Fig. 6.

Morphology of different subsets of interneurons that express different compliments of nAChRs. The lighter line in each tracing is the axon, and the darker line is the dendrite of each illustrated neuron.A, An example of an interneuron with its soma located at the SR/SLM border that responded to nicotinic agonist with only a fast α7 nicotinic response. Its dendrite ramified mostly within SR, but also in SLM. Its axon was contained almost entirely within SLM with a small projection to SR. B, An example of an OLM-type interneuron that responded with both the fast α7 and slow non-α7 nicotinic response. Its dendrite was located entirely within SO and was oriented parallel to the alveus. Its axon had a small projection to SO, but ramified widely in SLM. C, An example of an interneuron that did not respond to nicotinic agonist. Its dendritic tree was found across all layers of CA1, but its axon was confined to an area in and bordering SP. D, A pyramidal cell that does not respond to nicotinic agonist. We detected no difference in the morphologies of pyramidal cell that did not respond to agonist and those that responded with a small response.