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Zhang Z, Su J, Tang J, Chung L, Page JC, Winter CC, Liu Y, Kegeles E, Conti S, Zhang Y, Biundo J, Chalif JI, Hua CY, Yang Z, Yao X, Yang Y, Chen S, Schwab JM, Wang KH, Chen C, Prerau MJ, He Z. Spinal projecting neurons in rostral ventromedial medulla co-regulate motor and sympathetic tone. Cell 2024; 187:3427-3444.e21. [PMID: 38733990 PMCID: PMC11193620 DOI: 10.1016/j.cell.2024.04.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 02/27/2024] [Accepted: 04/17/2024] [Indexed: 05/13/2024]
Abstract
Many behaviors require the coordinated actions of somatic and autonomic functions. However, the underlying mechanisms remain elusive. By opto-stimulating different populations of descending spinal projecting neurons (SPNs) in anesthetized mice, we show that stimulation of excitatory SPNs in the rostral ventromedial medulla (rVMM) resulted in a simultaneous increase in somatomotor and sympathetic activities. Conversely, opto-stimulation of rVMM inhibitory SPNs decreased both activities. Anatomically, these SPNs innervate both sympathetic preganglionic neurons and motor-related regions in the spinal cord. Fiber-photometry recording indicated that the activities of rVMM SPNs correlate with different levels of muscle and sympathetic tone during distinct arousal states. Inhibiting rVMM excitatory SPNs reduced basal muscle and sympathetic tone, impairing locomotion initiation and high-speed performance. In contrast, silencing the inhibitory population abolished muscle atonia and sympathetic hypoactivity during rapid eye movement (REM) sleep. Together, these results identify rVMM SPNs as descending spinal projecting pathways controlling the tone of both the somatomotor and sympathetic systems.
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Affiliation(s)
- Zicong Zhang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Junfeng Su
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Jing Tang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Leeyup Chung
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Jessica C Page
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Carla C Winter
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA; Harvard/MIT MD-PhD Program, Harvard Medical School, Boston, MA, USA
| | - Yuchu Liu
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Evgenii Kegeles
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA; PhD Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, USA
| | - Sara Conti
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Yu Zhang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Jason Biundo
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Joshua I Chalif
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, USA
| | - Charles Y Hua
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Zhiyun Yang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Xue Yao
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Yang Yang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Shuqiang Chen
- Graduate Program for Neuroscience, Boston University, Boston, MA, USA
| | - Jan M Schwab
- Belford Center for Spinal Cord Injury, The Ohio State University, Columbus, OH, USA; Departments of Neurology and Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Kuan Hong Wang
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, USA
| | - Chinfei Chen
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Michael J Prerau
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Zhigang He
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA; Department of Neurology and Ophthalmology, Harvard Medical School, Boston, MA, USA.
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2
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Ryczko D. The Mesencephalic Locomotor Region: Multiple Cell Types, Multiple Behavioral Roles, and Multiple Implications for Disease. Neuroscientist 2024; 30:347-366. [PMID: 36575956 PMCID: PMC11107129 DOI: 10.1177/10738584221139136] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The mesencephalic locomotor region (MLR) controls locomotion in vertebrates. In humans with Parkinson disease, locomotor deficits are increasingly associated with decreased activity in the MLR. This brainstem region, commonly considered to include the cuneiform and pedunculopontine nuclei, has been explored as a target for deep brain stimulation to improve locomotor function, but the results are variable, from modest to promising. However, the MLR is a heterogeneous structure, and identification of the best cell type to target is only beginning. Here, I review the studies that uncovered the role of genetically defined MLR cell types, and I highlight the cells whose activation improves locomotor function in animal models of Parkinson disease. The promising cell types to activate comprise some glutamatergic neurons in the cuneiform and caudal pedunculopontine nuclei, as well as some cholinergic neurons of the pedunculopontine nucleus. Activation of MLR GABAergic neurons should be avoided, since they stop locomotion or evoke bouts flanked with numerous stops. MLR is also considered a potential target in spinal cord injury, supranuclear palsy, primary progressive freezing of gait, or stroke. Better targeting of the MLR cell types should be achieved through optimized deep brain stimulation protocols, pharmacotherapy, or the development of optogenetics for human use.
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Affiliation(s)
- Dimitri Ryczko
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Canada
- Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Canada
- Neurosciences Sherbrooke, Sherbrooke, Canada
- Institut de Pharmacologie de Sherbrooke, Sherbrooke, Canada
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Scheuber MI, Guidolin C, Martins S, Sartori AM, Hofer AS, Schwab ME. Electrical stimulation of the cuneiform nucleus enhances the effects of rehabilitative training on locomotor recovery after incomplete spinal cord injury. Front Neurosci 2024; 18:1352742. [PMID: 38595973 PMCID: PMC11002271 DOI: 10.3389/fnins.2024.1352742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 03/13/2024] [Indexed: 04/11/2024] Open
Abstract
Most human spinal cord injuries are anatomically incomplete, leaving some fibers still connecting the brain with the sublesional spinal cord. Spared descending fibers of the brainstem motor control system can be activated by deep brain stimulation (DBS) of the cuneiform nucleus (CnF), a subnucleus of the mesencephalic locomotor region (MLR). The MLR is an evolutionarily highly conserved structure which initiates and controls locomotion in all vertebrates. Acute electrical stimulation experiments in female adult rats with incomplete spinal cord injury conducted in our lab showed that CnF-DBS was able to re-establish a high degree of locomotion five weeks after injury, even in animals with initially very severe functional deficits and white matter lesions up to 80-95%. Here, we analyzed whether CnF-DBS can be used to support medium-intensity locomotor training and long-term recovery in rats with large but incomplete spinal cord injuries. Rats underwent rehabilitative training sessions three times per week in an enriched environment, either with or without CnF-DBS supported hindlimb stepping. After 4 weeks, animals that trained under CnF-DBS showed a higher level of locomotor performance than rats that trained comparable distances under non-stimulated conditions. The MLR does not project to the spinal cord directly; one of its main output targets is the gigantocellular reticular nucleus in the medulla oblongata. Long-term electrical stimulation of spared reticulospinal fibers after incomplete spinal cord injury via the CnF could enhance reticulospinal anatomical rearrangement and in this way lead to persistent improvement of motor function. By analyzing the spared, BDA-labeled giganto-spinal fibers we found that their gray matter arborization density after discontinuation of CnF-DBS enhanced training was lower in the lumbar L2 and L5 spinal cord in stimulated as compared to unstimulated animals, suggesting improved pruning with stimulation-enhanced training. An on-going clinical study in chronic paraplegic patients investigates the effects of CnF-DBS on locomotor capacity.
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Affiliation(s)
- Myriam I. Scheuber
- Institute for Regenerative Medicine, University of Zurich, Schlieren, Switzerland
- ETH Phenomics Center, ETH Zurich, Zurich, Switzerland
| | - Carolina Guidolin
- Institute for Regenerative Medicine, University of Zurich, Schlieren, Switzerland
- ETH Phenomics Center, ETH Zurich, Zurich, Switzerland
| | - Suzi Martins
- Institute for Regenerative Medicine, University of Zurich, Schlieren, Switzerland
- ETH Phenomics Center, ETH Zurich, Zurich, Switzerland
| | - Andrea M. Sartori
- Institute for Regenerative Medicine, University of Zurich, Schlieren, Switzerland
- ETH Phenomics Center, ETH Zurich, Zurich, Switzerland
| | - Anna-Sophie Hofer
- Institute for Regenerative Medicine, University of Zurich, Schlieren, Switzerland
- ETH Phenomics Center, ETH Zurich, Zurich, Switzerland
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland
| | - Martin E. Schwab
- Institute for Regenerative Medicine, University of Zurich, Schlieren, Switzerland
- ETH Phenomics Center, ETH Zurich, Zurich, Switzerland
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Sharma S, Badenhorst CA, Ashby DM, Di Vito SA, Tran MA, Ghavasieh Z, Grewal GK, Belway CR, McGirr A, Whelan PJ. Inhibitory medial zona incerta pathway drives exploratory behavior by inhibiting glutamatergic cuneiform neurons. Nat Commun 2024; 15:1160. [PMID: 38326327 PMCID: PMC10850156 DOI: 10.1038/s41467-024-45288-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 01/19/2024] [Indexed: 02/09/2024] Open
Abstract
The cuneiform nucleus (CnF) regulates locomotor activity, which is canonically viewed as being primarily involved in initiating locomotion and regulating speed. Recent research shows greater context dependency in the locomotor functions of this nucleus. Glutamatergic neurons, which contain vesicular glutamate transporter 2 (vGLUT2), regulate context-dependent locomotor speed in the CnF and play a role in defensive behavior. Here, we identify projections from the medial zona incerta (mZI) to CnF vGLUT2 neurons that promote exploratory behavior. Using fiber photometry recordings in male mice, we find that mZI gamma-aminobutyric acid (GABA) neurons increase activity during periods of exploration. Activation of mZI GABAergic neurons is associated with reduced spiking of CnF neurons. Additionally, activating both retrogradely labeled mZI-CnF GABAergic projection neurons and their terminals in the CnF increase exploratory behavior. Inhibiting CnF vGLUT2 neuronal activity also increases exploratory behavior. These findings provide evidence for the context-dependent dynamic regulation of CnF vGLUT2 neurons, with the mZI-CnF circuit shaping exploratory behavior.
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Affiliation(s)
- Sandeep Sharma
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Cecilia A Badenhorst
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Donovan M Ashby
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
- Department of Psychiatry, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Stephanie A Di Vito
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Michelle A Tran
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Zahra Ghavasieh
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Gurleen K Grewal
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Cole R Belway
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Alexander McGirr
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
- Department of Psychiatry, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Patrick J Whelan
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada.
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.
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Morgenstern NA, Esposito MS. The Basal Ganglia and Mesencephalic Locomotor Region Connectivity Matrix. Curr Neuropharmacol 2024; 22:1454-1472. [PMID: 37559244 PMCID: PMC11097982 DOI: 10.2174/1570159x21666230809112840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 02/16/2023] [Accepted: 02/23/2023] [Indexed: 08/11/2023] Open
Abstract
Although classically considered a relay station for basal ganglia (BG) output, the anatomy, connectivity, and function of the mesencephalic locomotor region (MLR) were redefined during the last two decades. In striking opposition to what was initially thought, MLR and BG are actually reciprocally and intimately interconnected. New viral-based, optogenetic, and mapping technologies revealed that cholinergic, glutamatergic, and GABAergic neurons coexist in this structure, which, in addition to extending descending projections, send long-range ascending fibers to the BG. These MLR projections to the BG convey motor and non-motor information to specific synaptic targets throughout different nuclei. Moreover, MLR efferent fibers originate from precise neuronal subpopulations located in particular MLR subregions, defining independent anatomo-functional subcircuits involved in particular aspects of animal behavior such as fast locomotion, explorative locomotion, posture, forelimb- related movements, speed, reinforcement, among others. In this review, we revised the literature produced during the last decade linking MLR and BG. We conclude that the classic framework considering the MLR as a homogeneous output structure passively receiving input from the BG needs to be revisited. We propose instead that the multiple subcircuits embedded in this region should be taken as independent entities that convey relevant and specific ascending information to the BG and, thus, actively participate in the execution and tuning of behavior.
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Affiliation(s)
- Nicolás A. Morgenstern
- Champalimaud Research, Champalimaud Foundation, Lisbon, Portugal
- Faculty of Medicine, University of Lisbon, Instituto De Medicina Molecular João Lobo Antunes, Lisbon, Portugal
| | - Maria S. Esposito
- Department of Medical Physics, Centro Atomico Bariloche, CNEA, CONICET, Av. Bustillo 9500, San Carlos de Bariloche, Rio Negro, Argentina
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6
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Beebe NL, Herrera YN, Noftz WA, Roberts MT, Schofield BR. Characterization of three cholinergic inputs to the cochlear nucleus. J Chem Neuroanat 2023; 131:102284. [PMID: 37164181 PMCID: PMC10330717 DOI: 10.1016/j.jchemneu.2023.102284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/02/2023] [Accepted: 05/03/2023] [Indexed: 05/12/2023]
Abstract
Acetylcholine modulates responses throughout the auditory system, including at the earliest brain level, the cochlear nucleus (CN). Previous studies have shown multiple sources of cholinergic input to the CN but information about their relative contributions and the distribution of inputs from each source is lacking. Here, we used staining for cholinergic axons and boutons, retrograde tract tracing, and acetylcholine-selective anterograde tracing to characterize three sources of acetylcholine input to the CN in mice. Staining for cholinergic axons showed heavy cholinergic inputs to granule cell areas and the dorsal CN with lighter input to the ventral CN. Retrograde tract tracing revealed that cholinergic cells from the superior olivary complex, pontomesencephalic tegmentum, and lateral paragigantocellular nucleus send projections to the CN. When we selectively labeled cholinergic axons from each source to the CN, we found surprising similarities in their terminal distributions, with patterns that were overlapping rather than complementary. Each source heavily targeted granule cell areas and the dorsal CN (especially the deep dorsal CN) and sent light input into the ventral CN. Our results demonstrate convergence of cholinergic inputs from multiple sources in most regions of the CN and raise the possibility of convergence onto single CN cells. Linking sources of acetylcholine and their patterns of activity to modulation of specific cell types in the CN will be an important next step in understanding cholinergic modulation of early auditory processing.
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Affiliation(s)
- Nichole L Beebe
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Yoani N Herrera
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - William A Noftz
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Michael T Roberts
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Brett R Schofield
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, OH, USA.
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Dubuc R, Cabelguen JM, Ryczko D. Locomotor pattern generation and descending control: a historical perspective. J Neurophysiol 2023; 130:401-416. [PMID: 37465884 DOI: 10.1152/jn.00204.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 07/11/2023] [Accepted: 07/12/2023] [Indexed: 07/20/2023] Open
Abstract
The ability to generate and control locomotor movements depends on complex interactions between many areas of the nervous system, the musculoskeletal system, and the environment. How the nervous system manages to accomplish this task has been the subject of investigation for more than a century. In vertebrates, locomotion is generated by neural networks located in the spinal cord referred to as central pattern generators. Descending inputs from the brain stem initiate, maintain, and stop locomotion as well as control speed and direction. Sensory inputs adapt locomotor programs to the environmental conditions. This review presents a comparative and historical overview of some of the neural mechanisms underlying the control of locomotion in vertebrates. We have put an emphasis on spinal mechanisms and descending control.
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Affiliation(s)
- Réjean Dubuc
- Groupe de Recherche en Activité Physique Adaptée, Département des Sciences de l'Activité Physique, Université du Québec à Montréal, Montreal, Quebec, Canada
- Groupe de Recherche sur le Système Nerveux Central, Département de Neurosciences, Université de Montréal, Montreal, Quebec, Canada
| | - Jean-Marie Cabelguen
- Institut National de la Santé et de la Recherche Médicale (INSERM) U 1215-Neurocentre Magendie, Université de Bordeaux, Bordeaux Cedex, France
| | - Dimitri Ryczko
- Département de Pharmacologie-Physiologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada
- Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada
- Neurosciences Sherbrooke, Sherbrooke, Quebec, Canada
- Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada
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Lacroix-Ouellette P, Dubuc R. Brainstem neural mechanisms controlling locomotion with special reference to basal vertebrates. Front Neural Circuits 2023; 17:910207. [PMID: 37063386 PMCID: PMC10098025 DOI: 10.3389/fncir.2023.910207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 03/13/2023] [Indexed: 04/03/2023] Open
Abstract
Over the last 60 years, the basic neural circuitry responsible for the supraspinal control of locomotion has progressively been uncovered. Initially, significant progress was made in identifying the different supraspinal structures controlling locomotion in mammals as well as some of the underlying mechanisms. It became clear, however, that the complexity of the mammalian central nervous system (CNS) prevented researchers from characterizing the detailed cellular mechanisms involved and that animal models with a simpler nervous system were needed. Basal vertebrate species such as lampreys, xenopus embryos, and zebrafish became models of choice. More recently, optogenetic approaches have considerably revived interest in mammalian models. The mesencephalic locomotor region (MLR) is an important brainstem region known to control locomotion in all vertebrate species examined to date. It controls locomotion through intermediary cells in the hindbrain, the reticulospinal neurons (RSNs). The MLR comprises populations of cholinergic and glutamatergic neurons and their specific contribution to the control of locomotion is not fully resolved yet. Moreover, the downward projections from the MLR to RSNs is still not fully understood. Reporting on discoveries made in different animal models, this review article focuses on the MLR, its projections to RSNs, and the contribution of these neural elements to the control of locomotion. Excellent and detailed reviews on the brainstem control of locomotion have been recently published with emphasis on mammalian species. The present review article focuses on findings made in basal vertebrates such as the lamprey, to help direct new research in mammals, including humans.
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Affiliation(s)
| | - Réjean Dubuc
- Department of Neurosciences, Université de Montréal, Montréal, QC, Canada
- Department of Physical Activity Sciences, Université du Québec à Montréal, Montréal, QC, Canada
- Research Group for Adapted Physical Activity, Université du Québec à Montréal, Montréal, QC, Canada
- *Correspondence: Réjean Dubuc,
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Wagner V, Knudsen MS, Curtis DJ, Riberholt CG. Use of the EXOPULSE Mollii for severe ataxia in an adult male 4 months after cardiac arrest. BMJ Case Rep 2023; 16:e249574. [PMID: 36963762 PMCID: PMC10040057 DOI: 10.1136/bcr-2022-249574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023] Open
Abstract
The EXOPULSE Mollii is designed to reduce spasticity through low-current electrical stimulation of major muscle groups. The effect on severe cerebellar ataxia has not been investigated. This case describes the use of the EXOPULSE Mollii in an adult male with severe cerebellar ataxia 4 months after cardiac arrest and ischaemic stroke. The patient used the suit in 15 of 19 possible sessions (78.9%). He improved in the sit-to-stand test, arm function test and 10 m walking test. He described improved visual focus, ability to speak and swallow. Improvements were maintained for 1 week after the last session. The EXOPULSE Mollii is relevant to consider in the early stages of inpatient rehabilitation for patients with severe ataxia, but further research is warranted.
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Affiliation(s)
- Vibeke Wagner
- Department of Neurorehabilitation TBI Unit, Rigshospitalet, Hvidovre, Denmark
| | | | - Derek John Curtis
- Child and Youth Administration, City of Copenhagen, Copenhagen, Denmark
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