title: Utility of intracerebral theta burst electrical stimulation to attenuate interhemispheric inhibition and to promote motor recovery after cortical injury in an animal model.
abstract: Following a cerebral cortex injury such as stroke, excessive inhibition around the core of the injury is thought to reduce the potential for new motor learning. In part, this may be caused by an imbalance of interhemispheric inhibition (IHI); therefore, treatments that relieve the inhibitory drive from the healthy hemisphere to the peri-lesional area may enhance motor recovery. Theta burst stimulation delivered by transcranial magnetic stimulation has been tested as a means of normalizing IHI, but clinical results have been variable. Here we use a new rat model of synaptic IHI to demonstrate that electrical intracranial theta burst stimulation causes long-lasting changes in motor cortex excitability. Further, we show that contralateral intermittent theta burst stimulation (iTBS) blocks IHI via a mechanism involving cannabinoid receptors. Finally, we show that contralesional iTBS applied during recovery from cortical injury in rats improves the recovery of motor function. These findings suggest that theta burst stimulation delivered through implanted electrodes may be a promising avenue to explore for augmenting rehabilitation from brain injury.
authors.affiliation: Department of Anatomy and the Brain Health Research Centre, University of Otago, PO Box 913, Dunedin 9054, New Zealand.
authors.forename: Melissa D
authors.initials: MD
authors.lastname: Barry
authors.affiliation: Department of Anatomy and the Brain Health Research Centre, University of Otago, PO Box 913, Dunedin 9054, New Zealand.
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Boddington
authors.affiliation: Department of Anatomy and the Brain Health Research Centre, University of Otago, PO Box 913, Dunedin 9054, New Zealand.
authors.forename: Kajsa M
authors.initials: KM
authors.lastname: Igelström
authors.affiliation: Department of Anatomy and the Brain Health Research Centre, University of Otago, PO Box 913, Dunedin 9054, New Zealand.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Gray
authors.affiliation: School of Physical Education and the Brain Health Research Centre, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
authors.forename: Jon
authors.initials: J
authors.lastname: Shemmell
authors.affiliation: Department of Cellular & Molecular Pharmacology, The Chicago Medical School, Rosalind Franklin University of Medicine & Science, North Chicago, IL 60064-3037, USA.
authors.forename: Kuei Y
authors.initials: KY
authors.lastname: Tseng
authors.affiliation: Department of Anatomy and the Brain Health Research Centre, University of Otago, PO Box 913, Dunedin 9054, New Zealand.
authors.forename: Dorothy E
authors.initials: DE
authors.lastname: Oorschot
authors.affiliation: Department of Anatomy and the Brain Health Research Centre, University of Otago, PO Box 913, Dunedin 9054, New Zealand. Electronic address: john.reynolds@otago.ac.nz.
authors.forename: John N J
authors.initials: JN
authors.lastname: Reynolds
mesh_terms: D000818:Animals; D001703:Biophysics; D001930:Brain Injuries / Q000150:complications / Q000473:pathology; D004195:Disease Models, Animal; D004569:Electroencephalography; D007839:Functional Laterality / Q000502:physiology*; D008297:Male; D008564:Membrane Potentials; D009044:Motor Cortex / Q000473:pathology* / Q000502:physiology; D009069:Movement Disorders / Q000209:etiology / Q000628:therapy*; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D010880:Piperidines / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D020127:Recovery of Function / Q000502:physiology*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*
chemical_list: D010880:Piperidines; D011720:Pyrazoles; C103505:AM 251
keywords: Electrical stimulation; Interhemispheric inhibition; Motor cortex; Rehabilitation; Stroke; Theta burst stimulation