In vitro connections between Lymnaea and Helisoma identified interneurons and their follower cells.

The mechanisms that underly the specificity of synaptic connections are poorly understood. In this study we used two homologous interneurons, the giant dopamine cell (GDC), in two species of pond snails, Lymnaea and Helisoma. We examined the ability of the Lymnaea GDC to form specific synapses with known follower or non-follower cells in vitro. Similar tests were performed for the Helisoma GDC. Both of these interneurons form appropriate connections not only with homologous follower neurons, but also with follower neurons from the alternative species. These results suggest that common mechanisms of cell recognition and synapse formation exist in the nervous systems of these two different families of molluscs.