The effect of sodium periodate treatment on the modulation of the sodium pump in low-potassium type (LK) sheep red cells by the L antigen

Abstract

1. The action of sodium periodate and neuraminidase on active and passive K + transport in low-potassium type (LK) sheep red cells was investigated in relation to the contribution of the L p and L 1 antigens. 2. Active K + transport in LK sheep red cells was not affected by treatment with sodium periodate (2 mM), or with neuraminidase. 3. Passive K + transport in LK sheep red cells was increased by sodium periodate treatment in a concentration-dependent manner. The increase was not Cl − dependent, and so differed from the increased passive K + uptake resulting from N-ethylmaleimide treatment. 4. HK sheep red cells treated with sodium periodate showed small increases in passive K + uptake, and N-ethylmaleimide treatment used sequentially with sodium periodate resulted in further small increases in passive K + uptake. 5. In LK sheep red cells the stimulation of active K + transport by anti-L was impaired by 50% in cells treated with sodium periodate (2 mM) and was slightly lowered in cells treated with neuraminidase. 6. In LK sheep red cells inhibition of passive K + transport by anti-L was not impaired by sodium periodate treatment (2 mM), or by neuraminidase treatment.