title: Multimodal cross-talk of olfactory and gustatory information in the endopiriform nucleus in rats.
abstract: The endopiriform nucleus (EPN) is a large group of multipolar cells located in the depth of the piriform cortex (PC). Although many studies have suggested that the EPN plays a role in temporal lobe epilepsy, the normal function of the EPN remains to be elucidated. By using optical imaging of coronal brain slice preparations with voltage-sensitive dye, we found signal propagation from the PC or gustatory cortex (GC) to the EPN in normal medium. In our previous research, we failed to elicit a reliable signal reproducibly in the EPN by single stimulation either to the PC or GC. In our current research, we found that a double-pulse stimulation to either the PC or GC (interpulse interval: 20-100 ms) induced robust signal propagation to the EPN through excitation in the agranular division of the insular cortex (AI), with further extension to the claustrum. Finally, double site paired-pulse stimulation to the PC and GC also evoked excitation in the AI, claustrum, and EPN. These results suggest that the EPN has dual roles: 1) further processing of modality-specific olfactory and gustatory information from the PC and GC, respectively and 2) synergistic integration of PC-derived olfactory information and GC-derived gustatory information.
authors.affiliation: Department of Physiology, Kanazawa Medical University, Uchinada, Ishikawa 920-0293, Japan. tokio@kanazawa-med.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Sugai
authors.forename: R
authors.initials: R
authors.lastname: Yamamoto
authors.forename: H
authors.initials: H
authors.lastname: Yoshimura
authors.forename: N
authors.initials: N
authors.lastname: Kato
mesh_terms: D000818:Animals; D004558:Electric Stimulation; D004594:Electrophysiology; D009474:Neurons / Q000502:physiology; D009833:Olfactory Pathways / Q000166:cytology / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013649:Taste / Q000502:physiology*