Synchronous infra-slow oscillations organize ensembles of accessory olfactory bulb projection neurons into distinct microcircuits

Chryssanthi Tsitoura, Sebastian T. Malinowski, Julia Mohrhardt, Rudolf Degen, Brett T. DiBenedictis, Yuan Gao, Katja Watznauer, Kira Gerhold, Maximilian Nagel, Monika Weber, Markus Rothermel, Ileana L. Hanganu-Opatz, Yoram Ben-Shaul, Ian G. Davison, Marc Spehr

Research output: Contribution to journalArticlepeer-review

4 Scopus citations

Abstract

The accessory olfactory system controls social and sexual behavior. In the mouse accessory olfactory bulb, the first central stage of information processing along the accessory olfactory pathway, projection neurons (mitral cells) display infra-slow oscillatory discharge with remarkable periodicity. The physiological mechanisms that underlie this default output state, however, remain controversial. Moreover, whether such rhythmic infra-slow activity patterns exist in awake behaving mice and whether such activity reflects the functional organization of the accessory olfactory bulb circuitry remain unclear. Here, we hypothesize that mitral cell ensembles form synchronized microcircuits that subdivide the accessory olfactory bulb into segregated functional clusters. We use a miniature microscope to image the Ca21 dynamics within the apical dendritic compartments of large mitral cell ensembles in vivo. We show that infra-slow periodic patterns of concerted neural activity, indeed, reflect the idle state of accessory olfactory bulb output in awake male and female mice. Ca21 activity profiles are distinct and glomerulus-specific. Confocal time-lapse imaging in acute slices reveals that groups of mitral cells assemble into microcircuits that exhibit correlated Ca21 signals. Moreover, electrophysiological profiling of synaptic connectivity indicates functional coupling between mitral cells. Our results suggest that both intrinsically rhythmogenic neurons and neurons entrained by fast synaptic drive are key elements in organizing the accessory olfactory bulb into functional microcircuits, each characterized by a distinct default pattern of infra-slow rhythmicity.

Original languageAmerican English
Pages (from-to)4203-4218
Number of pages16
JournalJournal of Neuroscience
Volume40
Issue number21
DOIs
StatePublished - 20 May 2020

Bibliographical note

Publisher Copyright:
© 2020 Society for Neuroscience. All rights reserved.

Keywords

  • Accessory olfactory bulb
  • Chemosensory coding
  • Ensemble formation
  • Mitral cells
  • Neural oscillations
  • Vomeronasal system

Fingerprint

Dive into the research topics of 'Synchronous infra-slow oscillations organize ensembles of accessory olfactory bulb projection neurons into distinct microcircuits'. Together they form a unique fingerprint.

Cite this