmistin,Oncovin,Oncovine,Onkocristin,Vincasar,Vincasar PFS,Vincristin Bristol,Vincristin medac,Vincristine Sulfate,Vincrisul,Vintec,cellcristin,PFS, Vincasar,Sulfate, Vincristine