Abstract
Identified neurons from the abdominal ganglion of the marine mollusc Aplysia californica make specific transmitter-mediated synapses in dissociated cell culture. The cholinergic interneuron L10 makes synapses in vitro with one group of its follower cells, the left upper quadrant cells, and these connections exhibit the features of these synapses in vivo when the postsynaptic cells are plated with their initial axon segments. Furthermore, L10 will avoid making synapses with right upper quadrant cells, which contain cholinergic receptors but do not synapse with L10 in vivo. This in vitro system can therefore be used as a model in which to study the development of specific neuronal connections.