title: Rostro-caudal inhibition of hindlimb movements in the spinal cord of mice.
abstract: Inhibitory neurons in the adult mammalian spinal cord are known to locally modulate afferent feedback--from muscle proprioceptors and from skin receptors--to pattern motor activity for locomotion and postural control. Here, using optogenetic tools, we explored how the same population of inhibitory interneurons globally affects hindlimb movements in the spinal cord of both anesthetized and freely moving mice. Activation of inhibitory interneurons up to the middle/lower spinal cord i.e. T8-T9, were able to completely and globally suppress all ipsilateral hindlimb movements. Furthermore, the same population of interneurons--which inhibited movements--did not significantly change the sensory and proprioceptive information from the affected limbs to the cortex. These results suggest a rostro-caudal organization of inhibition in the spinal cord motor output without modulation of ascending sensory pathways.
authors: McGovern Institute for Brain Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, United States of America.
authors: Vittorio
authors: V
authors: Caggiano
authors: Picower Institute for Learning and Memory, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, United States of America.
authors: Mirganka
authors: M
authors: Sur
authors: McGovern Institute for Brain Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, United States of America.
authors: Emilio
authors: E
authors: Bizzi
mesh_terms: D000344:Afferent Pathways; D000818:Animals; D002478:Cells, Cultured; D000075402:Channelrhodopsins; D004558:Electric Stimulation; D006614:Hindlimb / Q000502:physiology*; D007124:Immunoenzyme Techniques; D007395:Interneurons / Q000166:cytology / Q000502:physiology*; D008124:Locomotion / Q000502:physiology*; D051379:Mice; D009415:Nerve Net / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology*; D013116:Spinal Cord / Q000166:cytology / Q000502:physiology*; D009435:Synaptic Transmission; D050495:Vesicular Inhibitory Amino Acid Transport Proteins / Q000502:physiology
chemical_list: D000075402:Channelrhodopsins; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; C492244:Viaat protein, mouse