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Pascual-Valdunciel A, Kurukuti NM, Montero-Pardo C, Barroso FO, Pons JL. Modulation of spinal circuits following phase-dependent electrical stimulation of afferent pathways. J Neural Eng 2023; 20. [PMID: 36603216 DOI: 10.1088/1741-2552/acb087] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 01/05/2023] [Indexed: 01/06/2023]
Abstract
Objective.Peripheral electrical stimulation (PES) of afferent pathways is a tool commonly used to induce neural adaptations in some neural disorders such as pathological tremor or stroke. However, the neuromodulatory effects of stimulation interventions synchronized with physiological activity (closed-loop strategies) have been scarcely researched in the upper-limb. Here, the short-term spinal effects of a 20-minute stimulation protocol where afferent pathways were stimulated with a closed-loop strategy named selective and adaptive timely stimulation (SATS) were explored in 11 healthy subjects.Approach. SATS was applied to the radial nerve in-phase (INP) or out-of-phase (OOP) with respect to the muscle activity of the extensor carpi radialis (ECR). The neural adaptations at the spinal cord level were assessed for the flexor carpi radialis (FCR) by measuring disynaptic Group I inhibition, Ia presynaptic inhibition, Ib facilitation from the H-reflex and estimation of the neural drive before, immediately after, and 30 minutes after the intervention.Main results.SATS strategy delivered electrical stimulation synchronized with the real-time muscle activity measured, with an average delay of 17 ± 8 ms. SATS-INP induced increased disynaptic Group I inhibition (77 ± 23% of baseline conditioned FCR H-reflex), while SATS-OOP elicited the opposite effect (125 ± 46% of baseline conditioned FCR H-reflex). Some of the subjects maintained the changes after 30 minutes. No other significant changes were found for the rest of measurements.Significance.These results suggest that the short-term modulatory effects of phase-dependent PES occur at specific targeted spinal pathways for the wrist muscles in healthy individuals. Importantly, timely recruitment of afferent pathways synchronized with specific muscle activity is a fundamental principle that shall be considered when tailoring PES protocols to modulate specific neural circuits. (NCT number 04501133).
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Affiliation(s)
- Alejandro Pascual-Valdunciel
- Legs & Walking AbilityLab, Shirley Ryan AbilityLab, Chicago, IL, United States of America.,Department of PM&R, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States of America.,Neural Rehabilitation Group, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain.,E.T.S. Ingenieros de Telecomunicación, Universidad Politécnica de Madrid, Madrid, Spain
| | - Nish Mohith Kurukuti
- Legs & Walking AbilityLab, Shirley Ryan AbilityLab, Chicago, IL, United States of America.,Department of Biomedical Engineering and Mechanical Engineering, McCormick School of Engineering, Northwestern University, Chicago, IL, United States of America
| | - Cristina Montero-Pardo
- Neural Rehabilitation Group, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain.,Universidad Carlos III de Madrid, Madrid, Spain
| | - Filipe Oliveira Barroso
- Neural Rehabilitation Group, Cajal Institute, Spanish National Research Council (CSIC), Madrid, Spain
| | - José Luis Pons
- Legs & Walking AbilityLab, Shirley Ryan AbilityLab, Chicago, IL, United States of America.,Department of PM&R, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States of America.,Department of Biomedical Engineering and Mechanical Engineering, McCormick School of Engineering, Northwestern University, Chicago, IL, United States of America
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2
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van Kordelaar J, van de Ruit M, Solis-Escalante T, Aerden LAM, Meskers CGM, van Wegen EEH, Schouten AC, Kwakkel G, van der Helm FCT. The Cortical Response Evoked by Robotic Wrist Perturbations Reflects Level of Proprioceptive Impairment After Stroke. Front Hum Neurosci 2021; 15:695366. [PMID: 34858150 PMCID: PMC8631193 DOI: 10.3389/fnhum.2021.695366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 10/12/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Proprioception is important for regaining motor function in the paretic upper extremity after stroke. However, clinical assessments of proprioception are subjective and require verbal responses from the patient to applied proprioceptive stimuli. Cortical responses evoked by robotic wrist perturbations and measured by electroencephalography (EEG) may be an objective method to support current clinical assessments of proprioception. Objective: To establish whether evoked cortical responses reflect proprioceptive deficits as assessed by clinical scales and whether they predict upper extremity motor function at 26 weeks after stroke. Methods: Thirty-one patients with stroke were included. In week 1, 3, 5, 12, and 26 after stroke, the upper extremity sections of the Erasmus modified Nottingham Sensory Assessment (EmNSA-UE) and the Fugl-Meyer Motor Assessment (FM-UE) and the EEG responses (64 channels) to robotic wrist perturbations were measured. The extent to which proprioceptive input was conveyed to the affected hemisphere was estimated by the signal-to-noise ratio (SNR) of the evoked response. The relationships between SNR and EmNSA-UE as well as SNR and time after stroke were investigated using linear regression. Receiver-operating-characteristic curves were used to compare the predictive values of SNR and EmNSA-UE for predicting whether patients regained some selective motor control (FM-UE > 22) or whether they could only move their paretic upper extremity within basic limb synergies (FM-UE ≤ 22) at 26 weeks after stroke. Results: Patients (N = 7) with impaired proprioception (EmNSA-UE proprioception score < 8) had significantly smaller SNR than patients with unimpaired proprioception (N = 24) [EmNSA-UE proprioception score = 8, t(29) = 2.36, p = 0.03]. No significant effect of time after stroke on SNR was observed. Furthermore, there was no significant difference in the predictive value between EmNSA-UE and SNR for predicting motor function at 26 weeks after stroke. Conclusion: The SNR of the evoked cortical response does not significantly change as a function of time after stroke and differs between patients with clinically assessed impaired and unimpaired proprioception, suggesting that SNR reflects persistent damage to proprioceptive pathways. A similar predictive value with respect to EmNSA-UE suggests that SNR may be used as an objective predictor next to clinical sensory assessments for predicting motor function at 26 weeks after stroke.
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Affiliation(s)
- Joost van Kordelaar
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands
| | - Mark van de Ruit
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands
| | - Teodoro Solis-Escalante
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands.,Department of Rehabilitation, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Leo A M Aerden
- Department of Neurology, Reinier de Graaf Hospital, Delft, Netherlands
| | - Carel G M Meskers
- Department of Rehabilitation Medicine, Amsterdam Neuroscience and Amsterdam Movement Sciences, Amsterdam University Medical Center, Amsterdam, Netherlands
| | - Erwin E H van Wegen
- Department of Rehabilitation Medicine, Amsterdam Neuroscience and Amsterdam Movement Sciences, Amsterdam University Medical Center, Amsterdam, Netherlands
| | - Alfred C Schouten
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands.,Department of Biomedical Engineering, University of Twente, Enschede, Netherlands
| | - Gert Kwakkel
- Department of Rehabilitation Medicine, Amsterdam Neuroscience and Amsterdam Movement Sciences, Amsterdam University Medical Center, Amsterdam, Netherlands
| | - Frans C T van der Helm
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands
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3
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van der Lely S, Schmidhalter MR, Knüpfer SC, Sartori AM, Schneider MP, Stalder SA, Kessler TM, Liechti MD, Mehnert U. Lower urinary tract electrical sensory assessment: A systematic review and meta-analysis. BJU Int 2021; 130:166-180. [PMID: 34390120 PMCID: PMC9545760 DOI: 10.1111/bju.15574] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Objectives To summarize the current literature on lower urinary tract electrical sensory assessment (LUTESA), with regard to current perception thresholds (CPTs) and sensory evoked potentials (SEPs), and to discuss the applied methods in terms of technical aspects, confounding factors, and potential for lower urinary tract (LUT) diagnostics. Methods The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) statement. Medline (PubMed), Embase and Scopus were searched on 13 October 2020. Meta‐analyses were performed and methodological qualities of the included studies were defined by assessing risk of bias (RoB) as well as confounding. Results After screening 9925 articles, 80 studies (five randomized controlled trials [RCTs] and 75 non‐RCTs) were included, comprising a total of 3732 patients and 692 healthy subjects (HS). Of these studies, 61 investigated CPTs exclusively and 19 reported on SEPs, with or without corresponding CPTs. The recording of LUTCPTs and SEPs was shown to represent a safe and reliable assessment of LUT afferent nerve function in HS and patients. LUTESA demonstrated significant differences in LUT sensitivity between HS and neurological patients, as well as after interventions such as pelvic surgery or drug treatments. Pooled analyses showed that several stimulation variables (e.g. stimulation frequency, location) as well as patient characteristics might affect the main outcome measures of LUTESA (CPTs, SEP latencies, peak‐to‐peak amplitudes, responder rate). RoB and confounding was high in most studies. Conclusions Preliminary data show that CPT and SEP recordings are valuable tools to more objectively assess LUT afferent nerve function. LUTESA complements already established diagnostics such as urodynamics, allowing a more comprehensive patient evaluation. The high RoB and confounding rate was related to inconsistency and inaccuracy in reporting rather than the technique itself. LUTESA standardization and well‐designed RCTs are crucial to implement LUTESA as a clinical assessment tool.
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Affiliation(s)
- Stéphanie van der Lely
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Melanie R Schmidhalter
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Stephanie C Knüpfer
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland.,Department of Urology, University Hospital of Bonn, Bonn, Germany
| | - Andrea M Sartori
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland.,Department of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, USA
| | - Marc P Schneider
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Stephanie A Stalder
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Thomas M Kessler
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Martina D Liechti
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Ulrich Mehnert
- Department of Neuro-Urology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
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Zandvliet SB, van Wegen EEH, Campfens SF, van der Kooij H, Kwakkel G, Meskers CGM. Position-Cortical Coherence as a Marker of Afferent Pathway Integrity Early Poststroke: A Prospective Cohort Study. Neurorehabil Neural Repair 2020; 34:344-359. [PMID: 32129142 PMCID: PMC7168808 DOI: 10.1177/1545968319893289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Background. Addressing the role of somatosensory impairment, that is, afferent pathway integrity, in poststroke motor recovery may require neurophysiological assessment. Objective. We investigated the longitudinal construct validity of position-cortical coherence (PCC), that is, the agreement between mechanically evoked wrist perturbations and electroencephalography (EEG), as a measure of afferent pathway integrity. Methods. PCC was measured serially in 48 patients after a first-ever ischemic stroke in addition to Fugl-Meyer motor assessment of the upper extremity (FM-UE) and Nottingham Sensory Assessment hand-finger subscores (EmNSA-HF, within 3 and at 5, 12, and 26 weeks poststroke. Changes in PCC over time, represented by percentage presence of PCC (%PCC), mean amplitude of PCC over the affected (Amp-A) and nonaffected hemisphere (Amp-N) and a lateralization index (L-index), were analyzed, as well as their association with FM-UE and EmNSA-HF. Patients were retrospectively categorized based on FM-UE score at baseline and 26 weeks poststroke into high- and low-baseline recoverers and non-recoverers. Results. %PCC increased from baseline to 12 weeks poststroke (β = 1.6%, CI = 0.32% to 2.86%, P = .01), which was no longer significant after adjusting for EmNSA-HF and FM-UE. A significant positive association was found between %PCC, Amp-A, and EmNSA-HF. Low-baseline recoverers (n = 8) showed longitudinally significantly higher %PCC than high-baseline recoverers (n = 23). Conclusions. We demonstrated the longitudinal construct validity of %PCC and Amp-A as a measure of afferent pathway integrity. A high %PCC in low-baseline recoverers suggests that this measure also contains information on cortical excitability. Use of PCC as an EEG-based measure to address the role of somatosensory integrity to motor recovery poststroke requires further attention.
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Affiliation(s)
- Sarah B Zandvliet
- Department of Rehabilitation Medicine, Amsterdam University Medical Centers, Vrije Universiteit Amsterdam, , Amsterdam Neuroscience and Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Erwin E H van Wegen
- Department of Rehabilitation Medicine, Amsterdam University Medical Centers, Vrije Universiteit Amsterdam, , Amsterdam Neuroscience and Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - S Floor Campfens
- Department of Biomechanical Engineering, University of Twente, Enschede, The Netherlands
| | - Herman van der Kooij
- Department of Biomechanical Engineering, University of Twente, Enschede, The Netherlands
| | - Gert Kwakkel
- Department of Rehabilitation Medicine, Amsterdam University Medical Centers, Vrije Universiteit Amsterdam, , Amsterdam Neuroscience and Amsterdam Movement Sciences, Amsterdam, The Netherlands.,Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, USA.,Department of Neurorehabilitation, Amsterdam Rehabilitation Research Centres, Reade, Amsterdam, The Netherlands
| | - Carel G M Meskers
- Department of Rehabilitation Medicine, Amsterdam University Medical Centers, Vrije Universiteit Amsterdam, , Amsterdam Neuroscience and Amsterdam Movement Sciences, Amsterdam, The Netherlands.,Department of Physical Therapy and Human Movement Sciences, Northwestern University, Chicago, IL, USA
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5
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McCulloch PF, Lahrman KA, DelPrete B, DiNovo KM. Innervation of the Nose and Nasal Region of the Rat: Implications for Initiating the Mammalian Diving Response. Front Neuroanat 2018; 12:85. [PMID: 30483070 PMCID: PMC6243009 DOI: 10.3389/fnana.2018.00085] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 09/28/2018] [Indexed: 11/13/2022] Open
Abstract
Most terrestrial animals demonstrate an autonomic reflex that facilitates survival during prolonged submersion under water. This diving response is characterized by bradycardia, apnea and selective increases in peripheral vascular resistance. Stimulation of the nose and nasal passages is thought to be primarily responsible for providing the sensory afferent signals initiating this protective reflex. Consequently, the primary objective of this research was to determine the central terminal projections of nerves innervating the external nose, nasal vestibule and nasal passages of rats. We injected wheat germ agglutinin (WGA) into specific external nasal locations, into the internal nasal passages of rats both with and without intact anterior ethmoidal nerves (AENs), and directly into trigeminal nerves innervating the nose and nasal region. The central terminations of these projections within the medulla were then precisely mapped. Results indicate that the internal nasal branch of the AEN and the nasopalatine nerve, but not the infraorbital nerve (ION), provide primary innervation of the internal nasal passages. The results also suggest afferent fibers from the internal nasal passages, but not external nasal region, project to the medullary dorsal horn (MDH) in an appropriate anatomical way to cause the activation of secondary neurons within the ventral MDH that express Fos protein during diving. We conclude that innervation of the anterior nasal passages by the AEN and nasopalatine nerve is likely to provide the afferent information responsible for the activation of secondary neurons within MDH during voluntary diving in rats.
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Affiliation(s)
- Paul F McCulloch
- Department of Physiology, College Graduate Studies, Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL, United States
| | - Kenneth A Lahrman
- Department of Physiology, College Graduate Studies, Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL, United States
| | - Benjamin DelPrete
- Department of Physiology, College Graduate Studies, Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL, United States
| | - Karyn M DiNovo
- Department of Physiology, College Graduate Studies, Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL, United States
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6
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Kashyap MP, Pore SK, de Groat WC, Chermansky CJ, Yoshimura N, Tyagi P. BDNF overexpression in the bladder induces neuronal changes to mediate bladder overactivity. Am J Physiol Renal Physiol 2017; 315:F45-F56. [PMID: 29092846 DOI: 10.1152/ajprenal.00386.2017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Elevated levels of brain-derived neurotrophic factor (BDNF) in urine of overactive bladder (OAB) patients support the association of BDNF with OAB symptoms, but the causality is not known. Here, we investigated the functionality of BDNF overexpression in rat bladder following bladder wall transfection of either BDNF or luciferase (luciferase) transgenes (10 µg). One week after transfection, BDNF overexpression in bladder tissue and elevation of urine BDNF levels were observed together with increased transcript of BDNF, its cognate receptors (TrkB and p75NTR), and downstream PLCγ isoforms in bladder. BDNF overexpression can induce the bladder overactivity (BO) phenotype which is demonstrated by the increased voiding pressure and reduced intercontractile interval during transurethral open cystometry under urethane anesthesia. A role for BDNF-mediated enhancement of prejunctional cholinergic transmission in BO is supported by the significant increase in the atropine- and neostigmine-sensitive component of nerve-evoked contractions and upregulation of choline acetyltransferase, vesicular acetylcholine transporter, and transporter Oct2 and -α1 receptors. In addition, higher expression of transient receptor channels (TRPV1 and TRPA1) and pannexin-1 channels in conjunction with elevation of ATP and neurotrophins in bladder and also in L6/S1 dorsal root ganglia together support a role for sensitized afferent nerve terminals in BO. Overall, genomic changes in efferent and afferent neurons of bladder induced by the overexpression of BDNF per se establish a mechanistic link between elevated BDNF levels in urine and dysfunctional voiding observed in animal models and in OAB patients.
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Affiliation(s)
- Mahendra P Kashyap
- Department of Urology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Subrata K Pore
- Department of Urology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - William C de Groat
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | | | - Naoki Yoshimura
- Department of Urology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Pradeep Tyagi
- Department of Urology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
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7
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Dideriksen JL, Laine CM, Dosen S, Muceli S, Rocon E, Pons JL, Benito-Leon J, Farina D. Electrical Stimulation of Afferent Pathways for the Suppression of Pathological Tremor. Front Neurosci 2017; 11:178. [PMID: 28420958 PMCID: PMC5378793 DOI: 10.3389/fnins.2017.00178] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 03/20/2017] [Indexed: 11/13/2022] Open
Abstract
Pathological tremors are involuntary oscillatory movements which cannot be fully attenuated using conventional treatments. For this reason, several studies have investigated the use of neuromuscular electrical stimulation for tremor suppression. In a recent study, however, we found that electrical stimulation below the motor threshold also suppressed tremor, indicating involvement of afferent pathways. In this study, we further explored this possibility by systematically investigating how tremor suppression by afferent stimulation depends on the stimulation settings. In this way, we aimed at identifying the optimal stimulation strategy, as well as to elucidate the underlying physiological mechanisms of tremor suppression. Stimulation strategies varying the stimulation intensity and pulse timing were tested in nine tremor patients using either intramuscular or surface stimulation. Significant tremor suppression was observed in six patients (tremor suppression > 75% was observed in three patients) and the average optimal suppression level observed across all subjects was 52%. The efficiency for each stimulation setting, however, varied substantially across patients and it was not possible to identify a single set of stimulation parameters that yielded positive results in all patients. For example, tremor suppression was achieved both with stimulation delivered in an out-of-phase pattern with respect to the tremor, and with random timing of the stimulation. Overall, these results indicate that low-current stimulation of afferent fibers is a promising approach for tremor suppression, but that further research is required to identify how the effect can be maximized in the individual patient.
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Affiliation(s)
- Jakob L Dideriksen
- SMI, Department of Health Science and Technology, Aalborg UniversityAalborg, Denmark
| | - Christopher M Laine
- Brain-Body Dynamics Lab, University of Southern CaliforniaLos Angeles, CA, USA
| | - Strahinja Dosen
- Institute of Neurorehabilitation Systems, University Medical Center GöttingenGöttingen, Germany.,Clinic for Trauma Surgery, Orthopedics and Plastic Surgery, University Medical Center GöttingenGöttingen, Germany
| | - Silvia Muceli
- Institute of Neurorehabilitation Systems, University Medical Center GöttingenGöttingen, Germany.,Clinic for Trauma Surgery, Orthopedics and Plastic Surgery, University Medical Center GöttingenGöttingen, Germany
| | - Eduardo Rocon
- Center for Automation and Robotics, Consejo Superior de Investigaciones CientíficasArganda del Rey, Spain
| | - José L Pons
- Neural Rehabilitation Group, Instituto Cajal, Consejo Superior de Investigaciones CientíficasMadrid, Spain
| | | | - Dario Farina
- Department of Bioengineering, Imperial College LondonLondon, UK
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8
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Choudhary M, van Mastrigt R, van Asselt E. Effect of tibial nerve stimulation on bladder afferent nerve activity in a rat detrusor overactivity model. Int J Urol 2015; 23:253-8. [PMID: 26690557 DOI: 10.1111/iju.13033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 11/15/2015] [Indexed: 12/30/2022]
Abstract
OBJECTIVES To study the post-stimulation effect of tibial nerve stimulation on rat bladder afferent activity, and urodynamic parameters in normal and acetic acid-induced detrusor overactivity conditions. METHODS In urethane anesthetized male Wistar rats, the tibial nerve was stimulated for 30 min at 5 Hz, pulse width 200 μs and amplitude approximately threefold the threshold to induce a slight toe movement. The post-stimulation effect was studied by measuring afferent nerve activity of postganglionic pelvic nerve branches and various urodynamic parameters under two different conditions: (i) in physiological saline filling experiments (simulating normal bladder condition); and (ii) in acetic acid irritated bladders (simulating detrusor overactivity). RESULTS After 30 min of tibial nerve stimulation in saline filling experiments, the bladder capacity, threshold pressure and afferent nerve activity were not significantly different from the prestimulation measurements. The instillation of 0.5% acetic acid significantly reduced the bladder capacity and increased the afferent nerve activity. Tibial nerve stimulation significantly improved the bladder capacity and suppressed the afferent nerve activity compared with prestimulation acetic acid measurements. CONCLUSIONS Tibial nerve stimulation is able to significantly restore the bladder capacity by inhibiting afferent nerve activity in chemically irritated rat bladders. The present study provides important basic electrophysiological evidence to substantiate the clinical use of tibial nerve stimulation for treatment of symptoms related to detrusor overactivity.
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Affiliation(s)
- Mahipal Choudhary
- Department of Urology, Sector Furore, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Ron van Mastrigt
- Department of Urology, Sector Furore, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Els van Asselt
- Department of Urology, Sector Furore, Erasmus Medical Center, Rotterdam, The Netherlands
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Grinsvall C, Törnblom H, Tack J, Van Oudenhove L, Simrén M. Psychological factors selectively upregulate rectal pain perception in hypersensitive patients with irritable bowel syndrome. Neurogastroenterol Motil 2015; 27:1772-82. [PMID: 26467837 DOI: 10.1111/nmo.12689] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Accepted: 08/25/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND Visceral hypersensitivity and psychological symptoms are frequent features in irritable bowel syndrome (IBS). Exploring mechanistic pathways leading to visceral hypersensitivity is of importance to direct future studies and treatment options. In this study, we evaluated the contribution of psychological factors to the perception of painful and non-painful rectal sensations in hyper- vs normosensitive IBS patients. METHODS We included 138 IBS patients (Rome II criteria) who underwent an ascending method of limited rectal balloon distension paradigm. At the end of each distension step, subjects rated the perceived intensity of non-painful ('unpleasantness') and painful rectal sensations on visual analog scales. Sensitivity status was determined based on pain thresholds. Anxiety, depression and somatization were assessed by questionnaires. Mixed models were used to test the relationship between sensitivity status, psychological variables, and pain & unpleasantness ratings upon increasing distension. KEY RESULTS Hypersensitive IBS patients had lower sensory thresholds for pain, first perception, urge to defecate, and discomfort (p < 0.0001). Upon increasing distension, they rated both painful and non-painful sensations as more intense than normosensitive patients (p < 0.0001). Psychological factors were associated with higher pain ratings during distension in hypersensitive (p < 0.006-0.0001), but not in normosensitive patients. Anxiety, but not depression or somatization, was associated with increased intensity ratings of non-painful sensations (p < 0.001), independent of sensitivity status. CONCLUSIONS & INFERENCES Hypersensitive IBS patients are characterized by increased perception of pain, but also of non-painful sensations. Psychological factors increase the perception of painful sensations in hypersensitive patients only, whereas non-painful visceral sensations were exaggerated in anxious patients regardless of the sensitivity status.
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Affiliation(s)
- C Grinsvall
- Dept of Internal Medicine & Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,University of Gothenburg Centre for Person-Centered Care (GPCC), Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - H Törnblom
- Dept of Internal Medicine & Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,University of Gothenburg Centre for Person-Centered Care (GPCC), Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - J Tack
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - L Van Oudenhove
- Translational Research Center for Gastrointestinal Disorders (TARGID), University of Leuven, Leuven, Belgium
| | - M Simrén
- Dept of Internal Medicine & Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,University of Gothenburg Centre for Person-Centered Care (GPCC), Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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10
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Klöcker A, Gueorguiev D, Thonnard JL, Mouraux A. Peripheral vs. central determinants of vibrotactile adaptation. J Neurophysiol 2015; 115:685-91. [PMID: 26581868 DOI: 10.1152/jn.00519.2015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 11/12/2015] [Indexed: 11/22/2022] Open
Abstract
Long-lasting mechanical vibrations applied to the skin induce a reversible decrease in the perception of vibration at the stimulated skin site. This phenomenon of vibrotactile adaptation has been studied extensively, yet there is still no clear consensus on the mechanisms leading to vibrotactile adaptation. In particular, the respective contributions of 1) changes affecting mechanical skin impedance, 2) peripheral processes, and 3) central processes are largely unknown. Here we used direct electrical stimulation of nerve fibers to bypass mechanical transduction processes and thereby explore the possible contribution of central vs. peripheral processes to vibrotactile adaptation. Three experiments were conducted. In the first, adaptation was induced with mechanical vibration of the fingertip (51- or 251-Hz vibration delivered for 8 min, at 40× detection threshold). In the second, we attempted to induce adaptation with transcutaneous electrical stimulation of the median nerve (51- or 251-Hz constant-current pulses delivered for 8 min, at 1.5× detection threshold). Vibrotactile detection thresholds were measured before and after adaptation. Mechanical stimulation induced a clear increase of vibrotactile detection thresholds. In contrast, thresholds were unaffected by electrical stimulation. In the third experiment, we assessed the effect of mechanical adaptation on the detection thresholds to transcutaneous electrical nerve stimuli, measured before and after adaptation. Electrical detection thresholds were unaffected by the mechanical adaptation. Taken together, our results suggest that vibrotactile adaptation is predominantly the consequence of peripheral mechanoreceptor processes and/or changes in biomechanical properties of the skin.
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Affiliation(s)
- A Klöcker
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - D Gueorguiev
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - J L Thonnard
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - A Mouraux
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
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11
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Schiller AM, Pellegrino PR, Zucker IH. The renal nerves in chronic heart failure: efferent and afferent mechanisms. Front Physiol 2015; 6:224. [PMID: 26300788 PMCID: PMC4528173 DOI: 10.3389/fphys.2015.00224] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 07/24/2015] [Indexed: 01/09/2023] Open
Abstract
The function of the renal nerves has been an area of scientific and medical interest for many years. The recent advent of a minimally invasive catheter-based method of renal denervation has renewed excitement in understanding the afferent and efferent actions of the renal nerves in multiple diseases. While hypertension has been the focus of much this work, less attention has been given to the role of the renal nerves in the development of chronic heart failure (CHF). Recent studies from our laboratory and those of others implicate an essential role for the renal nerves in the development and progression of CHF. Using a rabbit tachycardia model of CHF and surgical unilateral renal denervation, we provide evidence for both renal efferent and afferent mechanisms in the pathogenesis of CHF. Renal denervation prevented the decrease in renal blood flow observed in CHF while also preventing increases in Angiotensin-II receptor protein in the microvasculature of the renal cortex. Renal denervation in CHF also reduced physiological markers of autonomic dysfunction including an improvement in arterial baroreflex function, heart rate variability, and decreased resting cardiac sympathetic tone. Taken together, the renal sympathetic nerves are necessary in the pathogenesis of CHF via both efferent and afferent mechanisms. Additional investigation is warranted to fully understand the role of these nerves and their role as a therapeutic target in CHF.
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Affiliation(s)
- Alicia M Schiller
- Cellular and Integrative Physiology, University of Nebraska Medical Center Omaha, NE, USA
| | - Peter R Pellegrino
- Cellular and Integrative Physiology, University of Nebraska Medical Center Omaha, NE, USA
| | - Irving H Zucker
- Cellular and Integrative Physiology, University of Nebraska Medical Center Omaha, NE, USA
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Yoshioka K, Tanahashi M, Takeda M, Masuda N. Induction of Bladder Overactivity by Nerve Growth Factor in Testes in Rats: Possible Neural Crosstalk Between the Testes and Urinary Bladder. Low Urin Tract Symptoms 2014; 8:62-7. [PMID: 26789545 DOI: 10.1111/luts.12075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/10/2014] [Accepted: 07/06/2014] [Indexed: 12/30/2022]
Abstract
OBJECTIVES To clarify the pathophysiological factor underlying neural crosstalk among pelvic organs, we investigated the possible role of nerve growth factor (NGF) in the neural crosstalk between the testes and urinary bladder. METHODS Nerve growth factor (10, 30, and 100 µg/mL) or saline was injected into the testes of male Wistar rats. The change in bladder capacity via cystometry and duration of spontaneous scratching behavior induced by NGF in conscious rats was measured. The effects of pretreatment with capsaicin on NGF-induced changes in bladder capacity and behavior were examined. Further, we evaluated the effect of analgesics, indomethacin and morphine, and pretreatment with compound 48/80 on NGF-induced scratching behavior to elucidate the mechanism of the behavior. RESULTS Injection of saline into the testes had no effect on bladder capacity or behavior. However, an injection of NGF (30 and 100 µg/mL) reduced bladder capacity, which was regarded as bladder overactivity, and evoked scratching behavior in a dose-dependent manner. Pretreatment with capsaicin inhibited NGF-induced bladder overactivity and scratching behavior. Neither indomethacin nor pretreatment with compound 48/80 affected the scratching behavior, but morphine inhibited the behavior. CONCLUSIONS The present study provides evidence of a possible new role of NGF in the testes regarding the activation of testicular primary afferent neurons mediated by capsaicin-sensitive C-fibers, which evokes bladder overactivity via neural crosstalk between the testes and the urinary bladder as well as testicular pain.
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Affiliation(s)
- Katsuro Yoshioka
- Pharmacology Research Labs, Astellas Pharma Inc., Tsukuba-shi, Japan
| | | | - Masahiro Takeda
- Pharmacology Research Labs, Astellas Pharma Inc., Tsukuba-shi, Japan
| | - Noriyuki Masuda
- Pharmacology Research Labs, Astellas Pharma Inc., Tsukuba-shi, Japan
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13
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Harwood B, Cornett KMD, Edwards DL, Brown RE, Jakobi JM. The effect of tendon vibration on motor unit activity, intermuscular coherence and force steadiness in the elbow flexors of males and females. Acta Physiol (Oxf) 2014; 211:597-608. [PMID: 24888350 DOI: 10.1111/apha.12319] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 12/31/2013] [Accepted: 05/23/2014] [Indexed: 12/01/2022]
Abstract
BACKGROUND Compartmentalized responses in motor unit (MU) activity of the short head (SH) and long head (LH) of the biceps brachii are observed following forearm position change. Differential muscle spindle afferent distribution has been proposed as a potential mechanism underlying this behaviour. Tendon vibration is an effective, non-invasive method of increasing muscle spindle afferent activity of a target muscle group offering a paradigm in which this hypothesis may be investigated further. AIM To determine the effect of tendon vibration on MU recruitment and discharge rates of the SH and LH, muscle activity of the elbow flexors and triceps brachii, intermuscular coherence among the SH, LH, brachioradialis and triceps brachii and force steadiness in young males and females during isometric elbow flexion. METHODS Intramuscular electromyography (EMG) of the SH and LH, and surface EMG of the elbow flexors were recorded pre- and post-vibration during low-force isometric contractions. Motor unit recruitment thresholds, MU discharge rates and MU discharge variability; surface EMG amplitude, intermuscular coherence and force steadiness were determined pre- and post-vibration. RESULTS Differential changes in all MU properties, EMG amplitude and intermuscular coherence were observed among elbow flexors. Although MU properties exhibited differential changes, they accounted for little variance in isometric force steadiness. However, intermuscular EMG coherence among all muscles investigated was reduced post-vibration. CONCLUSION Uncoupling of common oscillatory input as a result of differential muscle spindle afferent inputs to elbow flexors may be responsible for the reduction in force steadiness following tendon vibration and a forearm position change.
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Affiliation(s)
- B. Harwood
- Health and Exercise Science; University of British Columbia Okanagan; Kelowna BC Canada
- Department of Physiology; University of Arizona; Tucson AZ USA
| | - K. M. D. Cornett
- Health and Exercise Science; University of British Columbia Okanagan; Kelowna BC Canada
| | - D. L. Edwards
- Human Kinetics; University of Windsor; Windsor ON Canada
| | - R. E. Brown
- Health and Exercise Science; University of British Columbia Okanagan; Kelowna BC Canada
| | - J. M. Jakobi
- Department of Physiology; University of Arizona; Tucson AZ USA
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Bruns TM, Weber DJ, Gaunt RA. Microstimulation of afferents in the sacral dorsal root ganglia can evoke reflex bladder activity. Neurourol Urodyn 2014; 34:65-71. [PMID: 24464833 DOI: 10.1002/nau.22514] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 09/19/2013] [Indexed: 11/07/2022]
Abstract
AIMS Pudendal afferent fibers can be excited using electrical stimulation to evoke reflex bladder activity. While this approach shows promise for restoring bladder function, stimulation of desired pathways, and integration of afferent signals for sensory feedback remains challenging. At sacral dorsal root ganglia (DRG), the convergence of pelvic and pudendal afferent fibers provides a unique location for access to lower urinary tract neurons. Our goal in this study was to demonstrate the potential of microstimulation in sacral DRG for evoking reflex bladder responses. METHODS Penetrating microelectrode arrays were inserted in the left S1 and S2 DRG of six anesthetized adult male cats. While the bladder volume was held at a level below the leak volume, single and multiple channel stimulation was performed using various stimulation patterns. RESULTS Reflex bladder excitation was observed in five cats, for stimulation in either S1 or S2 DRG at 1 Hz and 30-33 Hz with a pulse amplitude of 10-50 µA. Bladder relaxation was observed during a few trials. Adjacent electrodes frequently elicited very different responses. CONCLUSIONS These results demonstrate the potential of low-current microstimulation to recruit reflexive bladder responses. An approach such as this could be integrated with DRG recordings of bladder afferents to provide a closed-loop bladder neuroprosthesis.
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Affiliation(s)
- Tim M Bruns
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, Pennysylvania
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Takahashi R, Yoshizawa T, Yunoki T, Tyagi P, Naito S, de Groat WC, Yoshimura N. Hyperexcitability of bladder afferent neurons associated with reduction of Kv1.4 α-subunit in rats with spinal cord injury. J Urol 2013; 190:2296-304. [PMID: 23896350 DOI: 10.1016/j.juro.2013.07.058] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/19/2013] [Indexed: 12/22/2022]
Abstract
PURPOSE To clarify the functional and molecular mechanisms inducing hyperexcitability of C-fiber bladder afferent pathways after spinal cord injury we examined changes in the electrophysiological properties of bladder afferent neurons, focusing especially on voltage-gated K channels. MATERIALS AND METHODS Freshly dissociated L6-S1 dorsal root ganglion neurons were prepared from female spinal intact and spinal transected (T9-T10 transection) Sprague Dawley® rats. Whole cell patch clamp recordings were performed on individual bladder afferent neurons. Kv1.2 and Kv1.4 α-subunit expression levels were also evaluated by immunohistochemical and real-time polymerase chain reaction methods. RESULTS Capsaicin sensitive bladder afferent neurons from spinal transected rats showed increased cell excitability, as evidenced by lower spike activation thresholds and a tonic firing pattern. The peak density of transient A-type K+ currents in capsaicin sensitive bladder afferent neurons from spinal transected rats was significantly less than that from spinal intact rats. Also, the KA current inactivation curve was displaced to more hyperpolarized levels after spinal transection. The protein and mRNA expression of Kv1.4 α-subunits, which can form transient A-type K+ channels, was decreased in bladder afferent neurons after spinal transection. CONCLUSIONS Results indicate that the excitability of capsaicin sensitive C-fiber bladder afferent neurons is increased in association with reductions in transient A-type K+ current density and Kv1.4 α-subunit expression in injured rats. Thus, the Kv1.4 α-subunit could be a molecular target for treating overactive bladder due to neurogenic detrusor overactivity.
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Affiliation(s)
- Ryosuke Takahashi
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania; Department of Urology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Abstract
Research over the past 15 years has helped to clarify the anatomy and physiology of itch, the clinical features of neuropathic itch syndromes and the scientific underpinning of effective treatments. Two itch-sensitive pathways exist: a histamine-stimulated pathway that uses mechanically insensitive C-fibres, and a cowhage-stimulated pathway primarily involving polymodal C-fibres. Interactions with pain continue to be central to explaining various aspects of itch. Certain spinal interneurons (Bhlhb5) inhibit itch pathways within the dorsal horn; they may represent mediators between noxious and pruritic pathways, and allow scratch to inhibit itch. In the brain, functional imaging studies reveal diffuse activation maps for itch that overlap, but not identically, with pain maps. Neuropathic itch syndromes are chronic itch states due to dysfunction of peripheral or central nervous system structures. The most recognized are postherpetic itch, brachioradial pruritus, trigeminal trophic syndrome, and ischaemic stroke-related itch. These disorders affect a patient's quality of life to a similar extent as neuropathic pain. Treatment of neuropathic itch focuses on behavioural interventions (e.g., skin protection) followed by stepwise trials of topical agents (e.g., capsaicin), antiepileptic drugs (e.g., gabapentin), injection of other agents (e.g., botulinum A toxin), and neurostimulation techniques (e.g., cutaneous field stimulation). The involved mechanisms of action include desensitization of nerve fibres (in the case of capsaicin) and postsynaptic blockade of calcium channels (for gabapentin). In the future, particular histamine receptors, protease pathway molecules, and vanilloids may serve as targets for novel antipruritic agents.
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Affiliation(s)
- Amar Dhand
- Department of Neurology, University of California, San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0114, USA
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Slomianka L, Amrein I, Knuesel I, Sørensen JC, Wolfer DP. Hippocampal pyramidal cells: the reemergence of cortical lamination. Brain Struct Funct 2011; 216:301-17. [PMID: 21597968 PMCID: PMC3197924 DOI: 10.1007/s00429-011-0322-0] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 04/26/2011] [Indexed: 12/16/2022]
Abstract
The increasing resolution of tract-tracing studies has led to the definition of segments along the transverse axis of the hippocampal pyramidal cell layer, which may represent functionally defined elements. This review will summarize evidence for a morphological and functional differentiation of pyramidal cells along the radial (deep to superficial) axis of the cell layer. In many species, deep and superficial sublayers can be identified histologically throughout large parts of the septotemporal extent of the hippocampus. Neurons in these sublayers are generated during different periods of development. During development, deep and superficial cells express genes (Sox5, SatB2) that also specify the phenotypes of superficial and deep cells in the neocortex. Deep and superficial cells differ neurochemically (e.g. calbindin and zinc) and in their adult gene expression patterns. These markers also distinguish sublayers in the septal hippocampus, where they are not readily apparent histologically in rat or mouse. Deep and superficial pyramidal cells differ in septal, striatal, and neocortical efferent connections. Distributions of deep and superficial pyramidal cell dendrites and studies in reeler or sparsely GFP-expressing mice indicate that this also applies to afferent pathways. Histological, neurochemical, and connective differences between deep and superficial neurons may correlate with (patho-) physiological phenomena specific to pyramidal cells at different radial locations. We feel that an appreciation of radial subdivisions in the pyramidal cell layer reminiscent of lamination in other cortical areas may be critical in the interpretation of studies of hippocampal anatomy and function.
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Affiliation(s)
- Lutz Slomianka
- Institute of Anatomy, University of Zürich, 8057 Zürich, Switzerland.
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