title: Synchronization of an embryonic network of identified spinal interneurons solely by electrical coupling.
abstract: There is a need to understand the mechanisms of neural synchronization during development because correlated rhythmic activity is thought to be critical for the establishment of proper connectivity. The relative importance of chemical and electrical synapses for synchronization of electrical activity during development is unclear. We examined the activity patterns of identified spinal neurons at the onset of motor activity in zebrafish embryos. Rhythmic activity appeared early and persisted upon blocking chemical neurotransmission but was abolished by inhibitors of gap junctions. Paired recordings revealed that active spinal neurons were electrically coupled and formed a simple network of motoneurons and a subset of interneurons. Thus, the earliest spinal central pattern generator consists of synchronously active, electrically coupled neurons.
authors.affiliation: Centre for Research in Neuroscience, Montreal General Hospital Research Institute, Montréal, Québec, Canada H3G 1A4.
authors.forename: L
authors.initials: L
authors.lastname: Saint-Amant
authors.forename: P
authors.initials: P
authors.lastname: Drapeau
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D001030:Apamin / Q000494:pharmacology; D001369:Axons / Q000648:ultrastructure; D001755:Blastocyst / Q000187:drug effects / Q000502:physiology; D001905:Botulinum Toxins / Q000494:pharmacology; D019274:Botulinum Toxins, Type A; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005456:Fluorescent Dyes / Q000032:analysis; D017629:Gap Junctions / Q000187:drug effects / Q000502:physiology; D007395:Interneurons / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects; D008856:Microscopy, Fluorescence; D009024:Morphogenesis; D009043:Motor Activity / Q000502:physiology*; D009415:Nerve Net / Q000196:embryology* / Q000502:physiology; D018408:Patch-Clamp Techniques; D010507:Periodicity; D017470:Receptors, Glutamate / Q000187:drug effects; D013116:Spinal Cord / Q000166:cytology / Q000196:embryology*; D013331:Strychnine / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology; D015027:Zebrafish
chemical_list: D018691:Excitatory Amino Acid Antagonists; D005456:Fluorescent Dyes; D017470:Receptors, Glutamate; C096323:rimabotulinumtoxinB; D001030:Apamin; D013779:Tetrodotoxin; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D015763:2-Amino-5-phosphonovalerate; D001905:Botulinum Toxins; D019274:Botulinum Toxins, Type A; D013331:Strychnine