||Human Homo sapiens
||Gasbjerg PK, Knauf PA, Brahm J. Kinetics of bicarbonate transport in human red blood cell membranes at body temperature. J Gen Physiol. 1996 Dec108(6):565-75. p.571 left column top paragraphPubMed ID8972394
||"On the basis of studies of chloride transport mainly at 0°C, the "ping-pong model" for anion exchange was proposed (Gunn and Frohlich, 1979 Frohlich and Gunn, 1986). According to this model, a transport site in the protein, unloaded or loaded with an anion, may either face the internal or the external compartment."
experiments with intact red blood cells (Gasbjerg et al. 1993, PMID 8393066) show that chloride permeability can be 99.999% inhibited to 6×10^-9cm/sec by 50µM DIDS, i.e., to a level as low as in lipid bilayers. This low anion permeability could not be reached for bicarbonate, in the first place because the inescapable spontaneous dehydration equals an apparent bicarbonate permeability of 2.4×10^-7cm/sec (pH 7.8). and secondly, because there is an additional contribution that increased the permeability fivefold to 1.2×10^-6cm/sec."