PUBLICATION
Common Sensory Inputs and Differential Excitability of Segmentally Homologous Reticulospinal Neurons in the Hindbrain
- Authors
- Nakayama, H., and Oda, Y.
- ID
- ZDB-PUB-040402-2
- Date
- 2004
- Source
- The Journal of neuroscience : the official journal of the Society for Neuroscience 24(13): 3199-3209 (Journal)
- Registered Authors
- Oda, Yoichi
- Keywords
- Mauthner cell, reticulospinal neurons, segmental homologs, eighth nerve afferents, recurrent inhibition, dendrotoxin
- MeSH Terms
-
- Acoustic Stimulation
- Afferent Pathways/physiology*
- Animals
- Elapid Venoms/pharmacology
- Electric Stimulation
- Escape Reaction/physiology
- Evoked Potentials/drug effects
- Evoked Potentials/physiology
- Excitatory Postsynaptic Potentials/drug effects
- Excitatory Postsynaptic Potentials/physiology
- Fluorescent Dyes
- GABA Antagonists/pharmacology
- Glycine Agents/pharmacology
- Goldfish/physiology*
- Kv1.2 Potassium Channel
- Neurons/classification
- Neurons/drug effects
- Neurons/physiology*
- Potassium Channels/biosynthesis
- Potassium Channels/drug effects
- Potassium Channels, Voltage-Gated*
- Rhombencephalon/cytology
- Rhombencephalon/physiology*
- Spinal Cord/physiology*
- PubMed
- 15056699 Full text @ J. Neurosci.
Citation
Nakayama, H., and Oda, Y. (2004) Common Sensory Inputs and Differential Excitability of Segmentally Homologous Reticulospinal Neurons in the Hindbrain. The Journal of neuroscience : the official journal of the Society for Neuroscience. 24(13):3199-3209.
Abstract
In the hindbrain of zebrafish and goldfish, reticulospinal (RS) neurons are arranged in seven segments, with segmental homologs in adjacent segments. The Mauthner cell (M-cell) in the fourth segment (r4) is known to trigger fast escape behavior. Its serial homologs, MiD2cm in r5 and MiD3cm in r6, are predicted to contribute to this behavior, which can be evoked by head-tap stimuli. However, little is known about their input-output properties. Therefore, we studied afferent projections from the auditory posterior eighth nerve (pVIIIn) and firing properties of MiD2cm and MiD3cm for comparison with the M-cell in adult goldfish. Labeling of RS neurons and the pVIIIn afferents with fluorescent tracers showed that the pVIIIn projected to r4-r6. Tone burst and electrical stimulation of the pVIIIn evoked EPSPs in the M-cell, MiD2cm, and MiD3cm. Stepwise depolarization typically elicited a single spike at the onset in the M-cell but repetitive spiking in MiD2cm and MiD3cm. This atypical property of the M-cell was mediated by dendrotoxin-I (DTX-I)-sensitive voltage-gated potassium channels together with recurrent inhibition, because combined application of DTX-I, strychnine, and bicuculline led to continuous repetitive firing in M-cells. The M-cell but not MiD2cm or MiD3cm expressed Kv1.2, a DTX-I-sensitive potassium channel subunit. Thus, the M-cell and its segmental homologs may sense common auditory information but send different outputs to the spinal circuits to control adaptive escape behavior.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping