Figure 11.

nAChRs and the MHbV to IPN pathway: summary schematic. A, nAChR-expressing cells of the MHbVI project preferentially to ventral IPN, and the indicated (red text) nAChR subunits are expressed in MHb somata and in presynaptic terminals in IPN. B, MHbVC projects preferentially to central regions of IPN. C, MHbVL projects preferentially to IPR/IPDM. At least two cell types exist in IPR/IPDM. Type I neurons exhibit relatively small inward currents in response to puffed nicotine (NIC) and AMPA and fire tonic action potentials in response to positive current injection. Type II neurons exhibit relatively (compared with Type I cells) large inward currents in response to puffed NIC or AMPA and fire bursts of action potentials following positive current injection.