Expression of a foreign G-protein coupled receptor modulates the excitability of the peptidergic bag cell neurons of Aplysia

Brief afferent stimulation of the bag cell neurons can trigger a sustained period of spontaneous firing (the 'afterdischarge'). Pharmacological activa tion of a number of second messenger pathways has previously been shown to partially replicate this behavior. One strategy to identify additional path ways may be to heterologously express a variety of G-protein coupled recept ors in bag cell neurons, then test whether receptor activation can induce a n afterdischarge. We find that expression of the 1 alpha metabotropic gluta mate receptor in single bag cell neurons mimics some features of the afterd ischarge. This approach is thus feasible and may allow the reconstruction o f different components of afterdischarge in the absence of the afferent inp ut. (C) 1998 Published by Elsevier Science Ireland Ltd. All rights reserved .