Biomaterial Database

Foreign anions modulate volume set point of sheep erythrocyte K-Cl cotransport. 1991

P K Lauf

Department of Physiology and Biophysics, Wright State University, Dayton, Ohio 45401-0927.

Preequilibration at 37 degrees C in isosmotic media with Cl replaced by lyotropic (foreign) anions reversibly increased Cl-dependent K efflux and Rb influx, the inhibition by furosemide, and thus K-Cl cotransport in low-K but not in high-K sheep erythrocytes with the following order of effectiveness: SCN greater than I greater than NO3 greater than Cl = Br. This effect depended on time, temperature, and anion concentration and was reversible. Preincubation in isosmotic SCN at 37 degrees C stimulated K-Cl flux in anisosmotic Cl media (370-240 mosM) by increasing the volume sensitivity through shifting the point of zero K-Cl flux by approximately 100 mosmol. Thus even shrunken cells exhibited K-Cl cotransport. Preincubation in hyperosmotic SCN or Cl (440 mosM) followed by K flux in hyposmotic Cl (240 mosM) caused a 30-min lag phase that was absent when cells were swollen only. Hence, foreign anions increased the K flux rate in Cl, suggesting upregulation of K-Cl cotransport through new sites or higher turnover per transporter. The anions must act directly on proteins and/or lipids as the accompanying intracellular pH (pHi) changes were too small to attribute the K-Cl flux activation to cellular acidification. After thiol alkylation, which also activates K-Cl cotransport, SCN preexposure at 37 degrees C became ineffective. Carbethoxylation significantly reduced the foreign anion enhancement of K-Cl cotransport and abolished K efflux in Br. It is concluded that interaction of anions through carbethoxylation-sensitive sites with thiols may determine the level of K-Cl cotransport activity.

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
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.
D002352	Carrier Proteins	Proteins that bind or transport specific substances in the blood, within the cell, or across cell membranes.	Binding Proteins,Carrier Protein,Transport Protein,Transport Proteins,Binding Protein,Protein, Carrier,Proteins, Carrier
D002712	Chlorides	Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.	Chloride,Chloride Ion Level,Ion Level, Chloride,Level, Chloride Ion
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
D005665	Furosemide	A benzoic-sulfonamide-furan. It is a diuretic with fast onset and short duration that is used for EDEMA and chronic RENAL INSUFFICIENCY.	Frusemide,Fursemide,Errolon,Frusemid,Furanthril,Furantral,Furosemide Monohydrochloride,Furosemide Monosodium Salt,Fusid,Lasix
D000096922	K Cl- Cotransporters	A subclass of symporters that specifically transport POTASSIUM and CHLORIDE ions across cellular membranes. Potassium chloride cotransporters play roles in regulating cell volume and intracellular chloride concentration.	Electroneutral Potassium-Chloride Co-transporter 3,Electroneutral Potassium-Chloride Cotransporter 3,K Cl- Co-transporters,K(+), Cl(-)-Co-transporters,K(+), Cl(-)-Cotransporters,K-Cl Co-transporter,K-Cl Co-transporter 3,K-Cl Cotransporter,K-Cl Cotransporter 3,KCC2 Co-transporter,KCC2 Cotransporter,KCC3 Co-transporter,KCC3 Cotransporter,KCC4 Co-transporter,KCC4 Cotransporter,Potassium-Chloride Co-transporter 2,Potassium-Chloride Co-transporter 4,Potassium-Chloride Co-transporters,Potassium-Chloride Cotransporter 2,Potassium-Chloride Cotransporter 4,Potassium-Chloride Cotransporters,Potassium-Chloride Symporters,SLC12A5 Protein,SLC12A6 Protein,SLC12A7 Protein,Solute Carrier Family 12 Member 5,Solute Carrier Family 12 Member 6,Solute carrier family 12 member 7,Cl- Co-transporters, K,Co-transporter 2, Potassium-Chloride,Co-transporter 3, K-Cl,Co-transporter 4, Potassium-Chloride,Co-transporter, K-Cl,Co-transporter, KCC2,Co-transporter, KCC3,Co-transporter, KCC4,Co-transporters, K Cl-,Co-transporters, Potassium-Chloride,Cotransporter, K-Cl,Cotransporter, KCC2,Cotransporter, KCC3,Cotransporter, KCC4,Cotransporters, K Cl-,Cotransporters, Potassium-Chloride,Electroneutral Potassium Chloride Co transporter 3,Electroneutral Potassium Chloride Cotransporter 3,K Cl Co transporter,K Cl Co transporter 3,K Cl Co transporters,K Cl Cotransporter,K Cl Cotransporter 3,K Cl Cotransporters,KCC2 Co transporter,KCC3 Co transporter,KCC4 Co transporter,Potassium Chloride Co transporter 2,Potassium Chloride Co transporter 4,Potassium Chloride Co transporters,Potassium Chloride Cotransporter 2,Potassium Chloride Cotransporter 4,Potassium Chloride Cotransporters,Potassium Chloride Symporters,Protein, SLC12A5,Protein, SLC12A6,Protein, SLC12A7
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
D000838	Anions	Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.	Anion