Spinal Basis of Direction Control during Locomotion in Larval Zebrafish

Journal of Neuroscience, Journal Year: 2023, Volume and Issue: 43(22), P. 4062 - 4074

Published: May 1, 2023

Navigation requires steering and propulsion, but how spinal circuits contribute to direction control during ongoing locomotion is not well understood. Here, we use drifting vertical gratings evoke directed "fictive" swimming in intact immobilized larval zebrafish while performing electrophysiological recordings from neurons. We find that involves unilateral changes the duration of motor output increased recruitment neurons, without impacting timing spiking across or along body. Voltage-clamp neurons reveal increases phasic excitation inhibition on side turn. Current-clamp premotor interneurons provide two types patterns. A direction-agnostic pattern with balanced turning nonturning sides primarily observed excitatory V2a ipsilateral descending axons, a direction-sensitive preferential dominated by bifurcating axons. Inhibitory V1 are also divided into subsets, although there no detectable morphologic distinction. Our findings support modular propulsion circuits, where distinct subsets inhibitory adjustments move.SIGNIFICANCE STATEMENT Spinal play an essential role coordinating movements locomotion. However, it unclear they participate do interfere coordination. Here have developed system using allows us directly record electrical signals guided visual cues. for coordination others drive asymmetries neuron control. suggest organization enables uninterrupted

Language: Английский

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Elimination of glutamatergic transmission from Hb9 interneurons does not impact treadmill locomotion

Scientific Reports, Journal Year: 2021, Volume and Issue: 11(1)

Published: Aug. 6, 2021

Abstract The spinal cord contains neural circuits that can produce the rhythm and pattern of locomotor activity. It has previously been postulated a population glutamatergic neurons, termed Hb9 interneurons, contributes to rhythmogenesis. These neurons were identified by their expression homeobox gene, Hb9, which is also expressed in motor neurons. We developed mouse line Cre recombinase activity inducible expressing Hb9. then used this eliminate vesicular glutamate transporter 2 from found there no deficits treadmill locomotion. conclude neurotransmission interneurons not required for behaviour. role these remains elusive.

Language: Английский

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A Single Cell Atlas of Spared Tissue Below a Spinal Cord Injury Reveals Cellular Mechanisms of Repair

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2021, Volume and Issue: unknown

Published: April 29, 2021

Abstract After spinal cord injury (SCI), the “spared” tissue below lesion contains undamaged cells that could support or augment recovery, but targeting these requires a clearer understanding of their responses and capacity for repair. Here, we used single nucleus sequencing to profile how each cell type in lumbar changes over time after thoracic injury. We present an atlas dynamic explore two unexpected findings. Amongst neurons, rare types expressed molecular signature regeneration amongst microglia, identified population “trauma associated microglia” (TAM). These TAM were white matter near degenerating axons trophic factors Igf1 Spp1 (OPN). Viral over-expression (OPN) expanded promoted clearance myelin debris. findings expose endogenous mechanisms repair spared neural tissue, uncovering potential candidates targeted therapy.

Language: Английский

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On the Organization of Connexin36 Expression in Electrically Coupled Cholinergic V0c Neurons (Partition Cells) in the Spinal Cord and Their C-terminal Innervation of Motoneurons

Neuroscience, Journal Year: 2022, Volume and Issue: 485, P. 91 - 115

Published: Jan. 26, 2022

Language: Английский

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Modulation of respiratory network activity by forelimb and hindlimb locomotor generators

European Journal of Neuroscience, Journal Year: 2020, Volume and Issue: 52(4), P. 3181 - 3195

Published: March 9, 2020

Early at the onset of exercise, breathing rate accelerates in order to anticipate increasing metabolic demand resulting from extra effort produced. Accordingly, respiratory neural networks are target various input signals originating either centrally or peripherally. For example, during locomotion, activation muscle sensory afferents is able entrain and thereby increase frequency spontaneous rhythmogenesis. Moreover, lumbar spinal engaged generating hindlimb locomotor rhythms also capable activating medullary generators through an ascending excitatory command. However, context quadrupedal influence other cord regions, such as cervical thoracic segments, remains unknown. Using isolated brainstem-spinal preparations neonatal rats mice, we show that cervicothoracic circuitry may contribute locomotion-induced acceleration cycle frequency. As previously observed for CPGs, pharmacological forelimb produces episodes fictive locomotion turn ongoing rhythm. Thoracic neuronal participate indirectly this modulation via both CPG neurons. Furthermore, using light stimulation CHR2-expressing glutamatergic neurons, found involves circuitry. Our results demonstrate rhythm-generating receive inputs circuits responsible coordinating fore- movements. This constitutes a distributed central mechanism contributes matching speed locomotion.

Language: Английский

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