title: Ionic requirements for intracellular pH regulation in rainbow trout hepatocytes.
abstract: The ionic requirements for pH regulation in isolated rainbow trout (Salmo gairdneri) hepatocytes were determined by manipulation of intracellular pH (pHi; measured by the dimethyloxazolidinedione distribution technique) by NH4Cl prepulse and changes in external [CO2] in the presence and absence of various drugs and external ions. The presence of a Na+/H+(NH+4) exchange system is supported by the following results: 1) the rate of recovery from an acid load is decreased by amiloride (0.5 mM) or reduction of external [Na+]; 2) the rate of 22Na uptake is increased during recovery from an acid load, and this increase in amiloride sensitive. The presence of a Cl-/HCO3- exchange system is supported by the observations that 1) pHi is increased, and 2) rates of recovery of pHi from acid loading are enhanced, by exposure to 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (0.5 mM) and reductions in external [Cl-]. Further studies are required to determine the role of these exchange processes during physiological pHi perturbations.
mesh_terms: D000143:Acids / Q000494:pharmacology; D000818:Animals; D001639:Bicarbonates / Q000378:metabolism; D001826:Body Fluids / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007424:Intracellular Fluid / Q000378:metabolism*; D007474:Ion Exchange; D007477:Ions; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D014337:Trout
chemical_list: D000143:Acids; D001639:Bicarbonates; D002712:Chlorides; D007477:Ions; D006859:Hydrogen; D012964:Sodium