Ipsilateral inspiratory intercostal muscle activity after C2 spinal cord hemisection in rats
Open Access
- 26 November 2013
- journal article
- Published by Informa UK Limited in The Journal of Spinal Cord Medicine
- Vol. 38 (2), 224-230
- https://doi.org/10.1179/2045772314y.0000000220
Abstract
Upper cervical spinal cord hemisection causes paralysis of the ipsilateral hemidiaphragm; however, the effect of C2 hemisection on the function of the intercostal muscles is not clear. We hypothesized that C2 hemisection would eliminate inspiratory intercostal activity ipsilateral to the injury and that some activity would return in a time-dependent manner. Female Sprague Dawley rats were anesthetized with urethane and inspiratory intercostal electromyogram (EMG) activity was recorded in control rats, acutely injured C2 hemisected rats, and at 1 and 16 weeks post C2 hemisection. Bilateral recordings of intercostal EMG activity showed that inspiratory activity was reduced immediately after injury and increased over time. EMG activity was observed first in rostral spaces followed by recovery occurring in caudal spaces. Theophylline increased respiratory drive and increased intercostal activity, inducing activity that was previously absent. These results suggest that there are crossed, initially latent, respiratory connections to neurons innervating the intercostal muscles similar to those innervating phrenic motor neurons.Keywords
This publication has 33 references indexed in Scilit:
- Contribution of the spontaneous crossed-phrenic phenomenon to inspiratory tidal volume in spontaneously breathing ratsJournal of Applied Physiology, 2012
- Electrophysiological and Morphological Characterization of Propriospinal Interneurons in the Thoracic Spinal CordJournal of Neurophysiology, 2011
- Influence of vagal afferents on supraspinal and spinal respiratory activity following cervical spinal cord injury in ratsJournal of Applied Physiology, 2010
- Intercostal muscle pacing with high frequency spinal cord stimulation in dogsRespiratory Physiology & Neurobiology, 2010
- Spinal circuitry and respiratory recovery following spinal cord injuryRespiratory Physiology & Neurobiology, 2009
- The crossed phrenic phenomenon and recovery of function following spinal cord injuryRespiratory Physiology & Neurobiology, 2009
- Respiratory neuroplasticity and cervical spinal cord injury: translational perspectivesTrends in Neurosciences, 2008
- Spinal activation of the cAMP-PKA pathway induces respiratory motor recovery following high cervical spinal cord injuryBrain Research, 2008
- Modest spontaneous recovery of ventilation following chronic high cervical hemisection in ratsExperimental Neurology, 2008
- GABA, not glycine, mediates inhibition of latent respiratory motor pathways after spinal cord injuryExperimental Neurology, 2007