Functional Characterization of Di6 Interneurons in the Neonatal Mouse Spinal Cord 1 2 Abbreviated Title: Characterization of Di6 Neurons during Locomotion. 3 4 Activity of Di6 Neurons during Fictive Locomotion

Abstract

46 Our understanding of the neural control of locomotion has been greatly enhanced by the 47 ability to identify and manipulate genetically defined populations of interneurons that comprise 48 the locomotor central pattern generator (CPG). To date, the dI6 interneurons are one of the few 49 populations that settle in the ventral region of the postnatal spinal cord which have not been 50 investigated. In the present study, we utilize a novel transgenic mouse line to 51 electrophysiologically characterize dI6 interneurons located close to the central canal and study 52 their function during fictive locomotion. The majority of dI6 cells investigated were found to be 53 rhythmically active during fictive locomotion and could be divided into two 54 electrophysiologically distinct populations of interneurons. The first fired rhythmic trains of 55 action potentials that were loosely coupled to ventral root output, and contained several intrinsic 56 membrane properties of rhythm generating neurons raising the possibility that these cells may be 57 involved in the generation of rhythmic activity in the locomotor CPG. The second fired rhythmic 58 trains of action potentials that were tightly coupled to ventral root output and lacked intrinsic 59 oscillatory mechanisms, indicating that these neurons may be driven by a rhythm generating 60 network. Together these results indicate that dI6 neurons comprise an important component of 61 the locomotor CPG that participate in multiple facets of motor behavior. 62

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Cite this paper

@inproceedings{Dyck2012FunctionalCO, title={Functional Characterization of Di6 Interneurons in the Neonatal Mouse Spinal Cord 1 2 Abbreviated Title: Characterization of Di6 Neurons during Locomotion. 3 4 Activity of Di6 Neurons during Fictive Locomotion}, author={Jason R. B. Dyck and Guillermo M Lanuza and Simon Gosgnach}, year={2012} }