Biomaterial Database

The influence of valinomycin induced membrane potential on erythrocyte shape. 1991

R Glaser, and C Gengnagel, and J Donath

Institute of Biophysics, Humboldt University, Berlin.

In addition to previous observations indicating that membrane potential changes generated by various Donnan- and Nernst-potentials lead to erythrocyte shape transformations, we show in this paper that diffusion potential change, induced by valinomycin, governs erythrocyte shape transformations. In low KCl-medium valinomycin, transferring the positive Nernst-potential into a negative diffusion potential, transforms stomatocytes into echinocytes. Using modified erythrocytes with a reversed K/Na ratio, even positive diffusion potentials can be induced by valinomycin. In these cases, stomatocytes can be generated by valinomycin. It is shown that, additionally, valinomycin in large concentrations is itself stomatocytogenic, and that the fluorescent dye diS-C3-(5) also induces stomatocytes. This, however, is a side effect which does not contradict the potential dependence of shape transformation. Using non washed erythrocytes, resuspended in plasma, valinomycin, inducing negative diffusion potential, transforms most erythrocytes to echinocytes despite the stomatocytogenic effect of albumin.

UI	MeSH Term	Description	Entries
D008564	Membrane Potentials	The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).	Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D002232	Carbocyanines	Compounds that contain three methine groups. They are frequently used as cationic dyes used for differential staining of biological materials.	Carbocyanine
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
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000418	Albumins	Water-soluble proteins found in egg whites, blood, lymph, and other tissues and fluids. They coagulate upon heating.	Albumin
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23
D014634	Valinomycin	A cyclododecadepsipeptide ionophore antibiotic produced by Streptomyces fulvissimus and related to the enniatins. It is composed of 3 moles each of L-valine, D-alpha-hydroxyisovaleric acid, D-valine, and L-lactic acid linked alternately to form a 36-membered ring. (From Merck Index, 11th ed) Valinomycin is a potassium selective ionophore and is commonly used as a tool in biochemical studies.
D052160	Benzothiazoles	Compounds with a benzene ring fused to a thiazole ring.