Biomaterial Database

Increased inward passive permeability in vitro to sodium in uraemic erythrocytes. 1996

D B Corry, and C C Ellis, and M L Tuck

Department of Medicine, Olive View Medical Center, Sylmar, California 91342-1495, USA.

1. We have reported a normal sodium (Na) pump, but decreased loop-diuretic-sensitive Na efflux in erythrocytes from patients with chronic renal failure on haemodialysis, suggesting a different mode of co-transport in uraemia. 2. The present work extends these findings and examines in vitro simultaneous unidirectional and radiolabelled Na and K fluxes through the Na/K/Cl co-transport and the Na/K pump in washed erythrocytes from seven subjects with chronic renal failure and seven controls. Erythrocyte cytosolic calcium was also examined. 3. Ouabain-sensitive 86Rb influx was similar in patients and controls (1.76 +/- 0.19 versus 1.72 +/- 0.13 mmol h-1 litre-1 of erythrocytes) as was ouabain-sensitive 22Na efflux (3.62 +/- 0.36 versus 4.04 +/- 0.39 mmol h-1 litre-1 of erythrocytes). 4. Bumetanide-sensitive 86Rb and 22Na influx and 22Na efflux were measured at three concentrations (4, 8 and 12 mmol/l) of external K. In chronic renal failure, mean bumetanide-sensitive 22Na efflux was decreased at all external K concentrations compared with controls, and at physiological concentrations (4 mmol/l) external K was lower than controls (0.14 +/- 0.01 versus 0.38 +/- 0.05 mmol h-1 litre-1 of erythrocytes, P < 0.01). Mean bumetanide-sensitive 86Rb influx was also reduced in chronic renal failure at all external K concentrations, and at 4 mmol/l external K was lower than controls (0.13 +/- 0.04 versus 0.34 +/- 0.04 mmol h-1 litre-1 of erythrocytes, P < 0.01). Conversely, bumetanide-sensitive 22Na influx was markedly increased at all external K levels in chronic renal failure, and at 4 mmol/l external K values were elevated compared with controls (0.64 +/- 0.18 versus 0.34 +/- 0.04 mmol h-1 litre-1 of erythrocytes, P < 0.001). The mean cytosolic calcium concentration was higher in erythrocytes in chronic renal failure than controls (134.4 +/- 8.6 versus 63.7 +/- 5.8 nmol/l, P < 0.001). 5. Thus, in washed erythrocytes incubated in artificial media there is a markedly increased ouabain-insensitive Na influx in subjects with chronic renal failure which might be explained in part by the higher levels of cytosolic calcium. In vivo, this cell defect combined with suppression of the Na/K pump could lead to intracellular Na accumulation and play a role in uraemic complications.

UI	MeSH Term	Description	Entries
D007676	Kidney Failure, Chronic	The end-stage of CHRONIC RENAL INSUFFICIENCY. It is characterized by the severe irreversible kidney damage (as measured by the level of PROTEINURIA) and the reduction in GLOMERULAR FILTRATION RATE to less than 15 ml per min (Kidney Foundation: Kidney Disease Outcome Quality Initiative, 2002). These patients generally require HEMODIALYSIS or KIDNEY TRANSPLANTATION.	ESRD,End-Stage Renal Disease,Renal Disease, End-Stage,Renal Failure, Chronic,Renal Failure, End-Stage,Chronic Kidney Failure,End-Stage Kidney Disease,Chronic Renal Failure,Disease, End-Stage Kidney,Disease, End-Stage Renal,End Stage Kidney Disease,End Stage Renal Disease,End-Stage Renal Failure,Kidney Disease, End-Stage,Renal Disease, End Stage,Renal Failure, End Stage
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
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.
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
D002712	Chlorides	Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.	Chloride,Chloride Ion Level,Ion Level, Chloride,Level, Chloride Ion
D004791	Enzyme Inhibitors	Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.	Enzyme Inhibitor,Inhibitor, Enzyme,Inhibitors, Enzyme
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