Biomaterial Database

Regulatory volume decrease in cultured astrocytes. I. Potassium- and chloride-activated permeability. 1994

H Pasantes-Morales, and R A Murray, and L Lilja, and J Morán

Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City.

Regulatory volume decrease (RVD) in detached cerebellar astrocytes in culture after acute exposure to hyposmolarity was characterized in this and the accompanying paper [H. Pasantes-Morales, R. A. Murray, R. Sanches-Olea, and J. Moran. Am. J. Physiol. 266 (Cell Physiol. 35): C172-C178, 1994]. RVD was independent of extracellular calcium, was accelerated at pH 8-9 and retarded at pH 6, and was reduced at temperatures < 18 degrees C. The cationic pathway activated by hyposmolarity was specific for K+ and Rb+, since RVD was abolished and secondary swelling occurred when these ions replaced Na+. However, Li+, choline, tris(hydroxymethyl)aminomethane, and glucosamine, all as Cl- salts, did not affect RVD. The anion pathway was unselective, since RVD was inhibited when NaCl was replaced by anion K+ salts with a permeability rank of SCN- = I- > NO3- > Cl- > benzoate > acetate >> SO3- > gluconate. RVD was unaffected by bumetanide (50 microM) and weakly inhibited by furosemide (2 mM). Quinidine but not other K+ channel blockers inhibited RVD, and its effect was reversed by gramicidin. RVD was inhibited by 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid and dipyridamole but not by diphenylamine-2-carboxylate or anthracene-9-carboxylate. These results suggest that diffusion possibly via channels rather than cotransporters is involved in the swelling-activated K+ and Cl- fluxes. Gramicidin did not change astrocyte volume in isosmotic conditions, but greatly accelerated RVD, suggesting that low Cl- permeability in isosmotic conditions markedly increases by swelling, thus making K+ permeability the rate-limiting step for RVD.

UI	MeSH Term	Description	Entries
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.
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
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
D002412	Cations	Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.	Cation
D002463	Cell Membrane Permeability	A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.	Permeability, Cell Membrane
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D002712	Chlorides	Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.	Chloride,Chloride Ion Level,Ion Level, Chloride,Level, Chloride Ion
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
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