Propriospinal neurons are sufficient for bulbospinal transmission of the locomotor command signal in the neonatal rat spinal cord

This study investigates the role of propriospinal neurons in transmitting signals from the brainstem to the spinal cord to control movement in neonatal rats. The researchers examined whether these neurons, without direct long connections from the brainstem, could still mediate the activation of the locomotor network. The researchers used staggered hemisections in the spinal cord to block long direct pathways from the brainstem. They then stimulated the brainstem and recorded activity in the lumbar ventral roots to see if locomotor-like activity could be evoked. The study also explored whether stimulating propriospinal neurons chemically could promote locomotor activity, even when brainstem stimulation alone was ineffective. The results suggest that propriospinal neurons are sufficient for transmitting descending locomotor command signals.

• 1
  Locomotor-like activity could be evoked by brainstem stimulation even with staggered spinal cord hemisections that disrupted long direct pathways.
• 2
  Neurochemical excitation of propriospinal neurons, when combined with brainstem stimulation, could promote locomotor-like activity even when brainstem stimulation alone was ineffective.
• 3
  Direct chemical stimulation of propriospinal neurons in the cervical and/or thoracic region could induce locomotor-like activity in the lumbar region, even without brainstem stimulation or cord hemisections.