CHLORIDE DISTRIBUTION BETWEEN RED BLOOD CELLS AND PLASMA IN DOGFISH (SCYLIORHINUS CANICULA)

The chloride distribution between erythrocytes and plasma of the dogfish, Scyliorhinus canicula, was determined at two levels of Pco2 in vitro. At the higher Pco2 plasma chloride was consistently lower than at the low Pco2, whereas the intracellular chloride changed in the opposite direction. The Donnan ratio rcl was 0.50 at low Pco2 and 0.57 at high Pco2. The chloride shift corresponded to a change in chemically-bound CO2 of 7 meq per unit pH. The data support the hypothesis that dogfish hemoglobin has similar physicochemical properties with respect to the CO2 transport as has mammalian hemoglobin. © 1969.