title: Local interneurons define functionally distinct regions within lobster olfactory glomeruli
abstract: Whole-cell recording coupled with biocytin injection revealed four types of interneurons intrinsic to the olfactory lobe (OL) of the spiny lobster Panulirus argus. Each type of neuron had a distinct pattern of arborization within the three anatomically defined regions of OL glomeruli (cap, subcap and base). Type I interneurons innervated all three regions, while types II, III and IV branched only in the cap, subcap and base, respectively. Type I interneurons responded to electrical stimulation of the antennular (olfactory) nerve with a burst of 1&shy;20 action potentials and a 1&shy;10 s depolarization. Type II (cap) interneurons responded to the same input with a burst of 1&shy;3 action potentials followed by a shorter hyperpolarization. Type III (subcap) interneurons responded with a burst of 1&shy;6 action potentials followed by a delayed, 0.5&shy;4 s depolarization. Type IV (base) interneurons responded with a brief depolarization or a burst of 1&shy;3 action potentials followed by a 1 s hyperpolarization. The regionalized arborization and the different response properties of the type II, III and IV interneurons strongly imply that lobster olfactory glomeruli contain functionally distinct regions, a feature that should be useful in understanding the multiple synaptic pathways involved in processing olfactory input.
authors.initials: M
authors.lastname: Wachowiak
authors.initials: C
authors.lastname: Diebel
authors.initials: B
authors.lastname: Ache