The kinetic constants of steps 0, 1, and 2, deduced from the effects of ATP and ADP on 2πc. For the ATP study (in A, B, D, and E), n = 7 for Neb⁺ fibers, and n = 9 for the Neb⁻ fibers. For the ADP study (C), n = 10 for Neb⁺ fibers and n = 5 for Neb⁻ fibers. K₂ = k₂/k₋₂. Assoc, Association; Equilib, Equilibrium; const, constant.