Changes of intracellular Ca++ as measured by arsenazo III in relation to the K permeability of human erythrocyte ghosts.
A Ca-sensitive dye, arsenazo III, has been incorporated into resealed human erythrocyte ghosts and calibrated to monitor continuously micromolar concentrations of intracellular ionized Ca ([Ca++]i). When the external concentration of Ca is much greater than [Ca++]i, [Ca++]i increases because of a net balance between Ca influx and efflux. Dynamic changes in [Ca++]i regulate K efflux, which in turn may influence the rate of Ca influx. A procedure for purifying arsenazo III is also described.
D001391:Azo Compounds; D002118:Calcium / Q000378:metabolism*; D002463:Cell Membrane Permeability; D004396:Coloring Agents; D004910:Erythrocyte Membrane / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D011188:Potassium / Q000378:metabolism*; D013053:Spectrophotometry
D001391:Azo Compounds; D004396:Coloring Agents; D011188:Potassium; D002118:Calcium