On the theory of ion transport across the nerve membrane, VII. Cooperativity between channels of a large square lattice.

The exact kinetics of a 10 x 10 Ising system (periodic boundary conditions) with two-state channels arranged in a square lattice was studied by computer simulation. With all three values of the cooperativity parameter used, no induction in the K(+)-current curve was obtained. This confirms one of our previous conclusions concerning K(+) channels in the squid axon membrane: models with interacting channels arranged in a twodimensional lattice (Adam's model) are apparently excluded. Other topics included: equilibrium properties; short-range pair correlation functions; phase transition.