Biomaterial Database

Echinocytosis and microvesiculation of human erythrocytes induced by insertion of merocyanine 540 into the outer membrane leaflet. 1989

D Allan, and C Hagelberg, and K J Kallen, and C W Haest

Department of Physiology, University College and Middlesex School of Medicine, London, U.K.

Echinocytosis and release of microvesicles from human erythrocytes treated with the impermeant fluorescent dye merocyanine 540 (MC540) has been correlated with the extent of dye binding to intact cells and ghosts. At 20 degrees C binding appeared to saturate at about 9.3.10(6) molecules per cell (3.6 mol/100 mol phospholipid), equivalent to an expansion of the outer leaflet lipid area of about 2.7%. Stage 3 echinocytes were formed upon binding of (3-4).10(6) molecules of MC540/cell (about 1.3 mol/100 mol phospholipid), equivalent to an expansion of the outer leaflet lipid area of about 1.0%. Negligible release of microvesicles was observed with MC540 at 20 degrees C. Binding of MC540 to permeable ghosts was approximately twice that to cells suggesting that there was no selective binding to the unsaturated (more fluid) phospholipids which are concentrated in the inner lipid leaflet of the membrane. At 37 degrees C apparent maximal binding of MC540 was about 3.2 mol/100 mol phospholipid and correlated with the maximal release of microvesicles from the cells as measured by release of phospholipid and acetylcholinesterase. These results are discussed in relation to the bilayer couple hypothesis of Sheetz and Singer (Proc. Natl. Acad. Sci. USA 71 (1974) 4457-4461).

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008563	Membrane Lipids	Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.	Cell Membrane Lipid,Cell Membrane Lipids,Membrane Lipid,Lipid, Cell Membrane,Lipid, Membrane,Lipids, Cell Membrane,Lipids, Membrane,Membrane Lipid, Cell,Membrane Lipids, Cell
D010743	Phospholipids	Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.	Phosphatides,Phospholipid
D011744	Pyrimidinones	Heterocyclic compounds known as 2-pyrimidones (or 2-hydroxypyrimidines) and 4-pyrimidones (or 4-hydroxypyrimidines) with the general formula C4H4N2O.	Pyrimidinone,Pyrimidone,Pyrimidones
D004910	Erythrocyte Membrane	The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.	Erythrocyte Ghost,Red Cell Cytoskeleton,Red Cell Ghost,Erythrocyte Cytoskeleton,Cytoskeleton, Erythrocyte,Cytoskeleton, Red Cell,Erythrocyte Cytoskeletons,Erythrocyte Ghosts,Erythrocyte Membranes,Ghost, Erythrocyte,Ghost, Red Cell,Membrane, Erythrocyte,Red Cell Cytoskeletons,Red Cell Ghosts
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
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