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Quilgars C, Cazalets JR, Bertrand SS. Developmentally Regulated Modulation of Lumbar Motoneurons by Metabotropic Glutamate Receptors: A Cellular and Behavioral Analysis in Newborn Mice. Front Cell Neurosci 2021; 15:770250. [PMID: 34955751 PMCID: PMC8699010 DOI: 10.3389/fncel.2021.770250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 11/19/2021] [Indexed: 11/18/2022] Open
Abstract
The present study explores the impact of metabotropic glutamate receptor (mGluR) activation on activity-dependent synaptic plasticity (ADSP) and the intrinsic membrane properties of lumbar motoneurons (MNs) using a combination of biochemical, pharmacological, electrophysiological and behavioral techniques. Using spinal cord slices from C57BL/6JRJ mice at two developmental stages, 1-3 and 8-12 postnatal days (P1-P3; P8-P12, respectively), we found that ADSP expressed at glutamatergic synapses between axons conveyed in the ventrolateral funiculus (VLF) and MNs, involved mGluR activation. Using specific agonists of the three groups of mGluRs, we observed that mGluR stimulation causes subtype-specific and developmentally regulated modulation of the ADSP and synaptic transmission at VLF-MN synapses as well as the intrinsic membrane properties of MNs. RT-qPCR analysis revealed a downregulation of mGluR gene expression with age in the ventral part of the lumbar spinal cord. Interestingly, the selective harvest by laser microdissection of MNs innervating the Gastrocnemius and Tibialis anterior muscles unraveled that the level of Grm2 expression is higher in Tibialis MNs compared to Gastrocnemius MNs suggesting a specific mGluR gene expression profile in these two MN pools. Finally, we assessed the functional impact of mGluR modulation on electrically induced bouts of fictive locomotion in the isolated spinal cord preparation of P1-P3 mice, and in vivo during spontaneous episodes of swimming activity in both P1-P3 and P8-P12 mouse pups. We observed that the mGluR agonists induced distinct and specific effects on the motor burst amplitudes and period of the locomotor rhythms tested and that their actions are function of the developmental stage of the animals. Altogether our data show that the metabotropic glutamatergic system exerts a complex neuromodulation in the developing spinal lumbar motor networks and provide new insights into the expression and modulation of ADSP in MNs.
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Affiliation(s)
- Camille Quilgars
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), CNRS UMR 5287, Université de Bordeaux, Bordeaux, France.,Ecole Pratique des Hautes Etudes (EPHE), Paris Sciences et Lettres University, Paris, France
| | - Jean-René Cazalets
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), CNRS UMR 5287, Université de Bordeaux, Bordeaux, France.,Ecole Pratique des Hautes Etudes (EPHE), Paris Sciences et Lettres University, Paris, France
| | - Sandrine S Bertrand
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA), CNRS UMR 5287, Université de Bordeaux, Bordeaux, France.,Ecole Pratique des Hautes Etudes (EPHE), Paris Sciences et Lettres University, Paris, France
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Unprompted Alteration of Freely Chosen Movement Rate During Stereotyped Rhythmic Movement: Examples and Review. Motor Control 2021; 25:385-402. [PMID: 33883299 DOI: 10.1123/mc.2020-0049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 01/19/2021] [Accepted: 01/30/2021] [Indexed: 11/18/2022]
Abstract
Investigations of behavior and control of voluntary stereotyped rhythmic movement contribute to the enhancement of motor function and performance of disabled, sick, injured, healthy, and exercising humans. The present article presents examples of unprompted alteration of freely chosen movement rate during voluntary stereotyped rhythmic movements. The examples, in the form of both increases and decreases of movement rate, are taken from activities of cycling, finger tapping, and locomotion. It is described that, for example, strength training, changed power output, repeated bouts, and changed locomotion speed can elicit an unprompted alteration of freely chosen movement rate. The discussion of the examples is based on a tripartite interplay between descending drive, rhythm-generating spinal neural networks, and sensory feedback, as well as terminology from dynamic systems theory.
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Emanuelsen A, Voigt M, Madeleine P, Hansen EA. Effect of Tapping Bout Duration During Freely Chosen and Passive Finger Tapping on Rate Enhancement. J Mot Behav 2020; 53:351-363. [PMID: 32525455 DOI: 10.1080/00222895.2020.1779021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The present study investigated whether the duration of the first tapping bout, which could also be considered 'the priming', would play a role for the occurrence of the behavioral phenomenon termed repeated bout rate enhancement. Eighty-eight healthy individuals were recruited. Sixty-three of these demonstrated repeated bout rate enhancement and they were assigned to two different groups, which performed either active or passive tapping as priming. The durations of the first tapping bouts, which acted as priming, were 20, 60, 120, and 180 s. Following the first bout there was a 10 min rest and a subsequent 180 s tapping bout performed at freely chosen tapping rate. Vertical displacement and tapping force data were recorded. Rate enhancement was elicited independently of the duration of the first bout in both groups. Rate enhancement occurred without concurrent changes of the magnitude of vertical displacement, time to peak force, and duration of finger contact phase. The peak force was reduced when 180 s of tapping had been performed as priming. The increased tapping rate following priming by as little as 20 s active or passive tapping, as observed here, is suggested to be a result of increased net excitability of the nervous system.
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Affiliation(s)
- Anders Emanuelsen
- Department of Health Science and Technology, Sport Sciences - Performance and Technology, Aalborg University, Aalborg, Denmark
| | - Michael Voigt
- Department of Health Science and Technology, Sport Sciences - Performance and Technology, Aalborg University, Aalborg, Denmark
| | - Pascal Madeleine
- Department of Health Science and Technology, Sport Sciences - Performance and Technology, Aalborg University, Aalborg, Denmark
| | - Ernst Albin Hansen
- Department of Health Science and Technology, Sport Sciences - Performance and Technology, Aalborg University, Aalborg, Denmark
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Emanuelsen A, Voigt M, Madeleine P, Kjær P, Dam S, Koefoed N, Hansen EA. Repeated Bout Rate Enhancement Is Elicited by Various Forms of Finger Tapping. Front Neurosci 2018; 12:526. [PMID: 30108479 PMCID: PMC6079229 DOI: 10.3389/fnins.2018.00526] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 07/13/2018] [Indexed: 01/19/2023] Open
Abstract
Voluntary rhythmic movements, such as, for example, locomotion and other cyclic tasks, are fundamental during everyday life. Patients with impaired neural or motor function often take part in rehabilitation programs, which include rhythmic movements. Therefore, it is imperative to have the best possible understanding of control and behaviour of human voluntary rhythmic movements. A behavioural phenomenon termed repeated bout rate enhancement has been established as an increase of the freely chosen index finger tapping frequency during the second of two consecutive tapping bouts. The present study investigated whether the phenomenon would be elicited when the first bout consisted of imposed passive finger tapping or air tapping. These two forms of tapping were applied since they can be performed without descending drive (passive tapping) and without afferent feedback related to impact (air tapping) – as compared to tapping on a surface. Healthy individuals (n = 33) performed 3-min tapping bouts separated by 10 min rest. Surface electromyographic, kinetic, and kinematic data were recorded. Supportive experiments were made to measure, for example, the cortical sensory evoked potential (SEP) response during the three different forms of tapping. Results showed that tapping frequencies in the second of two consecutive bouts increased by 12.9 ± 14.8% (p < 0.001), 9.9 ± 6.0% (p = 0.001), and 16.8 ± 13.6% (p = 0.005) when the first bout had consisted of tapping, passive tapping, and air tapping, respectively. Rate enhancement occurred without increase in muscle activation. Besides, the rate enhancements occurred despite that tapping, as compared with passive tapping and air tapping, resulted in different cortical SEP responses. Based on the present findings, it can be suggested that sensory feedback in an initial bout increases the excitability of the spinal central pattern generators involved in finger tapping. This can eventually explain the phenomenon of repeated bout rate enhancement seen after a consecutive bout of finger tapping.
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Affiliation(s)
- Anders Emanuelsen
- Sport Sciences, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Michael Voigt
- Sport Sciences, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Pascal Madeleine
- Sport Sciences, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Pia Kjær
- Sport Sciences, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Sebastian Dam
- Sport Sciences, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Nikolaj Koefoed
- Sport Sciences, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Ernst A Hansen
- Sport Sciences, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
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Li WC, Zhu XY, Ritson E. Mechanosensory Stimulation Evokes Acute Concussion-Like Behavior by Activating GIRKs Coupled to Muscarinic Receptors in a Simple Vertebrate. eNeuro 2017; 4:ENEURO.0073-17.2017. [PMID: 28462392 PMCID: PMC5409982 DOI: 10.1523/eneuro.0073-17.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 04/13/2017] [Accepted: 04/14/2017] [Indexed: 11/21/2022] Open
Abstract
Most vertebrates show concussion responses when their heads are hit suddenly by heavy objects. Previous studies have focused on the direct physical injuries to the neural tissue caused by the concussive blow. We study a similar behavior in a simple vertebrate, the Xenopus laevis tadpole. We find that concussion-like behavior can be reliably induced by the mechanosensory stimulation of the head skin without direct physical impacts on the brain. Head skin stimulation activates a cholinergic pathway which then opens G protein-coupled inward-rectifying potassium channels (GIRKs) via postsynaptic M2 muscarinic receptors to inhibit brainstem neurons critical for the initiation and maintenance of swimming for up to minutes and can explain many features commonly observed immediately after concussion. We propose that some acute symptoms of concussion in vertebrates can be explained by the opening of GIRKs following mechanosensory stimulation to the head.
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Affiliation(s)
- Wen-Chang Li
- University of St Andrews, St Andrews, Fife KY16 9JP, Scotland
| | - Xiao-Yue Zhu
- University of St Andrews, St Andrews, Fife KY16 9JP, Scotland
| | - Emma Ritson
- University of St Andrews, St Andrews, Fife KY16 9JP, Scotland
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Albasanz JL, Santana S, Guzman-Sanchez F, León D, Burgos JS, Martín M. 2-Methyl-6-(phenylethynyl)pyridine Hydrochloride Modulates Metabotropic Glutamate 5 Receptors Endogenously Expressed in Zebrafish Brain. ACS Chem Neurosci 2016; 7:1690-1697. [PMID: 27635438 DOI: 10.1021/acschemneuro.6b00213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Due to phylogenetic proximity to the human, zebrafish has been recognized as a reliable model to study Alzheimer's disease (AD) and other central nervous system disorders. Furthermore, metabotropic glutamate receptors have been previously reported to be impaired in brain from AD patients. Metabotropic glutamate 5 (mGlu5) receptors are G-protein coupled receptors proposed as potential targets for therapy of different neurodegenerative disorders. Thus, MPEP (2-methyl-6-(phenylethynyl)pyridine hydrochloride), a selective noncompetitive mGlu5 receptor antagonist, has been suggested for pharmacological treatment of AD. The aim of the present work was to quantify mGlu5 receptors in brain from zebrafish and to study the possible modulation of these receptors by MPEP treatment. To this end, radioligand binding assay and open field test were used. Results showed a slightly higher presence of mGlu5 receptors in brain from male than in that from female zebrafish. However, a significant increase of mGlu5 receptor in male without variation in female was observed after MPEP treatment. This gender specific response was also observed in locomotor behavior, being significantly decreased only in male zebrafish. These results confirm the presence of mGlu5 receptors in brain from zebrafish and their gender specific modulation by selective antagonist treatment and suggest a role of these receptors on locomotor activity, which is affected in many disorders. In addition, our data point to zebrafish as a useful model to study mGlu receptor function in both healthy and pathological conditions.
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Affiliation(s)
- José Luis Albasanz
- Departamento de Química Inorgánica,
Orgánica y Bioquímica, Facultad de Medicina de Ciudad
Real/Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha, Centro Regional de Investigaciones Biomédicas (CRIB), Avenida Camilo José Cela 10, 13071 Ciudad Real, Spain
| | | | | | - David León
- Departamento de Química Inorgánica,
Orgánica y Bioquímica, Facultad de Medicina de Ciudad
Real/Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha, Centro Regional de Investigaciones Biomédicas (CRIB), Avenida Camilo José Cela 10, 13071 Ciudad Real, Spain
| | | | - Mairena Martín
- Departamento de Química Inorgánica,
Orgánica y Bioquímica, Facultad de Medicina de Ciudad
Real/Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha, Centro Regional de Investigaciones Biomédicas (CRIB), Avenida Camilo José Cela 10, 13071 Ciudad Real, Spain
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Miles GB, Sillar KT. Neuromodulation of Vertebrate Locomotor Control Networks. Physiology (Bethesda) 2011; 26:393-411. [DOI: 10.1152/physiol.00013.2011] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Vertebrate locomotion must be adaptable in light of changing environmental, organismal, and developmental demands. Much of the underlying flexibility in the output of central pattern generating (CPG) networks of the spinal cord and brain stem is endowed by neuromodulation. This review provides a synthesis of current knowledge on the way that various neuromodulators modify the properties of and connections between CPG neurons to sculpt CPG network output during locomotion.
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Affiliation(s)
- Gareth B. Miles
- School of Biology, University of St. Andrews, St. Andrews, Scotland, United Kingdom
| | - Keith T. Sillar
- School of Biology, University of St. Andrews, St. Andrews, Scotland, United Kingdom
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Iwagaki N, Miles GB. Activation of group I metabotropic glutamate receptors modulates locomotor-related motoneuron output in mice. J Neurophysiol 2011; 105:2108-20. [PMID: 21346211 DOI: 10.1152/jn.01037.2010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Fast glutamatergic transmission via ionotropic receptors is critical for the generation of locomotion by spinal motor networks. In addition, glutamate can act via metabotropic glutamate receptors (mGluRs) to modulate the timing of ongoing locomotor activity. In the present study, we investigated whether mGluRs also modulate the intensity of motor output generated by spinal motor networks. Application of the group I mGluR agonist (S)-3,5-dihydroxyphenylglycine (DHPG) reduced the amplitude and increased the frequency of locomotor-related motoneuron output recorded from the lumbar ventral roots of isolated mouse spinal cord preparations. Whole cell patch-clamp recordings of spinal motoneurons revealed multiple mechanisms by which group I mGluRs modulate motoneuron output. Although DHPG depolarized the resting membrane potential and reduced the voltage threshold for action potential generation, the activation of group I mGluRs had a net inhibitory effect on motoneuron output that appeared to reflect the modulation of fast, inactivating Na(+) currents and action potential parameters. In addition, group I mGluR activation decreased the amplitude of locomotor-related excitatory input to motoneurons. Analyses of miniature excitatory postsynaptic currents indicated that mGluRs modulate synaptic drive to motoneurons via both pre- and postsynaptic mechanisms. These data highlight group I mGluRs as a potentially important source of neuromodulation within the spinal cord that, in addition to modulating components of the central pattern generator for locomotion, can modulate the intensity of motoneuron output during motor behavior. Given that group I mGluR activation reduces motoneuron excitability, mGluRs may provide negative feedback control of motoneuron output, particularly during high levels of glutamatergic stimulation.
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Affiliation(s)
- Noboru Iwagaki
- School of Biology, University of St. Andrews, St. Andrews, Fife, United Kingdom
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Yu HJ, Yamaguchi A. 5-HT2C-like receptors in the brain of Xenopus laevis initiate sex-typical fictive vocalizations. J Neurophysiol 2009; 102:752-65. [PMID: 19474172 DOI: 10.1152/jn.90469.2008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Vocalizations of male and female African clawed frogs (Xenopus laevis) are generated by brain stem central pattern generators. Serotonin (5-HT) is likely important for vocal initiation because, when applied in vitro, sex-typical fictive vocalizations are evoked from isolated brains. To explore the mechanisms underlying vocal initiation, we identified the types of serotonin receptors mediating vocal activation pharmacologically using a whole brain, fictive preparation. The results showed that 5-HT(2C)-like receptors are important for activation of fictive vocalizations in the sexes. 5-HT(2C) receptor agonists elicited fictive vocalizations, and 5-HT(2C) receptor antagonists blocked 5-HT-induced fictive vocalizations, whereas agonists and antagonists of 5-HT(2A) and 5-HT(2B) receptors failed to initiate or block 5-HT-induced fictive vocalizations in the sexes. The results indicate that serotonin initiates fictive vocalizations by binding to 5-HT(2C)-like receptors located either within or upstream of the vocal central pattern generator in both sexes. We conclude that the basic mechanism of vocal initiation is shared by the sexes despite the differences in the actual vocalizations between males and females. Sex-typical vocalizations, therefore, most likely arise from activation of different populations of 5-HT(2C) receptor expressing cells or from differential activation of downstream pattern generating neurons.
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Affiliation(s)
- H J Yu
- Department of Biology, Boston University, Boston, Massachusetts 02215, USA.
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Nanou E, Kyriakatos A, Kettunen P, El Manira A. Separate signalling mechanisms underlie mGluR1 modulation of leak channels and NMDA receptors in the network underlying locomotion. J Physiol 2009; 587:3001-8. [PMID: 19403613 DOI: 10.1113/jphysiol.2009.172452] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Metabotropic glutamate receptor subtype 1 (mGluR1) contributes importantly to the activity of the spinal locomotor network. For example, it potentiates NMDA current and inhibits leak conductance in lamprey spinal cord neurons. In this study we examined the signalling pathways underlying the mGluR1 modulation of NMDA receptors and leak channels, respectively. Our results show that mGluR1-induced potentiation of NMDA current required activation of phospholipase C (PLC) and was independent of the increase in the intracellular Ca2+ concentration because it was unaffected by the Ca2+ chelator BAPTA and by depletion of the internal Ca2+ stores with thapsigargin. We also show that the mGluR1-mediated inhibition of leak channels is mediated by activation of G-proteins. Finally, we show that blockade of protein kinase C (PKC) abolished the mGluR1-induced inhibition of leak current without affecting the potentiation of NMDA receptors. The contribution of mGluR1-mediated modulation of leak channels to the potentiation of the locomotor cycle frequency was assessed during fictive locomotion. Blockade of PKC significantly decreased the short-term potentiation of locomotor cycle frequency by mGluR1. These results show that the effects of mGluR1 activation on the two cellular targets, the NMDA receptor and leak channels, are mediated through separate signalling pathways.
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Affiliation(s)
- Evanthia Nanou
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
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Chapman RJ, Issberner JP, Sillar KT. Group I mGluRs increase locomotor network excitability in Xenopus tadpoles via presynaptic inhibition of glycinergic neurotransmission. Eur J Neurosci 2008; 28:903-13. [PMID: 18691329 DOI: 10.1111/j.1460-9568.2008.06391.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The group I metabotropic glutamate receptor agonist (S)-3,5-dihyroxyphenylglycine (DHPG) increases the frequency of rhythmic swimming activity in Xenopus tadpoles. This study explores the possibility that group I receptor modulation occurs in part via depression of inhibitory synaptic transmission. Applications of the glycine receptor antagonist strychnine occluded the effects of DHPG, providing preliminary evidence that group I receptors affect motor network output by reducing glycinergic transmission. This evidence was supported further by intracellular and whole-cell patch-clamp recordings from presumed motorneurons. DHPG applications produced two prominent effects: (i) during swimming activity, glycinergic mid-cycle IPSPs were reduced in amplitude; and (ii) during quiescent periods, the frequency of spontaneous miniature IPSPs was also reduced. No change in membrane potential or input resistance following group I receptor activation was detected. The reduction in fast synaptic inhibition provides a plausible explanation for the increased excitability of the locomotor network, although other contributory mechanisms activated in parallel by group I receptors cannot be discounted. Aspects of this work have been published previously in abstract form [R. J. Chapman & K. T. Sillar (2003) SFN Abstracts 277.8].
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Affiliation(s)
- Rebecca J Chapman
- School of Biology, Bute Medical Buildings, University of St Andrews, St Andrews, Fife, UK.
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Friesen WO, Kristan WB. Leech locomotion: swimming, crawling, and decisions. Curr Opin Neurobiol 2008; 17:704-11. [PMID: 18339544 DOI: 10.1016/j.conb.2008.01.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Revised: 01/22/2008] [Accepted: 01/27/2008] [Indexed: 10/22/2022]
Abstract
Research on the neuronal control of locomotion in leeches spans almost four decades. Recent advances reviewed here include discoveries that: (1) interactions between multiple hormones modulate initiation of swimming; (2) stretch receptors associated with longitudinal muscles interact with the central oscillator circuit via electrical junctions; (3) intersegmental interactions, according to theoretical analyses, must be relatively weak compared to oscillator interactions within ganglia; and (4) multiple interacting neurons control the expression of alternative modes of locomotion. The innovative techniques that facilitated these advances include optical recording of membrane potential changes, simultaneous intracellular injection of high and low molecular weight fluorescent dyes, and detailed modeling via an input-output systems engineering approach.
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Affiliation(s)
- W Otto Friesen
- Department of Biology, University of Virginia, Charlottesville, VA 22903-4328, USA.
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