title: Cortical stimulation causes long-term changes in H-reflexes and spinal motoneuron GABA receptors.
abstract: The cortex gradually modifies the spinal cord during development, throughout later life, and in response to trauma or disease. The mechanisms of this essential function are not well understood. In this study, weak electrical stimulation of rat sensorimotor cortex increased the soleus H-reflex, increased the numbers and sizes of GABAergic spinal interneurons and GABAergic terminals on soleus motoneurons, and decreased GABA(A) and GABA(B) receptor labeling in these motoneurons. Several months after the stimulation ended the interneuron and terminal increases had disappeared, but the H-reflex increase and the receptor decreases remained. The changes in GABAergic terminals and GABA(B) receptors accurately predicted the changes in H-reflex size. The results reveal a new long-term dimension to cortical-spinal interactions and raise new therapeutic possibilities.
authors.affiliation: Laboratory of Neural Injury and Repair, Wadsworth Center, New York State Department of Health and State University of New York, Albany, New York 12201-0509, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.forename: Lu
authors.initials: L
authors.lastname: Chen
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Wolpaw
authors.forename: Xiang Yang
authors.initials: XY
authors.lastname: Chen
mesh_terms: D000818:Animals; D004558:Electric Stimulation; D019054:Evoked Potentials, Motor; D059330:GABAergic Neurons / Q000502:physiology; D015870:Gene Expression; D007395:Interneurons / Q000502:physiology; D008297:Male; D009044:Motor Cortex / Q000502:physiology; D009046:Motor Neurons / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology; D009469:Neuromuscular Junction / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000235:genetics / Q000378:metabolism*; D018080:Receptors, GABA-B / Q000235:genetics / Q000378:metabolism*; D012018:Reflex; D013003:Somatosensory Cortex / Q000502:physiology; D013116:Spinal Cord / Q000502:physiology*
chemical_list: D011963:Receptors, GABA-A; D018080:Receptors, GABA-B