Mozhayeva G N, Naumov A P, Negulyaev Y A
Biochim Biophys Acta. 1981 Apr 22;643(1):251-5. doi: 10.1016/0005-2736(81)90238-8.
The inhibition of the sodium current in nodal membrane at low pH external solutions was studied under voltage clamp conditions. Analysis of the data for membrane potentials from +10 to +150 mV shows that the inhibition of the Na+ currents at high positive potentials cannot be described by a titration curve of a single acid group. The data can be explained on assumption that the conductance of each sodium channel is controlled by two acid groups: one is located within the pore, the other just near the outer mouth of the pore. The affinity of both groups for H+ is estimated.
