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Chaudhary R, Singh R. Therapeutic Viewpoint on Rat Models of Locomotion Abnormalities and Neurobiological Indicators in Parkinson's Disease. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2024; 23:488-503. [PMID: 37202886 DOI: 10.2174/1871527322666230518111323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 11/11/2022] [Accepted: 12/02/2022] [Indexed: 05/20/2023]
Abstract
BACKGROUND Locomotion problems in Parkinson's syndrome are still a research and treatment difficulty. With the recent introduction of brain stimulation or neuromodulation equipment that is sufficient to monitor activity in the brain using electrodes placed on the scalp, new locomotion investigations in patients having the capacity to move freely have sprung up. OBJECTIVE This study aimed to find rat models and locomotion-connected neuronal indicators and use them all over a closed-loop system to enhance the future and present treatment options available for Parkinson's disease. METHODS Various publications on locomotor abnormalities, Parkinson's disease, animal models, and other topics have been searched using several search engines, such as Google Scholar, Web of Science, Research Gate, and PubMed. RESULTS Based on the literature, we can conclude that animal models are used for further investigating the locomotion connectivity deficiencies of many biological measuring devices and attempting to address unanswered concerns from clinical and non-clinical research. However, translational validity is required for rat models to contribute to the improvement of upcoming neurostimulation-based medicines. This review discusses the most successful methods for modelling Parkinson's locomotion in rats. CONCLUSION This review article has examined how scientific clinical experiments lead to localised central nervous system injuries in rats, as well as how the associated motor deficits and connection oscillations reflect this. This evolutionary process of therapeutic interventions may help to improve locomotion- based treatment and management of Parkinson's syndrome in the upcoming years.
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Affiliation(s)
- Rishabh Chaudhary
- Department of Pharmacology, Central University of Punjab, Bathinda 151401, India
- Department of Pharmacology, M.M. College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, Haryana 133207, India
| | - Randhir Singh
- Department of Pharmacology, Central University of Punjab, Bathinda 151401, India
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2
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Joza S, Camicioli R, Martin WRW, Wieler M, Gee M, Ba F. Pedunculopontine Nucleus Dysconnectivity Correlates With Gait Impairment in Parkinson’s Disease: An Exploratory Study. Front Aging Neurosci 2022; 14:874692. [PMID: 35875799 PMCID: PMC9304714 DOI: 10.3389/fnagi.2022.874692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022] Open
Abstract
Background Gait impairment is a debilitating and progressive feature of Parkinson’s disease (PD). Increasing evidence suggests that gait control is partly mediated by cholinergic signaling from the pedunculopontine nucleus (PPN). Objective We investigated whether PPN structural connectivity correlated with quantitative gait measures in PD. Methods Twenty PD patients and 15 controls underwent diffusion tensor imaging to quantify structural connectivity of the PPN. Whole brain analysis using tract-based spatial statistics and probabilistic tractography were performed using the PPN as a seed region of interest for cortical and subcortical target structures. Gait metrics were recorded in subjects’ medication ON and OFF states, and were used to determine if specific features of gait dysfunction in PD were related to PPN structural connectivity. Results Tract-based spatial statistics revealed reduced structural connectivity involving the corpus callosum and right superior corona radiata, but did not correlate with gait measures. Abnormalities in PPN structural connectivity in PD were lateralized to the right hemisphere, with pathways involving the right caudate nucleus, amygdala, pre-supplementary motor area, and primary somatosensory cortex. Altered connectivity of the right PPN-caudate nucleus was associated with worsened cadence, stride time, and velocity while in the ON state; altered connectivity of the right PPN-amygdala was associated with reduced stride length in the OFF state. Conclusion Our exploratory analysis detects a potential correlation between gait dysfunction in PD and a characteristic pattern of connectivity deficits in the PPN network involving the right caudate nucleus and amygdala, which may be investigated in future larger studies.
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Affiliation(s)
- Stephen Joza
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Richard Camicioli
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | | | - Marguerite Wieler
- Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, AB, Canada
| | - Myrlene Gee
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Fang Ba
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
- *Correspondence: Fang Ba,
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Levodopa affects spike and local field synchronisation in the pedunculopontine nucleus of a rat model of Parkinson's disease. Aging (Albany NY) 2021; 13:7314-7329. [PMID: 33639616 PMCID: PMC7993725 DOI: 10.18632/aging.202585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 01/04/2021] [Indexed: 11/25/2022]
Abstract
The pedunculopontine nucleus (PPN) undergoes significant anatomic and electrophysiological alterations in Parkinson’s disease (PD), severely impacting locomotion. However, the effect of 6-hydroxydopamine (6-OHDA) lesion and levodopa (L-DOPA) therapy on the relationships between spike activities and local field potential (LFP) within the PPN is not well-understood. Synchronisation between the spike activity of individual neurones and LFP of neuronal ensembles is a crucial problem in the pathogenesis of PD. In this study, LFP signals and spikes in the PPN of rats in control, lesioned, and L-DOPA groups were recorded synchronously with a multi-unit electrical signal acquisition system and analysed for their coherence value, spike-field coherence, and phase-lock relationship. The spike-LFP relationship in the PPN was markedly increased in specific frequency bands because of the 6-OHDA lesion but differed depending on the animal locomotion state and neuronal type. L-DOPA had a limited therapeutic effect on the 6-OHDA-induced increase in the coherence value. Our study demonstrates that the PPN spike-LFP relationship is involved in the pathogenesis of PD and is critical for the effects of L-DOPA, providing a basis for the clinical treatment of refractory PD symptoms.
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Wang X, Geng X, Li M, Xie J, Chen D, Han H, Meng X, Yao X, Zhang H, Gao Y, Chang H, Zhang X, Wang Y, Wang M. Electrophysiological and Neurochemical Considerations of Distinct Neuronal Populations in the Rat Pedunculopontine Nucleus and Their Responsiveness Following 6-Hydroxydopamine Lesions. Front Neurosci 2019; 13:1034. [PMID: 31616246 PMCID: PMC6775246 DOI: 10.3389/fnins.2019.01034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 09/12/2019] [Indexed: 12/30/2022] Open
Abstract
The pedunculopontine nucleus (PPN) is composed of a morphologically and neurochemically heterogeneous population of neurons, which is severely affected by Parkinson’s disease (PD). However, the role of each subtype of neurons within the PPN in the pathophysiology of PD has not been completely elucidated. In this study, we present the discharge profiles of three classified subtypes of PPN neurons and their alterations after 6-hydroxydopamine (6-OHDA) lesion. Following 6-OHDA lesion, the spike timing of the Type II (GABAergic) and Type III (glutamatergic) neurons had phase-lock with the oscillations in the delta and beta band frequency range in the PPN, respectively. Morphological evidence has shown distinct alteration in three kinds of neurons after 6-OHDA lesion. These findings revealed that the changes in the firing characteristics of neurons in PPN in hemi-parkinsonism rats are closely associated with damaged neuronal morphology, which would make contributions to the divergence of dysfunctions in Parkinsonism.
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Affiliation(s)
- Xuenan Wang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Xiwen Geng
- Experimental Center, Shandong University of Traditional Chinese Medicine, Jinan, China.,Advanced Material Genome Innovation Team, Advanced Materials Institute, Shandong Academy of Sciences, Qilu University of Technology, Jinan, China
| | - Min Li
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Jinlu Xie
- Department of Physiology, School of Medical Huzhou University, Huzhou Central Hospital, Huzhou, China
| | - Dadian Chen
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Hongyu Han
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Xiaoqian Meng
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Xiaomeng Yao
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China.,School of Nursing, Qilu Institute of Technology, Jinan, China
| | - Haiyan Zhang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Yunfeng Gao
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Hongli Chang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Xiao Zhang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Yanan Wang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Min Wang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
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Gut NK, Mena-Segovia J. Dichotomy between motor and cognitive functions of midbrain cholinergic neurons. Neurobiol Dis 2019; 128:59-66. [PMID: 30213733 PMCID: PMC7176324 DOI: 10.1016/j.nbd.2018.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 07/18/2018] [Accepted: 09/09/2018] [Indexed: 12/15/2022] Open
Abstract
Cholinergic neurons of the pedunculopontine nucleus (PPN) are interconnected with all the basal ganglia structures, as well as with motor centers in the brainstem and medulla. Recent theories put into question whether PPN cholinergic neurons form part of a locomotor region that directly regulates the motor output, and rather suggest a modulatory role in adaptive behavior involving both motor and cognitive functions. In support of this, experimental studies in animals suggest that cholinergic neurons reinforce actions by signaling reward prediction and shape adaptations in behavior during changes of environmental contingencies. This is further supported by clinical studies proposing that decreased cholinergic transmission originated in the PPN is associated with impaired sensorimotor integration and perseverant behavior, giving rise to some of the symptoms observed in Parkinson's disease and progressive supranuclear palsy. Altogether, the evidence suggests that cholinergic neurons of the PPN, mainly through their interactions with the basal ganglia, have a leading role in action control.
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Affiliation(s)
- Nadine K Gut
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, NJ, USA
| | - Juan Mena-Segovia
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, NJ, USA.
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6
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Geng X, Wang X, He F, Zhang X, Xie J, Gao G, Han H, Yao X, Zhang H, Gao Y, Wang Y, Wang M. Spike and Local Field Synchronization Between the Pedunculopontine Nucleus and Primary Motor Cortex in a Rat Model of Parkinson's Disease. Neuroscience 2019; 404:470-483. [DOI: 10.1016/j.neuroscience.2019.01.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 10/16/2018] [Accepted: 01/23/2019] [Indexed: 02/06/2023]
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7
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State-Dependent Spike and Local Field Synchronization between the Thalamic Parafascicular Nucleus and the Dorsal Striatum in a Rat Model of Parkinson's Disease. Neuroscience 2019; 404:27-38. [DOI: 10.1016/j.neuroscience.2019.01.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/26/2019] [Accepted: 01/28/2019] [Indexed: 01/29/2023]
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The pedunclopontine nucleus and Parkinson's disease. Neurobiol Dis 2018; 128:3-8. [PMID: 30171892 DOI: 10.1016/j.nbd.2018.08.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 06/22/2018] [Accepted: 08/26/2018] [Indexed: 01/08/2023] Open
Abstract
In the last decade, scientific and clinical interest in the pedunculopontine nucleus (PPN) has grown dramatically. This growth is largely a consequence of experimental work demonstrating its connection to the control of gait and of clinical work implicating PPN pathology in levodopa-insensitive gait symptoms of Parkinson's disease (PD). In addition, the development of optogenetic and chemogenetic approaches has made experimental analysis of PPN circuitry and function more tractable. In this brief review, recent findings in the field linking PPN to the basal ganglia and PD are summarized; in addition, an attempt is made to identify key gaps in our understanding and challenges this field faces in moving forward.
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Di Giovanni G, Chagraoui A, Puginier E, Galati S, De Deurwaerdère P. Reciprocal interaction between monoaminergic systems and the pedunculopontine nucleus: Implication in the mechanism of L-DOPA. Neurobiol Dis 2018; 128:9-18. [PMID: 30149181 DOI: 10.1016/j.nbd.2018.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/19/2018] [Accepted: 08/23/2018] [Indexed: 01/31/2023] Open
Abstract
The pedunculopontine nucleus (PPN) is part of the mesencephalic locomotor region (MLR) and has been involved in the control of gait, posture, locomotion, sleep, and arousal. It likely participates in some motor and non-motor symptoms of Parkinson's disease and is regularly proposed as a surgical target to ameliorate gait, posture and sleep disorders in Parkinsonian patients. The PPN overlaps with the monoaminergic systems including dopamine, serotonin and noradrenaline in the modulation of the above-mentioned functions. All these systems are involved in Parkinson's disease and the mechanism of the anti-Parkinsonian agents, mostly L-DOPA. This suggests that PPN interacts with monoaminergic neurons and vice versa. Some evidence indicates that the PPN sends cholinergic, glutamatergic and even gabaergic inputs to mesencephalic dopaminergic cells, with the data regarding serotonergic or noradrenergic cells being less well known. Similarly, the control exerted by the PPN on dopaminergic neurons, is multiple and complex, and more extensively explored than the other monoaminergic systems. The data on the influence of monoaminergic systems on PPN neuron activity are rather scarce. While there is evidence that the PPN influences the therapeutic response of L-DOPA, it is still difficult to discerne the reciprocal action of the PPN and monoaminergic systems in this action. Additional data are required to better understand the functional organization of monoaminergic inputs to the MLR including the PPN to get a clearer picture of their interaction.
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Affiliation(s)
- Giuseppe Di Giovanni
- Department of Physiology & Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, UK.
| | - Abdeslam Chagraoui
- Normandie Univ, UNIROUEN, INSERM, U1239, CHU Rouen, Neuronal and Neuroendocrine Differentiation and Communication Laboratory, Institute for Research and Innovation in Biomedicine of Normandy (IRIB), Rouen, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France
| | - Emilie Puginier
- Normandie Univ, UNIROUEN, INSERM, U1239, CHU Rouen, Neuronal and Neuroendocrine Differentiation and Communication Laboratory, Institute for Research and Innovation in Biomedicine of Normandy (IRIB), Rouen, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France
| | - Salvatore Galati
- Parkinson and movement Disorders Center Neurocenter of Southern Switzerland, Ospedale Civico di Lugano, Lugano, Switzerland
| | - Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique (Unité Mixte de Recherche 5287), 146 rue Léo Saignat, B.P.281, F-33000 Bordeaux Cedex, France.
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French IT, Muthusamy KA. A Review of the Pedunculopontine Nucleus in Parkinson's Disease. Front Aging Neurosci 2018; 10:99. [PMID: 29755338 PMCID: PMC5933166 DOI: 10.3389/fnagi.2018.00099] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 03/22/2018] [Indexed: 01/04/2023] Open
Abstract
The pedunculopontine nucleus (PPN) is situated in the upper pons in the dorsolateral portion of the ponto-mesencephalic tegmentum. Its main mass is positioned at the trochlear nucleus level, and is part of the mesenphalic locomotor region (MLR) in the upper brainstem. The human PPN is divided into two subnuclei, the pars compacta (PPNc) and pars dissipatus (PPNd), and constitutes both cholinergic and non-cholinergic neurons with afferent and efferent projections to the cerebral cortex, thalamus, basal ganglia (BG), cerebellum, and spinal cord. The BG controls locomotion and posture via GABAergic output of the substantia nigra pars reticulate (SNr). In PD patients, GABAergic BG output levels are abnormally increased, and gait disturbances are produced via abnormal increases in SNr-induced inhibition of the MLR. Since the PPN is vastly connected with the BG and the brainstem, dysfunction within these systems lead to advanced symptomatic progression in Parkinson's disease (PD), including sleep and cognitive issues. To date, the best treatment is to perform deep brain stimulation (DBS) on PD patients as outcomes have shown positive effects in ameliorating the debilitating symptoms of this disease by treating pathological circuitries within the parkinsonian brain. It is therefore important to address the challenges and develop this procedure to improve the quality of life of PD patients.
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Affiliation(s)
- Isobel T. French
- Division of Neurosurgery, Department of Surgery, University Malaya, Kuala Lumpur, Malaysia
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A Neural Circuit Mechanism for the Involvements of Dopamine in Effort-Related Choices: Decay of Learned Values, Secondary Effects of Depletion, and Calculation of Temporal Difference Error. eNeuro 2018; 5:eN-NWR-0021-18. [PMID: 29468191 PMCID: PMC5820541 DOI: 10.1523/eneuro.0021-18.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 01/11/2018] [Indexed: 12/17/2022] Open
Abstract
Dopamine has been suggested to be crucially involved in effort-related choices. Key findings are that dopamine depletion (i) changed preference for a high-cost, large-reward option to a low-cost, small-reward option, (ii) but not when the large-reward option was also low-cost or the small-reward option gave no reward, (iii) while increasing the latency in all the cases but only transiently, and (iv) that antagonism of either dopamine D1 or D2 receptors also specifically impaired selection of the high-cost, large-reward option. The underlying neural circuit mechanisms remain unclear. Here we show that findings i–iii can be explained by the dopaminergic representation of temporal-difference reward-prediction error (TD-RPE), whose mechanisms have now become clarified, if (1) the synaptic strengths storing the values of actions mildly decay in time and (2) the obtained-reward-representing excitatory input to dopamine neurons increases after dopamine depletion. The former is potentially caused by background neural activity–induced weak synaptic plasticity, and the latter is assumed to occur through post-depletion increase of neural activity in the pedunculopontine nucleus, where neurons representing obtained reward exist and presumably send excitatory projections to dopamine neurons. We further show that finding iv, which is nontrivial given the suggested distinct functions of the D1 and D2 corticostriatal pathways, can also be explained if we additionally assume a proposed mechanism of TD-RPE calculation, in which the D1 and D2 pathways encode the values of actions with a temporal difference. These results suggest a possible circuit mechanism for the involvements of dopamine in effort-related choices and, simultaneously, provide implications for the mechanisms of TD-RPE calculation.
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12
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Geng X, Wang X, Xie J, Zhang X, Wang X, Hou Y, Lei C, Li M, Han H, Yao X, Zhang Q, Wang M. Effect of l-DOPA on local field potential relationship between the pedunculopontine nucleus and primary motor cortex in a rat model of Parkinson’s disease. Behav Brain Res 2016; 315:1-9. [DOI: 10.1016/j.bbr.2016.08.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 08/06/2016] [Accepted: 08/07/2016] [Indexed: 01/07/2023]
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13
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Baizabal-Carvallo JF, Alonso-Juarez M. Low-frequency deep brain stimulation for movement disorders. Parkinsonism Relat Disord 2016; 31:14-22. [DOI: 10.1016/j.parkreldis.2016.07.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 07/21/2016] [Accepted: 07/28/2016] [Indexed: 12/24/2022]
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De Deurwaerdère P, Di Giovanni G, Millan MJ. Expanding the repertoire of L-DOPA's actions: A comprehensive review of its functional neurochemistry. Prog Neurobiol 2016; 151:57-100. [PMID: 27389773 DOI: 10.1016/j.pneurobio.2016.07.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/18/2016] [Accepted: 07/03/2016] [Indexed: 01/11/2023]
Abstract
Though a multi-facetted disorder, Parkinson's disease is prototypically characterized by neurodegeneration of nigrostriatal dopaminergic neurons of the substantia nigra pars compacta, leading to a severe disruption of motor function. Accordingly, L-DOPA, the metabolic precursor of dopamine (DA), is well-established as a treatment for the motor deficits of Parkinson's disease despite long-term complications such as dyskinesia and psychiatric side-effects. Paradoxically, however, despite the traditional assumption that L-DOPA is transformed in residual striatal dopaminergic neurons into DA, the mechanism of action of L-DOPA is neither simple nor entirely clear. Herein, focussing on its influence upon extracellular DA and other neuromodulators in intact animals and experimental models of Parkinson's disease, we highlight effects other than striatal generation of DA in the functional profile of L-DOPA. While not excluding a minor role for glial cells, L-DOPA is principally transformed into DA in neurons yet, interestingly, with a more important role for serotonergic than dopaminergic projections. Moreover, in addition to the striatum, L-DOPA evokes marked increases in extracellular DA in frontal cortex, nucleus accumbens, the subthalamic nucleus and additional extra-striatal regions. In considering its functional profile, it is also important to bear in mind the marked (probably indirect) influence of L-DOPA upon cholinergic, GABAergic and glutamatergic neurons in the basal ganglia and/or cortex, while anomalous serotonergic transmission is incriminated in the emergence of L-DOPA elicited dyskinesia and psychosis. Finally, L-DOPA may exert intrinsic receptor-mediated actions independently of DA neurotransmission and can be processed into bioactive metabolites. In conclusion, L-DOPA exerts a surprisingly complex pattern of neurochemical effects of much greater scope that mere striatal transformation into DA in spared dopaminergic neurons. Their further experimental and clinical clarification should help improve both L-DOPA-based and novel strategies for controlling the motor and other symptoms of Parkinson's disease.
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Affiliation(s)
- Philippe De Deurwaerdère
- CNRS (Centre National de la Recherche Scientifique), Institut des Maladies Neurodégénératives, UMR CNRS 5293, F-33000 Bordeaux, France.
| | - Giuseppe Di Giovanni
- Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, UK; Department of Physiology & Biochemistry, Faculty of Medicine and Surgery, University of Malta, Malta
| | - Mark J Millan
- Institut de Recherche Servier, Pole for Therapeutic Innovation in Neuropsychiatry, 78290 Croissy/Seine,Paris, France
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Li M, Zhou M, Wen P, Wang Q, Yang Y, Xiao H, Xie Z, Li X, Wang N, Wang J, Luo F, Chang J, Zhang W. The network of causal interactions for beta oscillations in the pedunculopontine nucleus, primary motor cortex, and subthalamic nucleus of walking parkinsonian rats. Exp Neurol 2016; 282:27-36. [PMID: 27163550 DOI: 10.1016/j.expneurol.2016.05.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 03/20/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
Abstract
Oscillatory activity has been well-studied in many structures within cortico-basal ganglia circuits, but it is not well understood within the pedunculopontine nucleus (PPN), which was recently introduced as a potential target for the treatment of gait and postural impairments in advanced stages of Parkinson's disease (PD). To investigate oscillatory activity in the PPN and its relationship with oscillatory activity in cortico-basal ganglia circuits, we simultaneously recorded local field potentials in the PPN, primary motor cortex (M1), and subthalamic nucleus (STN) of 6-hydroxydopamine (6-OHDA)-induced hemiparkinsonian rats during resting and walking. After analysis of power spectral density, coherence, and partial Granger causality, three major findings emerged: 1) after 6-OHDA lesions, beta band oscillations were enhanced in all three regions during walking; 2) the direction of information flow for beta oscillations among the three structures was STN→M1, STN→PPN, and PPN→M1; 3) after the treatment of levodopa, beta activity in the three regions was reduced significantly and the flow of beta band was also abrogated. Our results suggest that beta activity in the PPN is transmitted from the basal ganglia and probably comes from the STN, and the STN plays a dominant role in the network of causal interactions for beta activity. Thus, the STN may be a potential source of aberrant beta band oscillations in PD. Levodopa can inhibit beta activity in the PPN of parkinsonian rats but cannot relieve parkinsonian patients' axial symptoms clinically. Therefore, beta oscillations may not be the major cause of axial symptoms.
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Affiliation(s)
- Min Li
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Ming Zhou
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Peng Wen
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Qiang Wang
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Yong Yang
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Hu Xiao
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Zhengyuan Xie
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
| | - Xing Li
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - Ning Wang
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jinyan Wang
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
| | - Fei Luo
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jingyu Chang
- Neuroscience Research Institute of North Carolina, Winston-Salem, NC, USA
| | - Wangming Zhang
- The National Key Clinic Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China.
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Altered neuronal activity in the pedunculopontine nucleus: An electrophysiological study in a rat model of Parkinson's disease. Behav Brain Res 2016; 305:57-64. [PMID: 26924016 DOI: 10.1016/j.bbr.2016.02.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/19/2016] [Accepted: 02/23/2016] [Indexed: 01/31/2023]
Abstract
The pedunculopontine nucleus (PPN) is a new deep brain stimulation target for treating Parkinson's disease (PD). But the alterations of the PPN electrophysiological activities in PD are still debated. To investigate these potential alterations, extracellular single unit and local field potential (LFP) activities in the PPN were recorded in unilateral hemispheric 6-hydroxydopamine (6-OHDA) lesioned rats and in control rats, respectively. The spike activity results revealed two types of neurons (Type I and Type II) with distinct electrophysiological characteristics in the PPN. Both types of neurons had increased firing rate and changed firing pattern in lesioned rats when compared to control rats. Specifically, Type II neurons showed an increased firing rate when the rat state was switched from rest to locomotion. The LFP results demonstrated that lesioned rats had lower LFP power at 0.7-12Hz and higher power at 12-30Hz than did control animals in either resting or locomotor state. These findings provide a better understanding of the effects of 6-OHDA lesion on neuronal activities in the PPN and also provide a proof of the link between this structure and locomotion, which contributes to better understanding the mechanisms of the PPN functioning in the pathophysiology of PD.
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17
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Gut NK, Winn P. The pedunculopontine tegmental nucleus-A functional hypothesis from the comparative literature. Mov Disord 2016; 31:615-24. [PMID: 26880095 PMCID: PMC4949639 DOI: 10.1002/mds.26556] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 12/22/2015] [Accepted: 12/28/2015] [Indexed: 12/21/2022] Open
Abstract
We present data from animal studies showing that the pedunculopontine tegmental nucleus-conserved through evolution, compartmentalized, and with a complex pattern of inputs and outputs-has functions that involve formation and updates of action-outcome associations, attention, and rapid decision making. This is in contrast to previous hypotheses about pedunculopontine function, which has served as a basis for clinical interest in the pedunculopontine in movement disorders. Current animal literature points to it being neither a specifically motor structure nor a master switch for sleep regulation. The pedunculopontine is connected to basal ganglia circuitry but also has primary sensory input across modalities and descending connections to pontomedullary, cerebellar, and spinal motor and autonomic control systems. Functional and anatomical studies in animals suggest strongly that, in addition to the pedunculopontine being an input and output station for the basal ganglia and key regulator of thalamic (and consequently cortical) activity, an additional major function is participation in the generation of actions on the basis of a first-pass analysis of incoming sensory data. Such a function-rapid decision making-has very high adaptive value for any vertebrate. We argue that in developing clinical strategies for treating basal ganglia disorders, it is necessary to take an account of the normal functions of the pedunculopontine. We believe that it is possible to use our hypothesis to explain why pedunculopontine deep brain stimulation used clinically has had variable outcomes in the treatment of parkinsonism motor symptoms and effects on cognitive processing. © 2016 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Nadine K Gut
- Biozentrum, University of Basel, Basel, Switzerland
| | - Philip Winn
- Strathclyde Institute of Pharmacy & Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
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18
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Near-infrared light (670 nm) reduces MPTP-induced parkinsonism within a broad therapeutic time window. Exp Brain Res 2016; 234:1787-1794. [DOI: 10.1007/s00221-016-4578-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 01/28/2016] [Indexed: 10/22/2022]
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19
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Bensaid M, Michel PP, Clark SD, Hirsch EC, François C. Role of pedunculopontine cholinergic neurons in the vulnerability of nigral dopaminergic neurons in Parkinson's disease. Exp Neurol 2015; 275 Pt 1:209-19. [PMID: 26571193 DOI: 10.1016/j.expneurol.2015.11.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 10/15/2015] [Accepted: 11/10/2015] [Indexed: 10/22/2022]
Abstract
Pedunculopontine nucleus (PPN) cholinergic neurons, which exert excitatory nicotinic control over substantia nigra dopaminergic neurons, degenerate in Parkinson's disease (PD). This finding and other studies showing that nicotine, the preferential agonist of nicotinic acetylcholine receptors, is neuroprotective in experimental models of PD suggest that a deficit in PPN excitatory cholinergic inputs might contribute to the death of nigral dopaminergic neurons in PD. To explore this possibility, we used lesion paradigms of dopaminergic and/or cholinergic systems in rats and monkeys. Consistent with our hypothesis, we observed that stereotaxic lesioning of PPN cholinergic neurons with diphtheria toxin coupled to urotensin II resulted in a significant loss of nigral dopaminergic neurons in rats and induced morphological changes in these neurons in macaques. Unexpectedly, a lesion of dopaminergic neurons induced by unilateral striatal injection of 6-hydroxydopamine (6-OHDA) in rats, or by repeated systemic injections of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in macaques, led to a 29% and 7% loss of PPN cholinergic neurons, respectively. Lastly, when the PPN cholinergic lesion was performed in rats in which the dopaminergic lesion induced by 6-OHDA was in progress, loss of cholinergic neurons was more drastic than when each neurotransmitter system was lesioned separately. Thus, our results suggest that strong PPN cholinergic and dopaminergic interactions may be an important mechanism in the pathophysiology of PD.
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Affiliation(s)
- Manale Bensaid
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, UM75, U1127, UMR 7225, ICM, F-75013 Paris, France
| | - Patrick P Michel
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, UM75, U1127, UMR 7225, ICM, F-75013 Paris, France
| | - Stewart D Clark
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York 14214, United States
| | - Etienne C Hirsch
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, UM75, U1127, UMR 7225, ICM, F-75013 Paris, France
| | - Chantal François
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, UM75, U1127, UMR 7225, ICM, F-75013 Paris, France.
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20
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Li M, Zhang W. Oscillations in pedunculopontine nucleus in Parkinson's disease and its relationship with deep brain stimulation. Front Neural Circuits 2015; 9:47. [PMID: 26388741 PMCID: PMC4556974 DOI: 10.3389/fncir.2015.00047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 08/21/2015] [Indexed: 11/22/2022] Open
Abstract
The recent development of deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) for the treatment of parkinsonian patients, particularly those in advanced stages with axial symptoms, has ignited interest into the study of this brain nucleus. In contrast to the extensively studied alterations of neural activity that occur in the basal ganglia in Parkinson’s disease (PD), our understanding of the activity of the PPN remains insufficient. In recent years, however, a series of studies recording oscillatory activity in the PPN of parkinsonian patients have made important findings. Here, we briefly review recent studies that explore the different kinds of oscillations observed in the PPN of parkinsonian patients, and how they underlie the pathophysiology of PD and the efficacy of PPN-DBS in these disorders.
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Affiliation(s)
- Min Li
- The National Key Clinic Specialty, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Engineering Technology Research Center of Education Ministry of China, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University Guangzhou, China
| | - Wangming Zhang
- The National Key Clinic Specialty, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, The Engineering Technology Research Center of Education Ministry of China, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University Guangzhou, China
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21
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Deep brain stimulation of different pedunculopontine targets in a novel rodent model of parkinsonism. J Neurosci 2015; 35:4792-803. [PMID: 25810510 DOI: 10.1523/jneurosci.3646-14.2015] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The pedunculopontine tegmental nucleus (PPTg) has been proposed as a target for deep brain stimulation (DBS) in parkinsonian patients, particularly for symptoms such as gait and postural difficulties refractory to dopaminergic treatments. Several patients have had electrodes implanted aimed at the PPTg, but outcomes have been disappointing, with little evidence that gait and posture are improved. The PPTg is a heterogeneous structure. Consequently, exact target sites in PPTg, possible DBS mechanisms, and potential benefits still need systematic investigation in good animal models. We have investigated the role of PPTg in gait, developed a refined model of parkinsonism including partial loss of the PPTg with bilateral destruction of nigrostriatal dopamine neurons that mimics human pathophysiology, and investigated the effect of DBS at different PPTg locations on gait and posture using a wireless device that lets rats move freely while receiving stimulation. Neither partial nor complete lesions of PPTg caused gait deficits, underlining questions raised previously about the status of PPTg as a motor control structure. The effect of DBS in the refined and standard model of parkinsonism were very different despite minimal behavioral differences in nonstimulation control conditions. Anterior PPTg DBS caused severe episodes of freezing and worsened gait, whereas specific gait parameters were mildly improved by stimulation of posterior PPTg. These results emphasize the critical importance of intra-PPTg DBS location and highlight the need to take PPTg degeneration into consideration when modeling parkinsonian symptoms. They also further implicate a role for PPTg in the pathophysiology of parkinsonism.
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22
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Liu HG, Zhang K, Yang AC, Zhang JG. Deep brain stimulation of the subthalamic and pedunculopontine nucleus in a patient with Parkinson's disease. J Korean Neurosurg Soc 2015; 57:303-6. [PMID: 25932301 PMCID: PMC4414778 DOI: 10.3340/jkns.2015.57.4.303] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 08/17/2014] [Accepted: 08/18/2014] [Indexed: 11/27/2022] Open
Abstract
Deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is a novel therapy developed to treat Parkinson's disease. We report a patient who underwent bilateral DBS of the PPN and subthalamic nucleus (STN). He suffered from freezing of gait (FOG), bradykinesia, rigidity and mild tremors. The patient underwent bilateral DBS of the PPN and STN. We compared the benefits of PPN-DBS and STN-DBS using motor and gait subscores. The PPN-DBS provided modest improvements in the gait disorder and freezing episodes, while the STN-DBS failed to improve the dominant problems. This special case suggests that PPN-DBS may have a unique role in ameliorating the locomotor symptoms and has the potential to provide improvement in FOG.
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Affiliation(s)
- Huan-Guang Liu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Kai Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - An-Chao Yang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Jian-Guo Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China. ; Department of Stereotactic and Functional Neurosurgery, Beijing Neurosurgical Institute, Beijing, China
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23
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Morita H, Hass CJ, Moro E, Sudhyadhom A, Kumar R, Okun MS. Pedunculopontine Nucleus Stimulation: Where are We Now and What Needs to be Done to Move the Field Forward? Front Neurol 2014; 5:243. [PMID: 25538673 PMCID: PMC4255598 DOI: 10.3389/fneur.2014.00243] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 11/10/2014] [Indexed: 11/13/2022] Open
Abstract
Falls and gait impairment in Parkinson's Disease (PD) is a leading cause of morbidity and mortality, significantly impacting quality of life and contributing heavily to disability. Thus far axial symptoms, such as postural instability and gait freezing, have been refractory to current treatment approaches and remain a critical unmet need. There has been increased excitement surrounding the surgical targeting of the pedunculopontine nucleus (PPN) for addressing axial symptoms in PD. The PPN and cuneate nucleus comprise the mesencephalic locomotor region, and electrophysiologic studies in animal models and human imaging studies have revealed a key role for the PPN in gait and postural control, underscoring a potential role for DBS surgery. Previous limited studies of PPN deep brain stimulation (DBS) in treating gait symptoms have had mixed clinical outcomes, likely reflect targeting variability and the inherent challenges of targeting a small brainstem structure that is both anatomically and neurochemically heterogeneous. Diffusion tractography shows promise for more accurate targeting and standardization of results. Due to the limited experience with PPN DBS, several unresolved questions remain about targeting and programing. At present, it is unclear if there is incremental benefit with bilateral versus unilateral targeting of PPN or whether PPN targeting should be performed as an adjunct to one of the more traditional targets. The PPN also modulates non-motor functions including REM sleep, cognition, mood, attention, arousal, and these observations will require long-term monitoring to fully characterize potential side effects and benefits. Surgical targeting of the PPN is feasible and shows promise for addressing axial symptoms in PD but may require further refinements in targeting, improved imaging, and better lead design to fully realize benefits. This review summarizes the current knowledge of PPN as a DBS target and areas that need to be addressed to advance the field.
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Affiliation(s)
- Hokuto Morita
- Department of Neurology, University of Florida Center for Movement Disorders and Neurorestoration , Gainesville, FL , USA
| | - Chris J Hass
- Department of Applied Physiology and Kinesiology, University of Florida , Gainesville, FL , USA
| | - Elena Moro
- Department of Psychiatry and Neurology, CHU de Grenoble , Grenoble , France
| | - Atchar Sudhyadhom
- Department of Radiation Oncology, University of California at San Francisco , San Francisco, CA , USA
| | - Rajeev Kumar
- Rocky Mountain Movement Disorder Center , Denver, CO , USA
| | - Michael S Okun
- Department of Neurology, University of Florida Center for Movement Disorders and Neurorestoration , Gainesville, FL , USA
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24
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Martinez-Gonzalez C, van Andel J, Bolam JP, Mena-Segovia J. Divergent motor projections from the pedunculopontine nucleus are differentially regulated in Parkinsonism. Brain Struct Funct 2014; 219:1451-62. [PMID: 23708060 PMCID: PMC4072066 DOI: 10.1007/s00429-013-0579-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 05/10/2013] [Indexed: 01/28/2023]
Abstract
The pedunculopontine nucleus (PPN) is composed of neurons with different connectivity patterns that express different neurochemical markers, display distinct firing characteristics and are topographically organized in functional domains across its rostro-caudal axis. Previous reports have shown that the caudal region of the PPN is interconnected with motor regions of both the basal ganglia and brainstem/medulla. The co-distribution of ascending and descending motor outputs raises the question as to whether the PPN provides a coordinated or differential modulation of its targets in the basal ganglia and the medulla. To address this, we retrogradely labeled neurons in the two main PPN pathways involved in motor control and determined whether they project to one or both structures, their neurochemical phenotype, and their activity in normal and dopamine depleted rats, as indicated by Egr-1 expression. We show that ascending and descending motor pathways from the PPN arise largely from separate neurons that intermingle in the same region of the PPN, but have a distinct neurochemical composition and are differentially regulated in the Parkinsonian state. Thus, neurons projecting to the subthalamic nucleus consist of cholinergic, calbindin- and calretinin-expressing neurons, and Egr-1 is upregulated following a 6-hydroxydopamine lesion. In contrast, a larger proportion of neurons projecting to the gigantocellular nucleus are cholinergic, none express calbindin and the expression of Egr-1 is not changed by the dopamine lesion. Our results suggest that ascending and descending motor connections of the PPN are largely mediated by different sets of neurons and there are cell type-specific changes in Parkinsonian rats.
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Affiliation(s)
- Cristina Martinez-Gonzalez
- MRC Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3TH UK
| | - Judith van Andel
- MRC Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3TH UK
| | - J. Paul Bolam
- MRC Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3TH UK
| | - Juan Mena-Segovia
- MRC Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3TH UK
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25
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Delaville C, Cruz AV, McCoy AJ, Brazhnik E, Avila I, Novikov N, Walters JR. Oscillatory Activity in Basal Ganglia and Motor Cortex in an Awake Behaving Rodent Model of Parkinson's Disease. ACTA ACUST UNITED AC 2014; 3:221-227. [PMID: 25667820 DOI: 10.1016/j.baga.2013.12.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Exaggerated beta range (15-30 Hz) oscillatory activity is observed in the basal ganglia of Parkinson's disease (PD) patients during implantation of deep brain stimulation electrodes. This activity has been hypothesized to contribute to motor dysfunction in PD patients. However, it remains unclear how these oscillations develop and how motor circuits become entrained into a state of increased synchronization in this frequency range after loss of dopamine. It is also unclear whether this increase in neuronal synchronization actually plays a significant role in inducing the motor symptoms of this disorder. The hemiparkinsonian rat has emerged as a useful model for investigating relationships between loss of dopamine, increases in oscillatory activity in motor circuits and behavioral state. Chronic recordings from these animals show exaggerated activity in the high beta/low gamma range (30-35 Hz) in the dopamine cell-lesioned hemisphere. This activity is not evident when the animals are in an inattentive rest state, but it can be stably induced and monitored in the motor cortex and basal ganglia when they are engaged in an on-going activity such as treadmill walking. This review discusses data obtained from this animal model and the implications and limitations of this data for obtaining further insight into the significance of beta range activity in PD.
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Affiliation(s)
- Claire Delaville
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD20892-3702USA
| | - Ana V Cruz
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD20892-3702USA
| | - Alex J McCoy
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD20892-3702USA
| | - Elena Brazhnik
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD20892-3702USA
| | - Irene Avila
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD20892-3702USA
| | - Nikolay Novikov
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD20892-3702USA
| | - Judith R Walters
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke National Institutes of Health, Bethesda, MD20892-3702USA
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26
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Valencia M, Chavez M, Artieda J, Bolam JP, Mena-Segovia J. Abnormal functional connectivity between motor cortex and pedunculopontine nucleus following chronic dopamine depletion. J Neurophysiol 2013; 111:434-40. [PMID: 24174651 DOI: 10.1152/jn.00555.2013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The activity of the basal ganglia is altered in Parkinson's disease (PD) as a consequence of the degeneration of dopamine neurons in the substantia nigra pars compacta. This results in aberrant discharge patterns and expression of exaggerated oscillatory activity across the basal ganglia circuit. Altered activity has also been reported in some of the targets of the basal ganglia, including the pedunculopontine nucleus (PPN), possibly due to its close interconnectivity with most regions of the basal ganglia. However, the nature of the involvement of the PPN in the pathophysiology of PD has not been fully elucidated. Here, we recorded local field potentials in the motor cortex and the PPN in the 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD under urethane anesthesia. By means of linear and nonlinear statistics, we analyzed the synchrony between the motor cortex and the PPN and the delay in the interaction between these two structures. We observed the presence of coherent activity between the cortex and the PPN in low (5-15 Hz)- and high (25-35 Hz)-frequency bands during episodes of cortical activation. In each case, the cortex led the PPN. Dopamine depletion strengthened the interaction of the low-frequency activities by increasing the coherence specifically in the theta and alpha ranges and reduced the delay of the interaction in the gamma band. Our data show that cortical inputs play a determinant role in leading the coherent activity with the PPN and support the involvement of the PPN in the pathophysiology of PD.
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Affiliation(s)
- Miguel Valencia
- Neurophysiology Laboratory, Neuroscience Area, CIMA, Universidad de Navarra, Pamplona, Spain
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27
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Zitella LM, Mohsenian K, Pahwa M, Gloeckner C, Johnson MD. Computational modeling of pedunculopontine nucleus deep brain stimulation. J Neural Eng 2013; 10:045005. [PMID: 23723145 DOI: 10.1088/1741-2560/10/4/045005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE Deep brain stimulation (DBS) near the pedunculopontine nucleus (PPN) has been posited to improve medication-intractable gait and balance problems in patients with Parkinson's disease. However, clinical studies evaluating this DBS target have not demonstrated consistent therapeutic effects, with several studies reporting the emergence of paresthesia and oculomotor side effects. The spatial and pathway-specific extent to which brainstem regions are modulated during PPN-DBS is not well understood. APPROACH Here, we describe two computational models that estimate the direct effects of DBS in the PPN region for human and translational non-human primate (NHP) studies. The three-dimensional models were constructed from segmented histological images from each species, multi-compartment neuron models and inhomogeneous finite element models of the voltage distribution in the brainstem during DBS. MAIN RESULTS The computational models predicted that: (1) the majority of PPN neurons are activated with -3 V monopolar cathodic stimulation; (2) surgical targeting errors of as little as 1 mm in both species decrement activation selectivity; (3) specifically, monopolar stimulation in caudal, medial, or anterior PPN activates a significant proportion of the superior cerebellar peduncle (up to 60% in the human model and 90% in the NHP model at -3 V); (4) monopolar stimulation in rostral, lateral or anterior PPN activates a large percentage of medial lemniscus fibers (up to 33% in the human model and 40% in the NHP model at -3 V) and (5) the current clinical cylindrical electrode design is suboptimal for isolating the modulatory effects to PPN neurons. SIGNIFICANCE We show that a DBS lead design with radially-segmented electrodes may yield improved functional outcome for PPN-DBS.
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Affiliation(s)
- Laura M Zitella
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
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28
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State-dependent spike and local field synchronization between motor cortex and substantia nigra in hemiparkinsonian rats. J Neurosci 2012; 32:7869-80. [PMID: 22674263 DOI: 10.1523/jneurosci.0943-12.2012] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Excessive beta frequency oscillatory and synchronized activity has been reported in the basal ganglia of parkinsonian patients and animal models of the disease. To gain insight into processes underlying this activity, this study explores relationships between oscillatory activity in motor cortex and basal ganglia output in behaving rats after dopamine cell lesion. During inattentive rest, 7 d after lesion, increases in motor cortex-substantia nigra pars reticulata (SNpr) coherence emerged in the 8-25 Hz range, with significant increases in local field potential (LFP) power in SNpr but not motor cortex. In contrast, during treadmill walking, marked increases in both motor cortex and SNpr LFP power, as well as coherence, emerged in the 25-40 Hz band with a peak frequency at 30-35 Hz. Spike-triggered waveform averages showed that 77% of SNpr neurons, 77% of putative cortical interneurons, and 44% of putative pyramidal neurons were significantly phase-locked to the increased cortical LFP activity in the 25-40 Hz range. Although the mean lag between cortical and SNpr LFPs fluctuated around zero, SNpr neurons phase-locked to cortical LFP oscillations fired, on average, 17 ms after synchronized spiking in motor cortex. High coherence between LFP oscillations in cortex and SNpr supports the view that cortical activity facilitates entrainment and synchronization of activity in basal ganglia after loss of dopamine. However, the dramatic increases in cortical power and relative timing of phase-locked spiking in these areas suggest that additional processes help shape the frequency-specific tuning of the basal ganglia-thalamocortical network during ongoing motor activity.
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29
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Stein JF, Aziz TZ. Basal ganglia output to the PPN, a commentary. Exp Neurol 2011; 233:745-6. [PMID: 22134154 DOI: 10.1016/j.expneurol.2011.11.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 11/08/2011] [Accepted: 11/14/2011] [Indexed: 12/01/2022]
Affiliation(s)
- John F Stein
- Nuffield Department of Surgery, Level 3, The West Wing, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK
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30
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c-Fos expression after deep brain stimulation of the pedunculopontine tegmental nucleus in the rat 6-hydroxydopamine Parkinson model. J Chem Neuroanat 2011; 42:210-7. [DOI: 10.1016/j.jchemneu.2011.08.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 08/03/2011] [Accepted: 08/03/2011] [Indexed: 11/22/2022]
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31
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Mena-Segovia J, Bolam JP. Phasic modulation of cortical high-frequency oscillations by pedunculopontine neurons. PROGRESS IN BRAIN RESEARCH 2011; 193:85-92. [PMID: 21854957 DOI: 10.1016/b978-0-444-53839-0.00006-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Brain states are dynamically shaped by distinct neuronal systems across the brain as a result of an interplay between their intrinsic activity and the environmental demand. Subsets of brainstem and forebrain structures influence the manifestation of specific brain states (e.g., sleep or wakefulness) and contribute to their cyclic alternation. Recent evidence, however, shows that such functional partition is not observed in the brainstem, where neuronal subpopulations engage in particular patterns of activity that contribute to the emergence of phasic components during the cortical slow oscillations. Cholinergic neurons of the pedunculopontine nucleus are functionally associated with the induction of the waking state but discharge during the phase of the slow oscillations that support neuronal activity. Here, we discuss the impact of the phasic signals arising from subcortical structures on the modulation of cortical slow oscillations and their functional significance.
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Affiliation(s)
- Juan Mena-Segovia
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford, UK.
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Distinct types of non-cholinergic pedunculopontine neurons are differentially modulated during global brain states. Neuroscience 2010; 170:78-91. [PMID: 20603194 DOI: 10.1016/j.neuroscience.2010.06.068] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 06/15/2010] [Accepted: 06/25/2010] [Indexed: 11/20/2022]
Abstract
The pedunculopontine nucleus (PPN) is critically involved in brain-state transitions that promote neocortical activation. In addition, the PPN is involved in the control of several behavioral processes including locomotion, motivation and reward, but the neuronal substrates that underlie such an array of functions remain elusive. Here we analyzed the physiological properties of non-cholinergic PPN neurons in vivo across distinct brain states, and correlated these with their morphological properties after juxtacellular labeling. We show that non-cholinergic neurons in the PPN whose firing is not strongly correlated to neocortical activity are highly heterogeneous and are composed of at least three different subtypes: (1) "quiescent" neurons, which are nearly silent during slow-wave activity (SWA) but respond robustly to neocortical activation; (2) "tonic firing" neurons, which have a stationary firing rate that is independent of neocortical activity across different brain states; and (3) "irregular firing" neurons, which exhibit a variable level of correlation with neocortical activity. The majority of non-cholinergic neurons have an ascending axonal trajectory, with the exception of some irregular firing neurons that have descending axons. Furthermore, we observed asymmetric synaptic contacts within the PPN arising from the axon collaterals of labeled neurons, suggesting that excitatory, non-cholinergic neurons can shape the activity of neighboring cells. Our results provide the first evidence of distinct firing properties associated with non-cholinergic neuronal subtypes in the PPN, suggesting a functional heterogeneity, and support the notion of a local network assembled by projection neurons, the properties of which are likely to determine the output of the PPN in diverse behavioral contexts.
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Rauch F, Schwabe K, Krauss JK. Effect of deep brain stimulation in the pedunculopontine nucleus on motor function in the rat 6-hydroxydopamine Parkinson model. Behav Brain Res 2010; 210:46-53. [DOI: 10.1016/j.bbr.2010.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2009] [Revised: 01/27/2010] [Accepted: 02/01/2010] [Indexed: 10/19/2022]
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Bortolanza M, Wietzikoski EC, Boschen SL, Dombrowski PA, Latimer M, Maclaren DAA, Winn P, Da Cunha C. Functional disconnection of the substantia nigra pars compacta from the pedunculopontine nucleus impairs learning of a conditioned avoidance task. Neurobiol Learn Mem 2010; 94:229-39. [PMID: 20595069 DOI: 10.1016/j.nlm.2010.05.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/17/2010] [Accepted: 05/26/2010] [Indexed: 01/12/2023]
Abstract
The pedunculopontine tegmental nucleus (PPTg) targets nuclei in the basal ganglia, including the substantia nigra pars compacta (SNc), in which neuronal loss occurs in Parkinson's disease, a condition in which patients show cognitive as well as motor disturbances. Partial loss and functional abnormalities of neurons in the PPTg are also associated with Parkinson's disease. We hypothesized that the interaction of PPTg and SNc might be important for cognitive impairments and so investigated whether disrupting the connections between the PPTg and SNc impaired learning of a conditioned avoidance response (CAR) by male Wistar rats. The following groups were tested: PPTg unilateral; SNc unilateral; PPTg-SNc ipsilateral (ipsilateral lesions in PPTg and SNc); PPTg-SNc contralateral (contralateral lesions in PPTg and SNc); sham lesions (of each type). SNc lesions were made with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine HCl (MPTP, 0.6micromol); PPTg lesions with ibotenate (24nmol). After recovery, all rats underwent 50-trial sessions of 2-way active avoidance conditioning for 3 consecutive days. Rats with unilateral lesions in PPTg or SNc learnt this, however rats with contralateral (but not ipsilateral) combined lesions in both structures presented no sign of learning. This effect was not likely to be due to sensorimotor impairment because lesions did not affect reaction time to the tone or footshock during conditioning. However, an increased number of non-responses were observed in the rats with contralateral lesions. The results support the hypothesis that a functional interaction between PPTg and SNc is needed for CAR learning and performance.
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Affiliation(s)
- Mariza Bortolanza
- Laboratorio de Fisiologia e Farmacologia do Sistema Nervoso Central, Departamento de Farmacologia, Universidade Federal do Parana (UFPR), C.P. 19031, 81531-980 Curitiba, Brazil
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Tseng KY. Facing the lack of anti-phase oscillation in the parafascicular nucleus after dopamine depletion. Exp Neurol 2009; 219:62-5. [PMID: 19501087 DOI: 10.1016/j.expneurol.2009.05.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2009] [Revised: 05/21/2009] [Accepted: 05/22/2009] [Indexed: 10/20/2022]
Abstract
There is a large body of literature establishing that excessive neuronal synchronization and a shift in firing pattern within the cortico-basal ganglia circuit is implicated in Parkinson's disease (PD), yet a causal link between abnormal network oscillation and specific deficits in PD is lacking. It is proposed that enhanced (inhibitory) synchronous basal ganglia output could trigger anti-phase oscillatory activity in target thalamic nuclei, and entrain this abnormal synchronization within the cortico-basal ganglia loop through a reciprocal resonance mechanism. In a recent Experimental Neurology paper (2009), Parr-Brownlie et al. addressed this issue by assessing electrophysiological recordings in vivo in anesthetized control and dopamine-depleted rats induced by unilateral injection of 6-hydroxydopamine. Results from this study demonstrate that a shift in firing pattern in basal ganglia output neurons does not directly drive the distinctive oscillatory activity observed in the parafascicular nucleus after dopamine depletion. This commentary discusses possible mechanisms mediating the altered oscillatory activity found in the parafascicular nucleus after dopamine depletion and its link to the increased in-phase oscillations with synchronous firing in the subthalamic nucleus.
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Affiliation(s)
- Kuei Y Tseng
- Department of Cellular and Molecular Pharmacology, Rosalind Franklin University, The Chicago Medical School, North Chicago, IL 60064, USA.
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Parr-Brownlie LC, Poloskey SL, Bergstrom DA, Walters JR. Parafascicular thalamic nucleus activity in a rat model of Parkinson's disease. Exp Neurol 2009; 217:269-81. [PMID: 19268664 DOI: 10.1016/j.expneurol.2009.02.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2008] [Revised: 01/26/2009] [Accepted: 02/24/2009] [Indexed: 10/21/2022]
Abstract
Parkinson's disease is associated with increased oscillatory firing patterns in basal ganglia output, which are thought to disrupt thalamocortical activity. However, it is unclear how specific thalamic nuclei are affected by these changes in basal ganglia activity. The thalamic parafascicular nucleus (PFN) receives input from basal ganglia output nuclei and directly projects to the subthalamic nucleus (STN), striatum and cortex; thus basal ganglia-mediated changes on PFN activity may further impact basal ganglia and cortical functions. To investigate the impact of increased oscillatory activity in basal ganglia output on PFN activity after dopamine cell lesion, PFN single-unit and local field potential activities were recorded in neurologically intact (control) rats and in both non-lesioned and dopamine lesioned hemispheres of unilateral 6-hydroxydopamine lesioned rats anesthetized with urethane. Firing rates were unchanged 1-2 weeks after lesion; however, significantly fewer spontaneously active PFN neurons were evident. Firing pattern assessments after lesion showed that a larger proportion of PFN spike trains had 0.3-2.5 Hz oscillatory activity and significantly fewer spike trains exhibited low threshold calcium spike (LTS) bursts. In paired recordings, more PFN-STN spike oscillations were significantly correlated, but as these oscillations were in-phase, results are inconsistent with feedforward control of PFN activity by inhibitory oscillatory basal ganglia output. Furthermore, the decreased incidence of LTS bursts is incompatible with inhibitory basal ganglia output inducing rebound bursting in PFN after dopamine lesion. Together, results show that robust oscillatory activity observed in basal ganglia output nuclei after dopamine cell lesion does not directly drive changes in PFN oscillatory activity.
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Affiliation(s)
- Louise C Parr-Brownlie
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 35 Convent Drive, Building 35 Room 1C 905, Bethesda, MD 20892-3702 USA.
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Akinesia, motor oscillations and the pedunculopontine nucleus in rats and men. Exp Neurol 2008; 215:1-4. [PMID: 18977223 DOI: 10.1016/j.expneurol.2008.09.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Accepted: 09/18/2008] [Indexed: 01/10/2023]
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