The culture of rat submandibular ganglion cells is described. The neurons can be distinguished from the non-neuronal cells in the cultures by their morphology. Recording with whole-cell voltage-clamp techniques indicates that the neurons have resting potentials of about -55 mV and that the kinetics of the ionic channels opened by locally perfused acetylcholine (ACh) are very similar to those previously observed in adult submandibular ganglion neurons. The major differences observed are that the recorded cell input impedances are much higher than those recorded with microelectrodes from adult neurons and that the sensitivity of the cultured neurons to ACh is much less than that of the adult neurons. Whether the latter is due to changed receptor properties or to the presence of fewer receptors is not known.