Biomaterial Database

Transport and metabolism of adenosine in human blood platelets. 1976

J J Sixma, and J P Lips, and A M Trieschnigg, and H Holmsen

The uptake and metabolism of [14C]- or E[3H] adenosine have been studied in suspensions of washed platelets and in platelet rich plasma. The appearance of radioactivity in the platelets and the formation of radioactive adenosine metabolites have been used to determine the uptake. Adenosine is transported into human blood platelets by two different systems: a low Km system (9.8 muM) which is competitively inhibited by papaverine, and a high Km system (9.4 mM) which is competitively inhibited by adenine. Adenosine transported via the low Km system is probably directly incorporated into adenine nucleotides, while adenosine transported through the high Km system arrives unchanged inside the platelet and is then converted into inosine and hypoxanthine or incorporated into adenine nucleotides.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010042	Ouabain	A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.	Acocantherin,G-Strophanthin,Acolongifloroside K,G Strophanthin
D010208	Papaverine	An alkaloid found in opium but not closely related to the other opium alkaloids in its structure or pharmacological actions. It is a direct-acting smooth muscle relaxant used in the treatment of impotence and as a vasodilator, especially for cerebral vasodilation. The mechanism of its pharmacological actions is not clear, but it apparently can inhibit phosphodiesterases and it may have direct actions on calcium channels.	Cerespan,Papaverine Hydrochloride,Pavabid,Pavatym,Hydrochloride, Papaverine
D010695	Phlorhizin		Phloridzin,Phlorizin
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
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
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000225	Adenine	A purine base and a fundamental unit of ADENINE NUCLEOTIDES.	Vitamin B 4,4, Vitamin B,B 4, Vitamin
D000241	Adenosine	A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.	Adenocard,Adenoscan
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding