title: Interdependent Conductances Drive Infraslow Intrinsic Rhythmogenesis in a Subset of Accessory Olfactory Bulb Projection Neurons.
abstract: The accessory olfactory system controls social and sexual behavior. However, key aspects of sensory signaling along the accessory olfactory pathway remain largely unknown. Here, we investigate patterns of spontaneous neuronal activity in mouse accessory olfactory bulb mitral cells, the direct neural link between vomeronasal sensory input and limbic output. Both in vitro and in vivo, we identify a subpopulation of mitral cells that exhibit slow stereotypical rhythmic discharge. In intrinsically rhythmogenic neurons, these periodic activity patterns are maintained in absence of fast synaptic drive. The physiological mechanism underlying mitral cell autorhythmicity involves cyclic activation of three interdependent ionic conductances: subthreshold persistent Na(+) current, R-type Ca(2+) current, and Ca(2+)-activated big conductance K(+) current. Together, the interplay of these distinct conductances triggers infraslow intrinsic oscillations with remarkable periodicity, a default output state likely to affect sensory processing in limbic circuits.
  
  
  CONCLUSIONS
  We show for the first time that some rodent accessory olfactory bulb mitral cells-the direct link between vomeronasal sensory input and limbic output-are intrinsically rhythmogenic. Driven by ≥ 3 distinct interdependent ionic conductances, infraslow intrinsic oscillations show remarkable periodicity both in vitro and in vivo. As a novel default state, infraslow autorhythmicity is likely to affect limbic processing of pheromonal information.
authors.affiliation: Department of Chemosensation, Institute for Biology II.
authors.forename: Monika
authors.initials: M
authors.lastname: Gorin
authors.affiliation: Department of Chemosensation, Institute for Biology II.
authors.forename: Chryssanthi
authors.initials: C
authors.lastname: Tsitoura
authors.affiliation: School of Medicine, Department of Medical Neurobiology, The Hebrew University of Jerusalem, Jerusalem, 91120 Israel.
authors.forename: Anat
authors.initials: A
authors.lastname: Kahan
authors.affiliation: Department of Chemosensation, Institute for Biology II.
authors.forename: Katja
authors.initials: K
authors.lastname: Watznauer
authors.affiliation: Department of Chemosensation, Institute for Biology II.
authors.forename: Daniela R
authors.initials: DR
authors.lastname: Drose
authors.affiliation: Institute for Theoretical Information Technology, RWTH Aachen University, D-52074 Aachen, Germany.
authors.forename: Martijn
authors.initials: M
authors.lastname: Arts
authors.affiliation: Institute for Theoretical Information Technology, RWTH Aachen University, D-52074 Aachen, Germany.
authors.forename: Rudolf
authors.initials: R
authors.lastname: Mathar
authors.affiliation: Biocomputation Group, University of Hertfordshire, Hatfield, Hertfordshire AL10 9AB, United Kingdom, and.
authors.forename: Simon
authors.initials: S
authors.lastname: O'Connor
authors.affiliation: Developmental Neurophysiology, Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, D-20251 Hamburg, Germany.
authors.forename: Ileana L
authors.initials: IL
authors.lastname: Hanganu-Opatz
authors.affiliation: School of Medicine, Department of Medical Neurobiology, The Hebrew University of Jerusalem, Jerusalem, 91120 Israel.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Ben-Shaul
authors.affiliation: Department of Chemosensation, Institute for Biology II, m.spehr@sensorik.rwth-aachen.de.
authors.forename: Marc
authors.identifier: http://orcid.org/0000-0001-6616-4196
authors.initials: M
authors.lastname: Spehr
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002317:Cardiovascular Agents / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D054501:Group II Phospholipases A2; D066298:In Vitro Techniques; D051379:Mice; D008810:Mice, Inbred C57BL; D008959:Models, Neurological; D009474:Neurons / Q000145:classification / Q000187:drug effects / Q000502:physiology*; D009830:Olfactory Bulb / Q000166:cytology*; D009833:Olfactory Pathways / Q000502:physiology*; D010507:Periodicity; D011743:Pyrimidines / Q000494:pharmacology; D013111:Spider Venoms / Q000494:pharmacology; D014633:Valine / Q000031:analogs & derivatives / Q000494:pharmacology; D020867:omega-Agatoxin IVA / Q000494:pharmacology
chemical_list: D002121:Calcium Channel Blockers; D002317:Cardiovascular Agents; D018691:Excitatory Amino Acid Antagonists; D011743:Pyrimidines; C115521:SNX 482; D013111:Spider Venoms; D020867:omega-Agatoxin IVA; C082246:ICI D2788; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; C056639:2-amino-5-phosphopentanoic acid; D054501:Group II Phospholipases A2; D014633:Valine; D002118:Calcium
keywords: intrinsic oscillations; mitral cell; olfactory bulb; pacemaker; rhythmogenesis; vomeronasal system