title: Intracellular pH, H ion flux and H ion permeability coefficient in bullfrog toe muscle.
abstract: 1. The dimethyloxazolidinedione (DMO) technique was used to estimate intracellular pH (pH(i)) in bullfrog toe muscles incubated in vitro. The control value of pH(i) was 7.16 + +/- 0.01 (S.D.).2. pH(i) was affected by changes in P(CO2) and external bicarbonate ion concentration ([HCO(3) (-)](0)). At a given P(CO2), decreasing the external [HCO(3) (-)] was more effective in lowering pH(i) than increasing the external [HCO(3) (-)] was in increasing pH(i).3. On the assumption that the changes in pH(i) were due to hydrogen ion [H(+)) movements across the membrane, a H(+) flux of 10(-13) mole/cm(2). sec was calculated. The corresponding H(+) permeability coefficient was 10(-3) cm/sec.4. The variability of the tissue CO(2) buffer value was examined.
mesh_terms: D000818:Animals; D001001:Anura; D001639:Bicarbonates / Q000494:pharmacology; D002021:Buffers; D002245:Carbon Dioxide; D002463:Cell Membrane Permeability; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D009132:Muscles / Q000378:metabolism*; D010080:Oxazoles; D011892:Rana catesbeiana; D013997:Time Factors
chemical_list: D001639:Bicarbonates; D002021:Buffers; D010080:Oxazoles; D002245:Carbon Dioxide; D006859:Hydrogen