Ionophore-mediated Ca2+ countertransport: role of Na+, Li+ or H+ gradient.
In an artificial system, the ionophore A23187, which transports Ca2+ but not Na+, is able to mediate the uphill translocation of Ca2+ from one aqueous medium to another across an organic immiscible phase, provided that a Na+, Li+ or H+ gradient is imposed on the system. Therefore, in the process known as Na-Ca countertransport, the downhill influx of Na+ may not be necessary for causing Ca2+ extrusion against its electrochemical gradient.
D000900:Anti-Bacterial Agents / Q000378:metabolism*; D001693:Biological Transport, Active; D000001:Calcimycin / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002412:Cations; D004563:Electrochemistry; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008094:Lithium / Q000378:metabolism*; D008954:Models, Biological; D012964:Sodium / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D002412:Cations; D000001:Calcimycin; D006859:Hydrogen; D008094:Lithium; D012964:Sodium; D002118:Calcium