Multiple conductance change associated with the slow excitatory potential in mammalian sympathetic neurons.

When the membrane potential was manually clamped, the non-cholinergic excitatory potential was associated with either a sustained increase, an initial decrease followed by a prolonged increase or no apparent change in neuronal input resistance. In the majority of neurons studied, the amplitude of non-cholinergic depolarization was augmented upon conditioning hyperpolarization, whereas it was attenuated in a low Na solution. The results are consistent with the suggestion that the non-cholinergic depolarization may be generated by a change of multiple conductances that may include GNa activation and GK inactivation.