These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Functional Recovery of Denervated Skeletal Muscle with Sensory or Mixed Nerve Protection: A Pilot Study  

PubMed Central

Functional recovery is usually poor following peripheral nerve injury when reinnervation is delayed. Early innervation by sensory nerve has been indicated to prevent atrophy of the denervated muscle. It is hypothesized that early protection with sensory axons is adequate to improve functional recovery of skeletal muscle following prolonged denervation of mixed nerve injury. In this study, four groups of rats received surgical denervation of the tibial nerve. The proximal and distal stumps of the tibial nerve were ligated in all animals except for those in the immediate repair group. The experimental groups underwent denervation with nerve protection of peroneal nerve (mixed protection) or sural nerve (sensory protection). The experimental and unprotected groups had a stage II surgery in which the trimmed proximal and distal tibial nerve stumps were sutured together. After 3 months of recovery, electrophysiological, histological and morphometric parameters were assessed. It was detected that the significant muscle atrophy and a good preserved structure of the muscle were observed in the unprotected and protective experimental groups, respectively. Significantly fewer numbers of regenerated myelinated axons were observed in the sensory-protected group. Enhanced recovery in the mixed protection group was indicated by the results of the muscle contraction force tests, regenerated myelinated fiber, and the results of the histological analysis. Our results suggest that early axons protection by mixed nerve may complement sensory axons which are required for promoting functional recovery of the denervated muscle natively innervated by mixed nerve. PMID:24244555

Li, Qing Tian; Zhang, Pei Xun; Yin, Xiao Feng; Han, Na; Kou, Yu Hui; Deng, Jiu Xu; Jiang, Bao Guo

2013-01-01

2

Peripheral Nerve Damage Facilitates Functional Innervation of Brain Grafts in Adult Sensory Cortex  

NASA Astrophysics Data System (ADS)

The neuralb pathways that relay information from cutaneous receptors to the cortex provide the somatic sensory information needed for cortical function. The last sensory relay neurons in this pathway have cell bodies in the thalamus and axons that synapse on neurons in the somatosensory cortex. After cortical lesions that damage mature thalamocortical fibers in the somatosensory cortex, we have attempted to reestablish somatosensory cortical function by grafting embryonic neocortical cells into the lesioned area. Such grafts survive in adult host animals but are not innervated by thalamic neurons, and consequently the grafted neurons show little if any spontaneous activity and no responses to cutaneous stimuli. We have reported that transection of peripheral sensory nerves prior to grafting ``conditions'' or ``primes'' the thalamic neurons in the ventrobasal complex so that they extend axons into grafts subsequently placed in the cortical domain of the cut nerve. In this report we present evidence that the ingrowth of ventrobasal fibers leads to graft neurons that become functionally integrated into the sensory circuitry of the host brain. Specifically, the conditioning lesions made prior to grafting produce graft neurons that are spontaneously active and can be driven by natural activation of cutaneous receptors or electrical stimulation of the transected nerve after it regenerates. Furthermore, oxidative metabolism in these grafts reaches levels that are comparable to normal cortex, whereas without prior nerve cut, oxidative metabolism is abnormally low in neocortical grafts. We conclude that damage to the sensory periphery transsynaptically stimulates reorganization of sensory pathways through mechanisms that include axonal elongation and functional synaptogenesis.

Ebner, Ford F.; Erzurumlu, Reha S.; Lee, Stefan M.

1989-01-01

3

Peripheral nerve damage facilitates functional innervation of brain grafts in adult sensory cortex.  

PubMed Central

The neural pathways that relay information from cutaneous receptors to the cortex provide the somatic sensory information needed for cortical function. The last sensory relay neurons in this pathway have cell bodies in the thalamus and axons that synapse on neurons in the somatosensory cortex. After cortical lesions that damage mature thalamocortical fibers in the somatosensory cortex, we have attempted to reestablish somatosensory cortical function by grafting embryonic neocortical cells into the lesioned area. Such grafts survive in adult host animals but are not innervated by thalamic neurons, and consequently the grafted neurons show little if any spontaneous activity and no responses to cutaneous stimuli. We have reported that transection of peripheral sensory nerves prior to grafting "conditions" or "primes" the thalamic neurons in the ventrobasal complex so that they extend axons into grafts subsequently placed in the cortical domain of the cut nerve. In this report we present evidence that the ingrowth of ventrobasal fibers leads to graft neurons that become functionally integrated into the sensory circuitry of the host brain. Specifically, the conditioning lesions made prior to grafting produce graft neurons that are spontaneously active and can be driven by natural activation of cutaneous receptors or electrical stimulation of the transected nerve after it regenerates. Furthermore, oxidative metabolism in these grafts reaches levels that are comparable to normal cortex, whereas without prior nerve cut, oxidative metabolism is abnormally low in neocortical grafts. We conclude that damage to the sensory periphery transsynaptically stimulates reorganization of sensory pathways through mechanisms that include axonal elongation and functional synaptogenesis. Images PMID:2911603

Ebner, F F; Erzurumlu, R S; Lee, S M

1989-01-01

4

The Relationship of Vitamin B12 and Sensory and Motor Peripheral Nerve Function in Older Adults  

PubMed Central

Objectives To examine whether deficient B12 status or low serum B12 levels are associated with worse sensory and motor peripheral nerve function in older adults. Design Cross-sectional. Setting Health, Aging and Body Composition Study. Participants Two thousand two hundred eighty-seven adults aged 72–83 years [mean age: 76.5 ± 2.9 years; 51.4% female; 38.3% black]. Measurements Low serum B12 was defined based solely on serum B12 of <260 pmol/L, whereas deficient B12 status was defined as B12 <260 pmol/L, methylmalonic acid [MMA] >271 nmol/L and MMA >2-methylcitrate. Peripheral nerve function was assessed by peroneal nerve conduction amplitude and velocity [NCV] (motor); 1.4g/10g monofilament detection; average vibration threshold detection; and peripheral neuropathy symptoms [numbness; aching/burning pain] (sensory). Results B12 deficient status was found in 7.0% and an additional 10.1% had low serum B12 levels. B12 deficient status was associated with greater insensitivity to light (1.4g) touch (OR: 1.50; 95% CI: [1.06, 2.13]) and worse NCV [42.3 m/s vs. 43.5 m/s] (? =?1.16; p=0.01), after multivariable adjustment for demographics, lifestyle factors, and health conditions. Associations were consistent for the alternative definition using low serum B12 only. No significant associations were found for deficient B12 status or the alternative low serum B12 definition and vibration detection, nerve conduction amplitude, or peripheral neuropathy symptoms. Conclusion Poor B12 (deficient B12 status and low serum B12) is associated with worse sensory and motor peripheral nerve function. Nerve function impairments may lead to physical function declines and disability in older adults, suggesting that prevention and treatment of low B12 levels may be important to evaluate. PMID:22690982

Leishear, Kira; Boudreau, Robert M.; Studenski, Stephanie A.; Ferrucci, Luigi; Rosano, Caterina; de Rekeneire, Nathalie; Houston, Denise K.; Kritchevsky, Stephen B.; Schwartz, Ann V.; Vinik, Aaron I.; Hogervorst, Eva; Yaffe, Kristine; Harris, Tamara B.; Newman, Anne B.; Strotmeyer, Elsa S.

2012-01-01

5

The relationship of nerve fibre pathology to sensory function in entrapment neuropathy  

PubMed Central

Surprisingly little is known about the impact of entrapment neuropathy on target innervation and the relationship of nerve fibre pathology to sensory symptoms and signs. Carpal tunnel syndrome is the most common entrapment neuropathy; the aim of this study was to investigate its effect on the morphology of small unmyelinated as well as myelinated sensory axons and relate such changes to somatosensory function and clinical symptoms. Thirty patients with a clinical and electrophysiological diagnosis of carpal tunnel syndrome [17 females, mean age (standard deviation) 56.4 (15.3)] and 26 age and gender matched healthy volunteers [18 females, mean age (standard deviation) 51.0 (17.3)] participated in the study. Small and large fibre function was examined with quantitative sensory testing in the median nerve territory of the hand. Vibration and mechanical detection thresholds were significantly elevated in patients with carpal tunnel syndrome (P < 0.007) confirming large fibre dysfunction and patients also presented with increased thermal detection thresholds (P < 0.0001) indicative of C and A?-fibre dysfunction. Mechanical and thermal pain thresholds were comparable between groups (P > 0.13). A skin biopsy was taken from a median nerve innervated area of the proximal phalanx of the index finger. Immunohistochemical staining for protein gene product 9.5 and myelin basic protein was used to evaluate morphological features of unmyelinated and myelinated axons. Evaluation of intraepidermal nerve fibre density showed a striking loss in patients (P < 0.0001) confirming a significant compromise of small fibres. The extent of Meissner corpuscles and dermal nerve bundles were comparable between groups (P > 0.07). However, patients displayed a significant increase in the percentage of elongated nodes (P < 0.0001), with altered architecture of voltage-gated sodium channel distribution. Whereas neither neurophysiology nor quantitative sensory testing correlated with patients’ symptoms or function deficits, the presence of elongated nodes was inversely correlated with a number of functional and symptom related scores (P < 0.023). Our findings suggest that carpal tunnel syndrome does not exclusively affect large fibres but is associated with loss of function in modalities mediated by both unmyelinated and myelinated sensory axons. We also document for the first time that entrapment neuropathies lead to a clear reduction in intraepidermal nerve fibre density, which was independent of electrodiagnostic test severity. The presence of elongated nodes in the target tissue further suggests that entrapment neuropathies affect nodal structure/myelin well beyond the focal compression site. Interestingly, nodal lengthening may be an adaptive phenomenon as it inversely correlates with symptom severity. PMID:25348629

Schmid, Annina B.; Bland, Jeremy D. P.; Bhat, Manzoor A.

2014-01-01

6

The relationship of nerve fibre pathology to sensory function in entrapment neuropathy.  

PubMed

Surprisingly little is known about the impact of entrapment neuropathy on target innervation and the relationship of nerve fibre pathology to sensory symptoms and signs. Carpal tunnel syndrome is the most common entrapment neuropathy; the aim of this study was to investigate its effect on the morphology of small unmyelinated as well as myelinated sensory axons and relate such changes to somatosensory function and clinical symptoms. Thirty patients with a clinical and electrophysiological diagnosis of carpal tunnel syndrome [17 females, mean age (standard deviation) 56.4 (15.3)] and 26 age and gender matched healthy volunteers [18 females, mean age (standard deviation) 51.0 (17.3)] participated in the study. Small and large fibre function was examined with quantitative sensory testing in the median nerve territory of the hand. Vibration and mechanical detection thresholds were significantly elevated in patients with carpal tunnel syndrome (P<0.007) confirming large fibre dysfunction and patients also presented with increased thermal detection thresholds (P<0.0001) indicative of C and A?-fibre dysfunction. Mechanical and thermal pain thresholds were comparable between groups (P>0.13). A skin biopsy was taken from a median nerve innervated area of the proximal phalanx of the index finger. Immunohistochemical staining for protein gene product 9.5 and myelin basic protein was used to evaluate morphological features of unmyelinated and myelinated axons. Evaluation of intraepidermal nerve fibre density showed a striking loss in patients (P<0.0001) confirming a significant compromise of small fibres. The extent of Meissner corpuscles and dermal nerve bundles were comparable between groups (P>0.07). However, patients displayed a significant increase in the percentage of elongated nodes (P<0.0001), with altered architecture of voltage-gated sodium channel distribution. Whereas neither neurophysiology nor quantitative sensory testing correlated with patients' symptoms or function deficits, the presence of elongated nodes was inversely correlated with a number of functional and symptom related scores (P<0.023). Our findings suggest that carpal tunnel syndrome does not exclusively affect large fibres but is associated with loss of function in modalities mediated by both unmyelinated and myelinated sensory axons. We also document for the first time that entrapment neuropathies lead to a clear reduction in intraepidermal nerve fibre density, which was independent of electrodiagnostic test severity. The presence of elongated nodes in the target tissue further suggests that entrapment neuropathies affect nodal structure/myelin well beyond the focal compression site. Interestingly, nodal lengthening may be an adaptive phenomenon as it inversely correlates with symptom severity. PMID:25348629

Schmid, Annina B; Bland, Jeremy D P; Bhat, Manzoor A; Bennett, David L H

2014-12-01

7

Bladder reinnervation using a primarily motor donor nerve (femoral nerve branches) is functionally superior to using a primarily sensory donor nerve (genitofemoral nerve)  

PubMed Central

Purpose To determine whether transfer of a primarily motor nerve (Femoral, F) to the anterior vesicle branch of the pelvic nerve (PN) allows more effective bladder reinnervation than a primarily sensory nerve (genitofemoral, GF). Methods Forty-one female mongrel hounds underwent bladder decentralization, decentralization and then bilateral nerve transfer (GFNT and FNT) or were sham/unoperated controls. Decentralization was achieved by bilateral transection of all sacral roots that induce bladder contractions upon electrical stimulation. The retrograde neuronal labeling dye fluorogold was injected into the bladder 3 weeks prior to euthanasia. Results Increased detrusor pressure after direct stimulation of the transferred nerve, lumbar spinal cord or spinal roots was observed in 12/17 GFNT dogs (mean detrusor pressure = 7.6±1.4 cmH2O) and in 9/10 FNT-V dogs (mean detrusor pressure = 11.7±3.1 cm H2O). The mean detrusor pressures after direct electrical stimulation of transferred femoral nerves were statistically significantly greater than after stimulation of the transferred genitofemoral nerves. Retrogradely labeled neurons from the bladder observed in upper lumbar cord segments after GFNT and FNT confirmed bladder reinnervation as did labeled axons at the nerve transfer site. Conclusions While transfer of either a mixed sensory and motor nerve (GFN) or a primarily motor nerve (FN) can reinnervate the bladder, using a primarily motor nerve provides greater return of nerve-evoked detrusor contraction. This surgical approach may be useful for patients with lower motor spinal cord injury to accomplish bladder emptying. PMID:25066874

Gomez-Amaya, Sandra M.; Barbe, Mary F.; Brown, Justin M.; Lamarre, Neil S.; Braverman, Alan S.; Massicotte, Vicky S.; Ruggieri, Michael R.

2014-01-01

8

Median Nerve Mistaken for Palmaris Longus Tendon: Restoration of Function with Sensory Nerve Transfers  

Microsoft Academic Search

Intraoperative iatrogenic nerve injuries occur despite vigilance in the operating room. Most of these injuries occur as a\\u000a result of patient positioning, traction or pressure injury, hematoma, or technical error. The median nerve is especially susceptible\\u000a to injury during carpal tunnel release. A rare but devastating injury of the median nerve is complete transection. The number\\u000a of devastating injuries is

Renata V. Weber; Susan E. Mackinnon

2007-01-01

9

The functions of TRPA1 and TRPV1: moving away from sensory nerves  

PubMed Central

The transient receptor potential vanilloid 1 and ankyrin 1 (TRPV1 and TRPA1, respectively) channels are members of the TRP superfamily of structurally related, non-selective cation channels. It is rapidly becoming clear that the functions of TRPV1 and TRPA1 interlink with each other to a considerable extent. This is especially clear in relation to pain and neurogenic inflammation where TRPV1 is coexpressed on the vast majority of TRPA1-expressing sensory nerves and both integrate a variety of noxious stimuli. The more recent discovery that both TRPV1 and TRPA1 are expressed on a multitude of non-neuronal sites has led to a plethora of research into possible functions of these receptors. Non-neuronal cells on which TRPV1 and TRPA1 are expressed vary from vascular smooth muscle to keratinocytes and endothelium. This review will discuss the expression, functionality and roles of these non-neuronal TRP channels away from sensory nerves to demonstrate the diverse nature of TRPV1 and TRPA1 in addition to a direct role in pain and neurogenic inflammation. PMID:22233379

Fernandes, ES; Fernandes, MA; Keeble, JE

2012-01-01

10

Effect of spinal cord stimulation on sensory nerve conduction threshold functional measures.  

PubMed

Background. Spinal cord stimulation (SCS) is being used with increasing frequency in the treatment of various chronic pain conditions. There is a paucity of reliable outcome data regarding changes in pain tolerance and peripheral sensory nerve function. The automated electrodiagnostic neuroselective sensory Nerve Conduction Threshold (sNCT) test measures painless current perception thresholds (CPTs) and atraumatic pain tolerance thresholds (PTTs). The ability of the sNCT test to independently evaluate small and large fiber function may have particular relevance for evaluating response to SCS. Methods/Results. Sixteen patients with implanted SCS systems and lower extremity neuropathic pain of greater than 6-months duration were tested using a standardized protocol, pre- and post-SCS. CPT and PTT measures (Neurometer, CPT/C Neurotron, Inc. Baltimore, MD) were obtained from the distal phalange of the most symptomatic extremity and at an ipsilateral asymptomatic control site. Only CPTs at the symptomatic site (2000 Hz only) and at the control site (5 Hz only) reached statistical significance. Changes in CPTs at other frequencies, and changes in PTTs at all frequencies (symptomatic and control sites) were not statistically significant. Conclusion. The results of this study appear to substantiate the postulates that both segmental and suprasegmental effects are involved in SCS-mediated analgesia. SCS modulates segmental large afferent fiber input as reflected by a statistically significant increase in large fiber CPTs (2000 Hz) at the symptomatic site post-SCS. A statistically significant increase in small fiber (5 Hz) CPTs at the control site suggests a central sensory (suprasegmental) modulating effect on nociceptive fiber activity. sNCT testing provided reliable outcome data for evaluating response to SCS. PMID:22151462

Aló, K M; Chado, H N

2000-08-01

11

TRPM8 function and expression in vagal sensory neurons and afferent nerves innervating guinea pig esophagus.  

PubMed

Sensory transduction in esophageal afferents requires specific ion channels and receptors. TRPM8 is a new member of the transient receptor potential (TRP) channel family and participates in cold- and menthol-induced sensory transduction, but its role in visceral sensory transduction is still less clear. This study aims to determine TRPM8 function and expression in esophageal vagal afferent subtypes. TRPM8 agonist WS-12-induced responses were first determined in nodose and jugular neurons by calcium imaging and then investigated by whole cell patch-clamp recordings in Dil-labeled esophageal nodose and jugular neurons. Extracellular single-unit recordings were performed in nodose and jugular C fiber neurons using ex vivo esophageal-vagal preparations with intact nerve endings in the esophagus. TRPM8 mRNA expression was determined by single neuron RT-PCR in Dil-labeled esophageal nodose and jugular neurons. The TRPM8 agonist WS-12 elicited calcium influx in a subpopulation of jugular but not nodose neurons. WS-12 activated outwardly rectifying currents in esophageal Dil-labeled jugular but not nodose neurons in a dose-dependent manner, which could be inhibited by the TRPM8 inhibitor AMTB. WS-12 selectively evoked action potential discharges in esophageal jugular but not nodose C fibers. Consistently, TRPM8 transcripts were highly expressed in esophageal Dil-labeled TRPV1-positive jugular neurons. In summary, the present study demonstrated a preferential expression and function of TRPM8 in esophageal vagal jugular but not nodose neurons and C fiber subtypes. This provides a distinctive role of TRPM8 in esophageal sensory transduction and may lead to a better understanding of the mechanisms of esophageal sensation and nociception. PMID:25591866

Yu, Xiaoyun; Hu, Youtian; Ru, Fei; Kollarik, Marian; Undem, Bradley J; Yu, Shaoyong

2015-03-15

12

Roles of sensory nerves in the regulation of radiation-induced structural and functional changes in the heart  

PubMed Central

Purpose Radiation-induced heart disease (RIHD) is a chronic severe side effect of radiotherapy of intrathoracic and chest wall tumors. The heart contains a dense network of sensory neurons that are not only involved in monitoring of cardiac events such as ischemia/reperfusion, but also play a role in cardiac tissue homeostasis, preconditioning, and repair. The purpose of this study was to examine the role of sensory nerves in RIHD. Methods and Materials Male Sprague-Dawley rats were administered capsaicin to permanently ablate sensory nerves, two weeks before local image-guided heart X-ray irradiation with a single dose of 21 Gy. During the 6-months follow up time, heart function was assessed with high resolution echocardiography. At 6 months after irradiation, cardiac structural and molecular changes were examined with histology, immunohistochemistry, and Western-Blots. Results Capsaicin-pretreatment blunted the effects of radiation on myocardial fibrosis and mast cell infiltration and activity. On the other hand, capsaicin-pretreatment caused a small but significant reduction in cardiac output at 6 months after irradiation. Capsaicin did not alter the effects of radiation on cardiac macrophage number or indicators of autophagy and apoptosis. Conclusions These results suggest that sensory nerves, while playing a predominantly protective role in radiation-induced cardiac function changes, may eventually enhance radiation-induced myocardial fibrosis and mast cell activity. PMID:24331664

Sridharan, Vijayalakshmi; Tripathi, Preeti; Sharma, Sunil; Moros, Eduardo G.; Zheng, Junying; Hauer-Jensen, Martin; Boerma, Marjan

2013-01-01

13

Roles of Sensory Nerves in the Regulation of Radiation-Induced Structural and Functional Changes in the Heart  

SciTech Connect

Purpose: Radiation-induced heart disease (RIHD) is a chronic severe side effect of radiation therapy of intrathoracic and chest wall tumors. The heart contains a dense network of sensory neurons that not only are involved in monitoring of cardiac events such as ischemia and reperfusion but also play a role in cardiac tissue homeostasis, preconditioning, and repair. The purpose of this study was to examine the role of sensory nerves in RIHD. Methods and Materials: Male Sprague-Dawley rats were administered capsaicin to permanently ablate sensory nerves, 2 weeks before local image-guided heart x-ray irradiation with a single dose of 21 Gy. During the 6 months of follow-up, heart function was assessed with high-resolution echocardiography. At 6 months after irradiation, cardiac structural and molecular changes were examined with histology, immunohistochemistry, and Western blot analysis. Results: Capsaicin pretreatment blunted the effects of radiation on myocardial fibrosis and mast cell infiltration and activity. By contrast, capsaicin pretreatment caused a small but significant reduction in cardiac output 6 months after irradiation. Capsaicin did not alter the effects of radiation on cardiac macrophage number or indicators of autophagy and apoptosis. Conclusions: These results suggest that sensory nerves, although they play a predominantly protective role in radiation-induced cardiac function changes, may eventually enhance radiation-induced myocardial fibrosis and mast cell activity.

Sridharan, Vijayalakshmi; Tripathi, Preeti [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Sharma, Sunil [Department of Radiation Oncology, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Moros, Eduardo G. [Department of Radiation Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Zheng, Junying [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Hauer-Jensen, Martin [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Surgical Service, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas (United States); Boerma, Marjan, E-mail: mboerma@uams.edu [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States)

2014-01-01

14

Pharmacologic rescue of motor and sensory function by the neuroprotective compound P7C3 following neonatal nerve injury.  

PubMed

Nerve injuries cause pain, paralysis and numbness that can lead to major disability, and newborns often sustain nerve injuries during delivery that result in lifelong impairment. Without a pharmacologic agent to enhance functional recovery from these injuries, clinicians rely solely on surgery and rehabilitation to treat patients. Unfortunately, patient outcomes remain poor despite application of the most advanced microsurgical and rehabilitative techniques. We hypothesized that the detrimental effects of traumatic neonatal nerve injury could be mitigated with pharmacologic neuroprotection, and tested whether the novel neuroprotective agent P7C3 would block peripheral neuron cell death and enhance functional recovery in a rat neonatal nerve injury model. Administration of P7C3 after sciatic nerve crush injury doubled motor and sensory neuron survival, and also promoted axon regeneration in a dose-dependent manner. Treatment with P7C3 also enhanced behavioral and muscle functional recovery, and reversed pathological mobilization of spinal microglia after injury. Our findings suggest that the P7C3 family of neuroprotective compounds may provide a basis for the development of a new neuroprotective drug to enhance recovery following peripheral nerve injury. PMID:25313000

Kemp, S W P; Szynkaruk, M; Stanoulis, K N; Wood, M D; Liu, E H; Willand, M P; Morlock, L; Naidoo, J; Williams, N S; Ready, J M; Mangano, T J; Beggs, S; Salter, M W; Gordon, T; Pieper, A A; Borschel, G H

2015-01-22

15

Age-related changes in sympathetic modulation of sensory nerve activity in rat skin  

Microsoft Academic Search

Objectives: Sensory nerves play an important role in mediating neurogenic inflammation and subsequent tissue healing. A decrease in sensory nerve function with increasing age has been reported to correlate with poor tissue healing. Sympathetic nerves are known to modulate sensory nerve function, and changes in this modulation could also have important implications with ageing. The aims of this study were

M. Merhi; R. D. Helme; Z. Khalil

1998-01-01

16

Nitric oxide-releasing aspirin protects gastric mucosa against ethanol damage in rats with functional ablation of sensory nerves  

Microsoft Academic Search

Objective and Design: The aim of the present study was to investigate, whether sensory nerves are involved in the gastroprotection induced by NO releasing non-steroidal anti-inflammatory drugs (NO-NSAID). Material: Studies were performed in Wistar rats with intact or inactivated sensory nerves by pretreatment with large dose of capsaicin (125 mg\\/kg sc). Treatments: Acute gastric lesions were induced by 100% ethanol

P. C. Konturek; T. Brzozowski; J. Kania; S. J. Konturek; E. G. Hahn

2003-01-01

17

Capsaicin-sensitive sensory nerves exert complex regulatory functions in the serum-transfer mouse model of autoimmune arthritis  

PubMed Central

Objective The K/BxN serum-transfer arthritis is a widely-used translational mouse model of rheumatoid arthritis, in which the immunological components have thoroughly been investigated. In contrast, little is known about the role of sensory neural factors and the complexity of neuro–immune interactions. Therefore, we analyzed the involvement of capsaicin-sensitive peptidergic sensory nerves in autoantibody-induced arthritis with integrative methodology. Methods Arthritogenic K/BxN or control serum was injected to non-pretreated mice or resiniferatoxin (RTX)-pretreated animals where capsaicin-sensitive nerves were inactivated. Edema, touch sensitivity, noxious heat threshold, joint function, body weight and clinical arthritis severity scores were determined repeatedly throughout two weeks. Micro-CT and in vivo optical imaging to determine matrix-metalloproteinase (MMP) and neutrophil-derived myeloperoxidase (MPO) activities, semiquantitative histopathological scoring and radioimmunoassay to measure somatostatin in the joint homogenates were also performed. Results In RTX-pretreated mice, the autoantibody-induced joint swelling, arthritis severity score, MMP and MPO activities, as well as histopathological alterations were significantly greater compared to non-pretreated animals. Self-control quantification of the bone mass revealed decreased values in intact female mice, but significantly greater arthritis-induced pathological bone formation after RTX-pretreatment. In contrast, mechanical hyperalgesia from day 10 was smaller after inactivating capsaicin-sensitive afferents. Although thermal hyperalgesia did not develop, noxious heat threshold was significantly higher following RTX pretreatment. Somatostatin-like immunoreactivity elevated in the tibiotarsal joints in non-pretreated, which was significantly less in RTX-pretreated mice. Conclusions Although capsaicin-sensitive sensory nerves mediate mechanical hyperalgesia in the later phase of autoantibody-induced chronic arthritis, they play important anti-inflammatory roles at least partially through somatostatin release. PMID:25524130

Borbély, Éva; Botz, Bálint; Bölcskei, Kata; Kenyér, Tibor; Kereskai, László; Kiss, Tamás; Szolcsányi, János; Pintér, Erika; Csepregi, Janka Zsófia; Mócsai, Attila; Helyes, Zsuzsanna

2015-01-01

18

Differential motor and sensory functional recovery in male but not female adult rats is associated with remyelination rather than axon regeneration after sciatic nerve crush.  

PubMed

Peripheral nerve functional recovery after injuries relies on both axon regeneration and remyelination. Both axon regeneration and remyelination require intimate interactions between regenerating neurons and their accompanying Schwann cells. Previous studies have shown that motor and sensory neurons are intrinsically different in their regeneration potentials. Moreover, denervated Schwann cells accompanying myelinated motor and sensory axons have distinct gene expression profiles for regeneration-associated growth factors. However, it is unknown whether differential motor and sensory functional recovery exists. If so, the particular one among axon regeneration and remyelination responsible for this difference remains unclear. Here, we aimed to establish an adult rat sciatic nerve crush model with the nonserrated microneedle holders and measured rat motor and sensory functions during regeneration. Furthermore, axon regeneration and remyelination was evaluated by morphometric analysis of electron microscopic images on the basis of nerve fiber classification. Our results showed that A? fiber-mediated motor function was successfully recovered in both male and female rats. A? fiber-mediated sensory function was partially restored in male rats, but completely recovered in female littermates. For both male and female rats, the numbers of regenerated motor and sensory axons were quite comparable. However, remyelination was diverse among myelinated motor and sensory nerve fibers. In detail, A? and A? fibers incompletely remyelinated in male, but not female rats, whereas A? fibers fully remyelinated in both sexes. Our result indicated that differential motor and sensory functional recovery in male but not female adult rats is associated with remyelination rather than axon regeneration after sciatic nerve crush. PMID:25830493

Tong, Ling-Ling; Ding, You-Quan; Jing, Hong-Bo; Li, Xuan-Yang; Qi, Jian-Guo

2015-05-01

19

Natural history of sensory nerve recovery after cutaneous nerve injury following foot and ankle surgery  

PubMed Central

Cutaneous nerve injury is the most common complication following foot and ankle surgery. However, clinical studies including long-term follow-up data after cutaneous nerve injury of the foot and ankle are lacking. In the current retrospective study, we analyzed the clinical data of 279 patients who underwent foot and ankle surgery. Subjects who suffered from apparent paresthesia in the cutaneous sensory nerve area after surgery were included in the study. Patients received oral vitamin B12 and methylcobalamin. We examined final follow-up data of 17 patients, including seven with sural nerve injury, five with superficial peroneal nerve injury, and five with plantar medial cutaneous nerve injury. We assessed nerve sensory function using the Medical Research Council Scale. Follow-up immediately, at 6 weeks, 3, 6 and 9 months, and 1 year after surgery demonstrated that sensory function was gradually restored in most patients within 6 months. However, recovery was slow at 9 months. There was no significant difference in sensory function between 9 months and 1 year after surgery. Painful neuromas occurred in four patients at 9 months to 1 year. The results demonstrated that the recovery of sensory function in patients with various cutaneous nerve injuries after foot and ankle surgery required at least 6 months.

Bai, Lu; Han, Yan-ni; Zhang, Wen-tao; Huang, Wei; Zhang, Hong-lei

2015-01-01

20

Protein expression of sensory and motor nerves  

PubMed Central

The present study utilized samples from bilateral motor branches of the femoral nerve, as well as saphenous nerves, ventral roots, and dorsal roots of the spinal cord, to detect differential protein expression using two-dimensional gel electrophoresis and nano ultra-high performance liquid chromatography electrospray ionization mass spectrometry tandem mass spectrometry techniques. A mass spectrum was identified using the Mascot search. Results revealed differential expression of 11 proteins, including transgelin, Ig kappa chain precursor, plasma glutathione peroxidase precursor, an unnamed protein product (gi|55628), glyceraldehyde-3-phosphate dehydrogenase-like protein, lactoylglutathione lyase, adenylate kinase isozyme 1, two unnamed proteins products (gi|55628 and gi|1334163), and poly(rC)-binding protein 1 in motor and sensory nerves. Results suggested that these proteins played roles in specific nerve regeneration following peripheral nerve injury and served as specific markers for motor and sensory nerves.

Ren, Zhiwu; Wang, Yu; Peng, Jiang; Zhang, Li; Xu, Wenjing; Liang, Xiangdang; Zhao, Qing; Lu, Shibi

2012-01-01

21

The Anatomy and Function of 'Free' Nerve Endings in an Amphibian Skin Sensory System  

Microsoft Academic Search

The skin of the body and tail in embryonic and young larval Xenopus is innervated by sensory neurones with cell bodies lying along the dorsal midline of the spinal cord. These Rohon-Beard cells have naked peripheral neurites, usually under 1 mu m in diameter, which form a loose network under the skin. In the electron microscope narrower neurites from this

Alan Roberts; B. P. Hayes

1977-01-01

22

Regulating cough through modulation of sensory nerve function in the airways.  

PubMed

Whilst local anaesthetics when applied directly to laryngeal nerves or topically to the lung can suppress cough, their chronic use is constrained because of dose limiting side effects. However, the effectiveness of local anaesthetics suggests that selectivity targeting nerves in the airway may provide novel approaches for the treatment of cough in the future. There is a considerable wealth of evidence showing that there are different afferent nerve subtypes in the airways. Traditionally C-fibres have been the focus of much research in the cough field since the stimulation of these afferents by capsaicin is able to elicit cough in guinea-pigs and in man, and drugs targeting various proteins expressed in these nerves (e.g. mu-opioid, NOP1, TRPV1, sodium channels) have been shown to be anti-tussive in preclinical models of cough. However, interest in A? fibres has increased recently in light of the discovery of a specific cough receptor in the guinea-pig that is provoked by citric acid and punctate stimulation, but not capsaicin and which has been anatomically linked to A? fibres. There is also some evidence that as a result of inflammation in the airways, A? fibres can begin to express neuropeptides and TRPV1 receptors so that they can become responsive to endogenous activators of this ion channel and to irritants like capsaicin. Consequently, there is considerable interest in targeting either one or both afferent nerve types for the treatment of chronic cough. However, to date the translation of preclinical studies into man has largely been disappointing and certainly there is a need for better preclinical models in this field. There also remain many challenges to overcome at a clinical level, such as what patient group(s) should be used to assess anti-tussive drugs and whether the use of irritants that induce cough in healthy volunteers (such as citric acid or capsaicin) is of any value in the assessment of novel anti-tussive drugs. The development of several continuous monitoring methodologies for measuring cough will hopefully allow better evaluation of treatments in patients with chronic cough. Nonetheless, cough remains a major unmet clinical need in respiratory medicine where new drugs are urgently required. PMID:23524012

Spina, D; Page, C P

2013-10-01

23

Sensory nerve action potentials and sensory perception in women with arthritis of the hand  

PubMed Central

Background Arthritis of the hand can limit a person’s ability to perform daily activities. Whether or not sensory deficits contribute to the disability in this population remains unknown. The primary purpose of this study was to determine if women with osteoarthritis (OA) or rheumatoid arthritis (RA) of the hand have sensory impairments. Methods Sensory function in the dominant hand of women with hand OA or RA and healthy women was evaluated by measuring sensory nerve action potentials (SNAPs) from the median, ulnar and radial nerves, sensory mapping (SM), and vibratory and current perception thresholds (VPT and CPT, respectively) of the second and fifth digits. Results All SNAP amplitudes were significantly lower for the hand OA and hand RA groups compared with the healthy group (p?sensory fibers in the median, ulnar and radial nerves. Less apparent were losses in conduction speed or sensory perception. PMID:22575001

2012-01-01

24

Peripheral nerve function in chronic liver disease  

Microsoft Academic Search

Peripheral nerve function has been studied in 50 patients with chronic liver disease. An increase in the latency or a reduction in the response amplitude of the evoked sensory potential of the median nerve was detected in 34 of the 50 subjects. This was in striking contrast to the paucity of neurological signs and symptoms suggestive of peripheral nerve damage

K. N. Seneviratne; O. A. Peiris

1970-01-01

25

Leptin-sensitive sensory nerves innervate white fat  

PubMed Central

Leptin, the primary white adipose tissue (WAT) adipokine, is thought to convey lipid reserve information to the brain via the circulation. Because WAT responds to environmental/internal signals in a fat pad-specific (FPS) manner, systemic signals such as leptin would fail to communicate such distinctive information. Saturation of brain leptin transport systems also would fail to convey increased lipid levels beyond that point. WAT possesses sensory innervation exemplified by proven sensory-associated peptides in nerves within the tissue and by viral sensory nerve-specific transneuronal tract tracer, H129 strain of herpes simplex virus 1 labeling of dorsal root ganglia (DRG) pseudounipolar neurons, spinal cord and central sensory circuits. Leptin as a paracrine factor activating WAT sensory innervation could supply the brain with FPS information. Therefore, we tested for and found the presence of the long form of the leptin receptor (Ob-Rb) on DRG pseudounipolar neurons immunohistochemically labeled after injections of Fluorogold, a retrograde tract tracer, into inguinal WAT (IWAT). Intra-IWAT leptin injections (300 ng) significantly elevated IWAT nerve spike rate within 5 min and persisted for at least 30 min. Intra-IWAT leptin injections also induced significant c-Fos immunoreactivity (ir), indicating neural activation across DRG pseudounipolar sensory neurons labeled with Fluorogold IWAT injections. Intraperitoneal leptin injection did not increase c-Fos-ir in DRG or the arcuate nucleus, nor did it increase arcuate signal transducer and activator of transcription 3 phosphorylation-ir. Collectively, these results strongly suggest that endogenous leptin secreted from white adipocytes functions as a paracrine factor to activate spinal sensory nerves innervating the tissue. PMID:23612999

Murphy, Keegan T.; Schwartz, Gary J.; Nguyen, Ngoc Ly T.; Mendez, Jennifer M.; Ryu, Vitaly

2013-01-01

26

Reduced intraepidermal nerve fiber density in HIV-associated sensory  

E-print Network

Reduced intraepidermal nerve fiber density in HIV-associated sensory neuropathy M. Polydefkis, MD nerve fiber (IENF) density in HIV-associated sensory neuropathy (HIV-SN) to measurements of neuropathy density determination has emerged as a diagnostic test for patients with small-fiber sensory neuropathy

Steinbach, Joe Henry

27

Sensory capacity of reinnervated skin after redirection of amputated upper limb nerves to the chest  

Microsoft Academic Search

Targeted reinnervation is a new neural-machine interface that has been developed to help improve the function of new- generation prosthetic limbs. Targeted reinnervation is a surgical procedure that takes the nerves that once innervated a severed limb and redirects them to proximal muscle and skin sites. The sensory afferents of the redirected nerves reinnervate the skin overlying the transfer site.

Paul D. Marasco; Aimee E. Schultz; Todd A. Kuiken

2009-01-01

28

Parkinson Disease Affects Peripheral Sensory Nerves in the Pharynx  

PubMed Central

Dysphagia is very common in patients with Parkinson’s disease (PD) and often leads to aspiration pneumonia, the most common cause of death in PD. Unfortunately, current therapies are largely ineffective for dysphagia. As pharyngeal sensation normally triggers the swallowing reflex, we examined pharyngeal sensory nerves in PD for Lewy pathology. Sensory nerves supplying the pharynx were excised from autopsied pharynges obtained from patients with clinically diagnosed and neuropathologically confirmed PD (n = 10) and healthy age-matched controls (n = 4). We examined: the glossopharyngeal nerve (IX); the pharyngeal sensory branch of the vagus nerve (PSB-X); and the internal superior laryngeal nerve (ISLN) innervating the laryngopharynx. Immunohistochemistry for phosphorylated ?-synuclein was used to detect potential Lewy pathology. Axonal ?-synuclein aggregates in the pharyngeal sensory nerves were identified in all of the PD subjects but not in the controls. The density of ?-synuclein-positive lesions was significantly greater in PD subjects with documented dysphagia compared to those without dysphagia. In addition, ?-synuclein-immunoreactive nerve fibers in the ISLN were much more abundant than those in the IX and PSBX. These findings suggest that pharyngeal sensory nerves are directly affected by the pathologic process of PD. This anatomic pathology may decrease pharyngeal sensation impairing swallowing and airway protective reflexes, thereby contributing to dysphagia and aspiration. PMID:23771215

Mu, Liancai; Sobotka, Stanislaw; Chen, Jingming; Su, Hungxi; Sanders, Ira; Nyirenda, Themba; Adler, Charles H.; Shill, Holly A.; Caviness, John N.; Samanta, Johan E.; Sue, Lucia I.; Beach, Thomas G.

2013-01-01

29

Sensory enrichment after peripheral nerve injury restores cortical, not thalamic, receptive field organization.  

PubMed

Sensory perception can be severely degraded after peripheral injuries that disrupt the functional organization of the sensory maps in somatosensory cortex, even after nerve regeneration has occurred. Rehabilitation involving sensory retraining can improve perceptual function, presumably through plasticity mechanisms in the somatosensory processing network. However, virtually nothing is known about the effects of rehabilitation strategies on brain organization, or where the effects are mediated. In this study, five macaque monkeys received months of enriched sensory experience after median nerve cut and repair early in life. Subsequently, the sensory representation of the hand in primary somatosensory cortex was mapped using multiunit microelectrodes. Additionally, the primary somatosensory relay in the thalamus, the ventroposterior nucleus, was studied to determine whether the effects of the enrichment were initiated subcortically or cortically. Age-matched controls included six monkeys with no sensory manipulation after median nerve cut and regeneration, and one monkey that had restricted sensory experience after the injury. The most substantial effect of the sensory environment was on receptive field sizes in cortical area 3b. Significantly greater proportions of cortical receptive fields in the enriched monkeys were small and well localized compared to the controls, which showed higher proportions of abnormally large or disorganized fields. The refinements in receptive field size and extent in somatosensory cortex likely provide better resolution in the sensory map and may explain the improved functional outcomes after rehabilitation in humans. PMID:11359527

Florence, S L; Boydston, L A; Hackett, T A; Lachoff, H T; Strata, F; Niblock, M M

2001-05-01

30

Intrafascicular stimulation of monkey arm nerves evokes coordinated grasp and sensory responses.  

PubMed

High-count microelectrode arrays implanted in peripheral nerves could restore motor function after spinal cord injury or sensory function after limb loss. In this study, we implanted Utah Slanted Electrode Arrays (USEAs) intrafascicularly at the elbow or shoulder in arm nerves of rhesus monkeys (n = 4) under isoflurane anesthesia. Input-output curves indicated that pulse-width-modulated single-electrode stimulation in each arm nerve could recruit single muscles with little or no recruitment of other muscles. Stimulus trains evoked specific, natural, hand movements, which could be combined via multielectrode stimulation to elicit coordinated power or pinch grasp. Stimulation also elicited short-latency evoked potentials (EPs) in primary somatosensory cortex, which might be used to provide sensory feedback from a prosthetic limb. These results demonstrate a high-resolution, high-channel-count interface to the peripheral nervous system for restoring hand function after neural injury or disruption or for examining nerve structure. PMID:23076108

Ledbetter, Noah M; Ethier, Christian; Oby, Emily R; Hiatt, Scott D; Wilder, Andrew M; Ko, Jason H; Agnew, Sonya P; Miller, Lee E; Clark, Gregory A

2013-01-01

31

Intrafascicular stimulation of monkey arm nerves evokes coordinated grasp and sensory responses  

PubMed Central

High-count microelectrode arrays implanted in peripheral nerves could restore motor function after spinal cord injury or sensory function after limb loss. In this study, we implanted Utah Slanted Electrode Arrays (USEAs) intrafascicularly at the elbow or shoulder in arm nerves of rhesus monkeys (n = 4) under isoflurane anesthesia. Input-output curves indicated that pulse-width-modulated single-electrode stimulation in each arm nerve could recruit single muscles with little or no recruitment of other muscles. Stimulus trains evoked specific, natural, hand movements, which could be combined via multielectrode stimulation to elicit coordinated power or pinch grasp. Stimulation also elicited short-latency evoked potentials (EPs) in primary somatosensory cortex, which might be used to provide sensory feedback from a prosthetic limb. These results demonstrate a high-resolution, high-channel-count interface to the peripheral nervous system for restoring hand function after neural injury or disruption or for examining nerve structure. PMID:23076108

Ledbetter, Noah M.; Ethier, Christian; Oby, Emily R.; Hiatt, Scott D.; Wilder, Andrew M.; Ko, Jason H.; Agnew, Sonya P.; Miller, Lee E.

2013-01-01

32

A reversible functional sensory neuropathy model.  

PubMed

Small-fiber neuropathy was induced in young adult mice by intraperitoneal injection of resiniferatoxin (RTX), a TRPV1 agonist. At day 7, RTX induced significant thermal and mechanical hypoalgesia. At day 28, mechanical and thermal nociception were restored. No nerve degeneration in skin was observed and unmyelinated nerve fiber morphology and density in sciatic nerve were unchanged. At day 7, substance P (SP) was largely depleted in dorsal root ganglia (DRG) neurons, although calcitonin gene-related peptide (CGRP) was only moderately depleted. Three weeks after, SP and CGRP expression was restored in DRG neurons. At the same time, CGRP expression remained low in intraepidermal nerve fibers (IENFs) whereas SP expression had improved. In summary, RTX induced in our model a transient neuropeptide depletion in sensory neurons without nerve degeneration. We think this model is valuable as it brings the opportunity to study functional nerve changes in the very early phase of small fiber neuropathy. Moreover, it may represent a useful tool to study the mechanisms of action of therapeutic strategies to prevent sensory neuropathy of various origins. PMID:24792390

Danigo, Aurore; Magy, Laurent; Richard, Laurence; Sturtz, Franck; Funalot, Benoît; Demiot, Claire

2014-06-13

33

Sensory reinnervation of muscle spindles after repair of tibial nerve defects using autogenous vein grafts  

PubMed Central

Motor reinnervation after repair of tibial nerve defects using autologous vein grafts in rats has previously been reported, but sensory reinnervation after the same repair has not been fully investigated. In this study, partial sensory reinnervation of muscle spindles was observed after repair of 10-mm left tibial nerve defects using autologous vein grafts with end-to-end anastomosis in rats, and functional recovery was confirmed by electrophysiological studies. There were no significant differences in the number, size, or electrophysiological function of reinnervated muscle spindles between the two experimental groups. These findings suggest that repair of short nerve defects with autologous vein grafts provides comparable results to immediate end-to-end anastomosis in terms of sensory reinnervation of muscle spindles. PMID:25206863

Pang, Youwang; Hong, Qingnan; Zheng, Jinan

2014-01-01

34

Motor and sensory conduction in the musculocutaneous nerve.  

PubMed Central

Motor and sensory conduction velocity in the musculocutaneous nerve were determined in 51 normal subjects. The maximal velocity from the anterior cervical triangle to the axilla was the same in motor and sensory fibres. The conduction velocity decreased 2m/s per 10 years increase of age. It was 70 m/s at 15-24 years and 58 m/s at 65-74 years. The velocity of the slowest components in sensory fibres was 17 m/s. Three selected case reports illustrate the diagnostic value of the method. Images PMID:993811

Trojaborg, W

1976-01-01

35

Recording sensory and motor information from peripheral nerves with Utah Slanted Electrode Arrays  

Microsoft Academic Search

Recording and stimulation via high-count penetrating microelectrode arrays implanted in peripheral nerves may help restore precise motor and sensory function after nervous system damage or disease. Although previous work has demonstrated safety and relatively successful stimulation for long-term implants of 100-electrode Utah Slanted Electrode Arrays (USEAs) in feline sciatic nerve [1], two major remaining challenges were 1) to maintain viable

Gregory A. Clark; Noah M. Ledbetter; David J. Warren; Reid R. Harrison

2011-01-01

36

Sensory Nerves as Modulators of Cutaneous Inflammatory Reactions in Health and Disease  

Microsoft Academic Search

Chemosensitive afferent nerves expressing the capsaicin\\/TRPV1 (transient receptor potential vanilloid receptor-1) receptor are not only involved in the transmission of nociceptive impulses toward the central nervous system, but also play pivotal roles in the initiation and modulation of vascular, inflammatory, and immune reactions in a variety of organs, including the skin. These sensory nerves exert their efferent\\/local regulatory functions primarily

Gábor Jancsó; Márta katona; Viktor Horváth; Péter Sántha; József Nagy

2009-01-01

37

Inhibition of Rho-kinase differentially affects axon regeneration of peripheral motor and sensory nerves.  

PubMed

The small GTPase RhoA and its down-stream effector Rho-kinase (ROCK) are important effector molecules of the neuronal cytoskeleton. Modulation of the RhoA/ROCK pathway has been shown to promote axonal regeneration, however in vitro and animal studies are inconsistent regarding the extent of axonal outgrowth induced by pharmacological inhibition of ROCK. We hypothesized that injury to sensory and motor nerves result in diverse activation levels of RhoA, which may impact the response of those nerve fiber modalities to ROCK inhibition. We therefore examined the effects of Y-27632, a chemical ROCK inhibitor, on the axonal outgrowth of peripheral sensory and motor neurons grown in the presence of growth-inhibiting chondroitin sulfate proteoglycans (CSPGs). In addition we examined the effects of three different doses of Y-27632 on nerve regeneration of motor and sensory nerves in animal models of peripheral nerve crush. In vitro, sensory neurons were less responsive to Y-27632 compared to motor neurons in a non-growth permissive environment. These differences were associated with altered expression and activation of RhoA in sensory and motor axons. In vivo, systemic treatment with high doses of Y-27632 significantly enhanced the regeneration of motor axons over short distances, while the regeneration of sensory fibers remained largely unchanged. Our results support the concept that in a growth non-permissive environment, the regenerative capacity of sensory and motor axons is differentially affected by the RhoA/ROCK pathway, with motor neurons being more responsive compared to sensory. Future treatments, that are aimed to modulate RhoA activity, should consider this functional diversity. PMID:25261755

Joshi, Abhijeet R; Bobylev, Ilja; Zhang, Gang; Sheikh, Kazim A; Lehmann, Helmar C

2015-01-01

38

Sensory nerve impairment following mandibular third molar surgery  

Microsoft Academic Search

Purpose: This prospective study reports the rate and factors influencing sensory impairment of the inferior alveolar and lingual nerves after the removal of impacted mandibular third molars under local anesthesia. Patients and Methods: There were 741 patients with 741 mandibular third molars removed under local anesthesia during a 3-year period from 1994 to 1997. Standardized data collection included the patient's

Anwar B Bataineh

2001-01-01

39

Factors predicting sensory and motor recovery after the repair of upper limb peripheral nerve injuries  

PubMed Central

OBJECTIVE: To investigate the factors associated with sensory and motor recovery after the repair of upper limb peripheral nerve injuries. DATA SOURCES: The online PubMed database was searched for English articles describing outcomes after the repair of median, ulnar, radial, and digital nerve injuries in humans with a publication date between 1 January 1990 and 16 February 2011. STUDY SELECTION: The following types of article were selected: (1) clinical trials describing the repair of median, ulnar, radial, and digital nerve injuries published in English; and (2) studies that reported sufficient patient information, including age, mechanism of injury, nerve injured, injury location, defect length, repair time, repair method, and repair materials. SPSS 13.0 software was used to perform univariate and multivariate logistic regression analyses and to investigate the patient and intervention factors associated with outcomes. MAIN OUTCOME MEASURES: Sensory function was assessed using the Mackinnon-Dellon scale and motor function was assessed using the manual muscle test. Satisfactory motor recovery was defined as grade M4 or M5, and satisfactory sensory recovery was defined as grade S3+ or S4. RESULTS: Seventy-one articles were included in this study. Univariate and multivariate logistic regression analyses showed that repair time, repair materials, and nerve injured were independent predictors of outcome after the repair of nerve injuries (P < 0.05), and that the nerve injured was the main factor affecting the rate of good to excellent recovery. CONCLUSION: Predictors of outcome after the repair of peripheral nerve injuries include age, gender, repair time, repair materials, nerve injured, defect length, and duration of follow-up. PMID:25206870

He, Bo; Zhu, Zhaowei; Zhu, Qingtang; Zhou, Xiang; Zheng, Canbin; Li, Pengliang; Zhu, Shuang; Liu, Xiaolin; Zhu, Jiakai

2014-01-01

40

Noninvasive Peroneal Sensory and Motor Nerve Conduction Recordings in the Rabbit Distal Hindlimb: Feasibility, Variability and Neuropathy Measure  

PubMed Central

The peroneal nerve anatomy of the rabbit distal hindlimb is similar to humans, but reports of distal peroneal nerve conduction studies were not identified with a literature search. Distal sensorimotor recordings may be useful for studying rabbit models of length-dependent peripheral neuropathy. Surface electrodes were adhered to the dorsal rabbit foot overlying the extensor digitorum brevis muscle and the superficial peroneal nerve. The deep and superficial peroneal nerves were stimulated above the ankle and the common peroneal nerve was stimulated at the knee. The nerve conduction studies were repeated twice with a one-week intertest interval to determine measurement variability. Intravenous vincristine was used to produce a peripheral neuropathy. Repeat recordings measured the response to vincristine. A compound muscle action potential and a sensory nerve action potential were evoked in all rabbits. The compound muscle action potential mean amplitude was 0.29 mV (SD ± 0.12) and the fibula head to ankle mean motor conduction velocity was 46.5 m/s (SD ± 2.9). The sensory nerve action potential mean amplitude was 22.8 ?V (SD ± 2.8) and the distal sensory conduction velocity was 38.8 m/s (SD ± 2.2). Sensorimotor latencies and velocities were least variable between two test sessions (coefficient of variation ?=? 2.6–5.9%), sensory potential amplitudes were intermediate (coefficient of variation ?=? 11.1%) and compound potential amplitudes were the most variable (coefficient of variation ?=?19.3%). Vincristine abolished compound muscle action potentials and reduced sensory nerve action potential amplitudes by 42–57% while having little effect on velocity. Rabbit distal hindlimb nerve conduction studies are feasible with surface recordings and stimulation. The evoked distal sensory potentials have amplitudes, configurations and recording techniques that are similar to humans and may be valuable for measuring large sensory fiber function in chronic models of peripheral neuropathies. PMID:24658286

Hotson, John R.

2014-01-01

41

Regeneration of sensory but not motor axons following visceral nerve injury.  

PubMed

Following peripheral nerve injury, restoration of function may occur via the regeneration of injured axons or compensatory sprouting of spared axons. Injury to visceral nerves that control urogenital organs is a common consequence of pelvic surgery, however their capacity to reinnervate organs is poorly understood. To determine if and how sensory and motor connections to the bladder are re-established, a novel surgical model of visceral nerve injury was performed unilaterally in adult male Wistar rats. Bladder-projecting motor and sensory neurons in pelvic ganglia and lumbosacral dorsal root ganglia, respectively, were identified and characterised by retrograde tracing and immunofluorescence. Application of tracers ipsi- and contralateral to injury distinguished the projection pathways of new connections in the bladder. In naive animals, the majority of sensory and motor neurons project ipsilaterally to the bladder, while ~20 % project contralaterally and ~5 % bilaterally. Injured axons of motor neurons were unable to regenerate by 4weeks after transection. In contrast, by this time many injured sensory neurons regrew axons to reform a substantial plexus within the detrusor and suburothelial tissues. These regeneration responses were also indicated by upregulation of activating transcription factor-3 (ATF-3), which was sustained in motor neurons but transient in sensory bladder-projecting neurons. Axotomy had little or no effect on the survival of bladder-projecting sensory and motor neurons. We also found evidence that uninjured motor and sensory neurons develop additional projections to the denervated bladder tissue and return connectivity, likely by undergoing compensatory growth. In conclusion, our results show that visceral sensory and motor neurons have a different capacity to regenerate axons following axotomy, however in both components of the circuit uninjured bladder neurons spontaneously grow new axon collaterals to replace the lost terminal field within the organ. For a full functional recovery, understanding the environmental and cellular mechanisms that reduce the ability of pelvic ganglion cells to undergo axonal regeneration is needed. PMID:25725351

Payne, Sophie C; Belleville, Philip J; Keast, Janet R

2015-04-01

42

Sensory nerve conduction velocities of median, ulnar and radial nerves in patients with vibration syndrome  

Microsoft Academic Search

Objective  The present study aimed to clarify the range of involvement for hand-arm vibration syndrome (VS) in the median, ulnar and\\u000a radial nerves of the hand.\\u000a \\u000a \\u000a \\u000a Methods  Sensory nerve conduction velocities (SCVs) for 3 nerves in the hands and arms were examined for 34 patients with VS and 23\\u000a age-matched controls. Neuropathy types were classified by possible carpal tunnel syndrome (CTS), Guyon’s

Mamoru Hirata; Hisataka Sakakibara

2007-01-01

43

Diagnostic specificity of sensory and motor nerve conduction variables in early detection of carpal tunnel syndrome  

Microsoft Academic Search

In the carpal tunnel syndrome (CTS) sensory nerve conduction is more sensitive than motor conduction. However, 8%–25% of the sensory distal latencies in symptomatic hands may still be normal. A systematic study was made of the median, ulnar and radial orthodromic nerve conduction velocities (SNCV) stimulating each of the fingers separately. Four SNCVs from the median nerve, two SNCVs from

R. Cioni; S. Passero; C. Paradiso; F. Giannini; N. Battistini; G. Rushworth

1989-01-01

44

Functional weakness and sensory disturbance  

PubMed Central

In the diagnosis of functional weakness and sensory disturbance, positive physical signs are as important as absence of signs of disease. Motor signs, particularly Hoover's sign, are more reliable than sensory signs, but none should be used in isolation and must be interpreted in the overall context of the presentation. It should be borne in mind that a patient may have both a functional and an organic disorder. PMID:12185152

Stone, J; Zeman, A; Sharpe, M

2002-01-01

45

Recording sensory and motor information from peripheral nerves with Utah Slanted Electrode Arrays.  

PubMed

Recording and stimulation via high-count penetrating microelectrode arrays implanted in peripheral nerves may help restore precise motor and sensory function after nervous system damage or disease. Although previous work has demonstrated safety and relatively successful stimulation for long-term implants of 100-electrode Utah Slanted Electrode Arrays (USEAs) in feline sciatic nerve [1], two major remaining challenges were 1) to maintain viable recordings of nerve action potentials long-term, and 2) to overcome contamination of unit recordings by myoelectric (EMG) activity in awake, moving animals. In conjunction with improvements to USEAs themselves, we have redesigned several aspects of our USEA containment and connector systems. Although further increases in unit yield and long-term stability remain desirable, here we report considerable progress toward meeting both of these goals: We have successfully recorded unit activity from USEAs implanted intrafascicularly in sciatic nerve for periods up to 4 months (the terminal experimental time point), and we have developed a containment system that effectively eliminates or substantially reduces EMG contamination of unit recordings in the moving animal. In addition, we used a 100-channel wireless recording integrated circuit attached to implanted USEAs to transmit broadband or spike-threshold data from nerve. Neural data thusly obtained during imposed limb movements were decoded blindly to drive a virtual prosthetic limb in real time. These results support the possibility of using USEAs in peripheral nerves to provide motor control and cutaneous or proprioceptive sensory feedback in individuals after limb loss or spinal cord injury. PMID:22255372

Clark, Gregory A; Ledbetter, Noah M; Warren, David J; Harrison, Reid R

2011-01-01

46

Capsaicin-sensitive sensory nerve fibers contribute to the generation and maintenance of skeletal fracture pain.  

PubMed

Although skeletal pain can have a marked impact on a patient's functional status and quality of life, relatively little is known about the specific populations of peripheral nerve fibers that drive non-malignant bone pain. In the present report, neonatal male Sprague-Dawley rats were treated with capsaicin or vehicle and femoral fracture was produced when the animals were young adults (15-16 weeks old). Capsaicin treatment, but not vehicle, resulted in a significant (>70%) depletion in the density of calcitonin-gene related peptide positive (CGRP(+)) sensory nerve fibers, but not 200 kDa neurofilament H positive (NF200(+)) sensory nerve fibers in the periosteum. The periosteum is a thin, cellular and fibrous tissue that tightly adheres to the outer surface of all but the articulated surface of bone and appears to play a pivotal role in driving fracture pain. In animals treated with capsaicin, but not vehicle, there was a 50% reduction in the severity, but no change in the time course, of fracture-induced skeletal pain-related behaviors as measured by spontaneous flinching, guarding and weight bearing. These results suggest that both capsaicin-sensitive (primarily CGRP(+) C-fibers) and capsaicin-insensitive (primarily NF200(+) A-delta fibers) sensory nerve fibers participate in driving skeletal fracture pain. Skeletal pain can be a significant impediment to functional recovery following trauma-induced fracture, osteoporosis-induced fracture and orthopedic surgery procedures such as knee and hip replacement. Understanding the specific populations of sensory nerve fibers that need to be targeted to inhibit the generation and maintenance of skeletal pain may allow the development of more specific mechanism-based therapies that can effectively attenuate acute and chronic skeletal pain. PMID:19486928

Jimenez-Andrade, J M; Bloom, A P; Mantyh, W G; Koewler, N J; Freeman, K T; Delong, D; Ghilardi, J R; Kuskowski, M A; Mantyh, P W

2009-09-15

47

CAPSAICIN-SENSITIVE SENSORY NERVE FIBERS CONTRIBUTE TO THE GENERATION AND MAINTENANCE OF SKELETAL FRACTURE PAIN  

PubMed Central

Although skeletal pain can have a marked impact on a patient’s functional status and quality of life, relatively little is known about the specific populations of peripheral nerve fibers that drive non-malignant bone pain. In the present report, neonatal male Sprague Dawley rats were treated with capsaicin or vehicle and femoral fracture was produced when the animals were young adults (15–16 weeks old). Capsaicin treatment, but not vehicle, resulted in a significant (>70%) depletion in the density of calcitonin-gene related peptide positive (CGRP+) sensory nerve fibers, but not 200 kD neurofilament H positive (NF200+) sensory nerve fibers in the periosteum. The periosteum is a thin, cellular and fibrous tissue that tightly adheres to the outer surface of all but the articulated surface of bone and appears to play a pivotal role in driving fracture pain. In animals treated with capsaicin, but not vehicle, there was a 50% reduction in the severity, but no change in the time course, of fracture-induced skeletal pain related behaviors as measured by spontaneous flinching, guarding and weight bearing. These results suggest that both capsaicin-sensitive (primarily CGRP+ C-fibers) and capsaicin-insensitive (primarily NF200+ A-delta fibers) sensory nerve fibers participate in driving skeletal fracture pain. Skeletal pain can be a significant impediment to functional recovery following trauma-induced fracture, osteoporosis-induced fracture and orthopedic surgery procedures such as knee and hip replacement. Understanding the specific populations of sensory nerve fibers that need to be targeted to inhibit the generation and maintenance of skeletal pain may allow the development of more specific mechanism-based therapies that can effectively attenuate acute and chronic skeletal pain. PMID:19486928

Jimenez-Andrade, Juan Miguel; Bloom, Aaron P.; Mantyh, William G.; Koewler, Nathan J.; Freeman, Katie T.; Delong, David; Ghilardi, Joseph R.; Kuskowski, Michael A.; Mantyh, Patrick W.

2009-01-01

48

Segmental near nerve sensory conduction studies of the medical and lateral plantar nerve.  

PubMed

Tarsal Tunnel Syndrome (TTS) can be difficult to diagnose: electrophysiologic corroboration is important and has therapeutic implications. Conventional electrodiagnostic techniques are insensitive: motor latency abnormalities exist in only 52%; sensory responses are frequently absent (a nonlocalizing finding). Additionally, previously described near nerve techniques do not isolate conduction velocity (CV) measurement to the short segment across the flexor retinaculum (FR), which would theoretically improve sensitivity. We describe a technique which allows for the determination of segmental sensory CVs of the medial (MP) and lateral (LP) plantar nerves, both below (BFR) and across (AFR) the FR. Seventeen normal patients (age 22-45) were studied. Near nerve recording electrodes were positioned close to the specified nerve below and above the FR. Ring electrode stimulation (RES) of digits I (MP) or V (LP) and direct near nerve stimulation (NNS) BFR were performed. With RES digit I (n = 17), mean CV (toe to BFR) was 39.0 +/- 7.1 m/s; CV (AFR) 47.9 +/- 6.2 m/s. CV (AFR) following NNS (MP) (n = 16) was 49.4 +/- 5.1 m/s. With RES digit V (n = 10), mean CV (toe to BFR) was 36.4 +/- 3.4 m/s; CV (AFR) 57.5 +/- 6.9 m/s. CV (AFR) with NNS (LP) (n = 14) was 59.8 +/- 6.2 m/s. In conclusion, segmental MP and LP sensory CVs can be reliably obtained with near nerve technique. This approach may improve the diagnostic sensitivity of EMG in TTS. PMID:8957166

David, W S; Doyle, J J

1996-01-01

49

Peripheral injury of pelvic visceral sensory nerves alters GFR? (GDNF family receptor alpha) localization in sensory and autonomic pathways of the sacral spinal cord  

PubMed Central

GDNF (glial cell line-derived neurotrophic factor), neurturin and artemin use their co-receptors (GFR?1, GFR?2 and GFR?3, respectively) and the tyrosine kinase Ret for downstream signaling. In rodent dorsal root ganglia (DRG) most of the unmyelinated and some myelinated sensory afferents express at least one GFR?. The adult function of these receptors is not completely elucidated but their activity after peripheral nerve injury can facilitate peripheral and central axonal regeneration, recovery of sensation, and sensory hypersensitivity that contributes to pain. Our previous immunohistochemical studies of spinal cord and sciatic nerve injuries in adult rodents have identified characteristic changes in GFR?1, GFR?2 or GFR?3 in central spinal cord axons of sensory neurons located in DRG. Here we extend and contrast this analysis by studying injuries of the pelvic and hypogastric nerves that contain the majority of sensory axons projecting to the pelvic viscera (e.g., bladder and lower bowel). At 7 d, we detected some effects of pelvic but not hypogastric nerve transection on the ipsilateral spinal cord. In sacral (L6-S1) cord ipsilateral to nerve injury, GFR?1-immunoreactivity (IR) was increased in medial dorsal horn and CGRP-IR was decreased in lateral dorsal horn. Pelvic nerve injury also upregulated GFR?1- and GFR?3-IR terminals and GFR?1-IR neuronal cell bodies in the sacral parasympathetic nucleus that provides the spinal parasympathetic preganglionic output to the pelvic nerve. This evidence suggests peripheral axotomy has different effects on somatic and visceral sensory input to the spinal cord, and identifies sensory-autonomic interactions as a possible site of post-injury regulation.

Forrest, Shelley L.; Payne, Sophie C.; Keast, Janet R.; Osborne, Peregrine B.

2015-01-01

50

Sickle cell disease in mice is associated with sensitization of sensory nerve fibers.  

PubMed

The pain phenotype in sickle cell disease (SCD) patients is highly variable. A small percentage of SCD patients experience many vaso-occlusive crises/year, 5% of patients account for over 30% of pain episodes, while 39% report few episodes of severe pain. Clearly, a better understanding of the pathobiology of SCD is needed to improve its therapy. Humanized sickle cell mice recapitulate several phenotypes of SCD patients and provide a model for the study of SCD pain. Researchers have shown that one strain of humanized SCD mice, the BERK strain, has abnormal pain phenotype. However, the nociception phenotype of another humanized SCD mouse strain, the Townes strain, has not been described. In a large cross-sectional study of BERK and Townes SCD mice, we examined thermosensory response and sensory nerve fiber function using sine-wave electrical stimulation at 2000, 250, and 5?Hz to stimulate preferentially A?, A?, and C sensory nerve fibers, respectively. We found that BERK and Townes mice, compared to respective controls, had decreases in 2000, 250, and 5?Hz current vocalization thresholds in patterns that suggest sensitization of a broad spectrum of sensory nerve fibers. In addition, the pattern of sensitization of sensory fibers varied according to strain, sex, age, and mouse genotype. In a similarly variable pattern, Townes and BERKs also had significantly altered sensitivity to noxious thermal stimuli in agreement with what has been shown by others. In summary, the analysis of somatosensory function using sine-wave electrical stimulation in humanized sickle cell mice suggests that in SCD, both myelinated and unmyelinated, fibers are sensitized. The pattern of sensory fiber sensitization is distinct from that observed in pain models of neuropathic and inflammatory pain. These findings raise the possibility that sensitization of a broad spectrum of sensory fibers might contribute to the altered and variable nociception phenotype in SCD. PMID:25070860

Kenyon, Nicholas; Wang, Li; Spornick, Nicholas; Khaibullina, Alfia; Almeida, Luis Ef; Cheng, Yao; Wang, Jichuan; Guptill, Virginia; Finkel, Julia C; Quezado, Zenaide M N

2015-01-01

51

Uses of Skin Biopsy for Sensory and Autonomic Nerve Assessment  

PubMed Central

Skin biopsy is a valuable diagnostic tool for small-fiber-predominant neuropathy by the quantification of intra-epidermal nerve fiber density (IENFD). It has the unique advantage of being a minimally invasive procedure with the potential for longitudinal evaluation of both sensory and autonomic fibers. Unmyelinated small fibers are not otherwise quantified objectively with such a level of sensitivity as has been reported with IENFD. Recent advances include an expansion of the skin punch biopsy technique to evaluate larger myelinated fibers and mechanoreceptors, and recent work has also focused on additional methods of quantifying dermal fibers and densely innervated autonomic structures. This review discusses current work using skin biopsy for the pathologic analysis of peripheral nerve fibers in neuropathy of various causes as well as its use in clinical trials. PMID:23250768

Myers, M. Iliza; Peltier, Amanda C.

2013-01-01

52

Does low-intensity helium-neon laser irradiation alter sensory nerve active potentials or distal latencies  

SciTech Connect

The effect of 1 mW helium neon continuous-wave (0.633 microns) laser irradiation on superficial radical sensory and median sensory nerve function was examined in a double-blind, controlled study involving 40 volunteers. No differences in action potential amplitudes, distal latencies, or forearm skin temperatures were found between the treated and control groups either at the time of irradiation or at subsequent evaluations 15 and 30 minutes later. As a result, we are unable to confirm reports that low-energy lasers of this power and wavelength alter nerve function.

Basford, J.R.; Daube, J.R.; Hallman, H.O.; Millard, T.L.; Moyer, S.K. (Mayo Clinic and Foundation, Rochester, MN (USA))

1990-01-01

53

The structure of the cereal sensory system and ventral nerve cord of Grylloblatta  

Microsoft Academic Search

The structure of cereal sensilla, the cereal nerve and the central projections of the cereal sensory nerve of a notopteran (Grylloblatta sp.) are described and compared with other orthopteroid insects in which the cereal sensory system and central connections are well known. The cereal sensilla are similar to those of gryllids and blattids, but the gross structure of the cerci

John S. Edwards; Daniel Mann

1981-01-01

54

Sensory nerves and nitric oxide contribute to reflex cutaneous vasodilation in humans.  

PubMed

We tested the hypothesis that inhibition of cutaneous sensory nerves would attenuate reflex cutaneous vasodilation in response to an increase in core temperature. Nine subjects were equipped with four microdialysis fibers on the forearm. Two sites were treated with topical anesthetic EMLA cream for 120 min. Sensory nerve inhibition was verified by lack of sensation to a pinprick. Microdialysis fibers were randomly assigned as 1) lactated Ringer (control); 2) 10 mM nitro-L-arginine methyl ester (L-NAME) to inhibit nitric oxide synthase; 3) EMLA + lactated Ringer; and 4) EMLA + L-NAME. Laser-Doppler flowmetry was used as an index of skin blood flow, and blood pressure was measured via brachial auscultation. Subjects wore a water-perfused suit, and oral temperature was monitored as an index of core temperature. The suit was perfused with 50°C water to initiate whole body heat stress to raise oral temperature 0.8°C above baseline. Cutaneous vascular conductance (CVC) was calculated and normalized to maximal vasodilation (%CVC(max)). There was no difference in CVC between control and EMLA sites (67 ± 5 vs. 69 ± 6% CVC(max)), but the onset of vasodilation was delayed at EMLA compared with control sites. The L-NAME site was significantly attenuated compared with control and EMLA sites (45 ± 5% CVC(max); P < 0.01). Combined EMLA + L-NAME site (25 ± 6% CVC(max)) was attenuated compared with control and EMLA (P < 0.001) and L-NAME only (P < 0.01). These data suggest cutaneous sensory nerves contribute to reflex cutaneous vasodilation during the early, but not latter, stages of heat stress, and full expression of reflex cutaneous vasodilation requires functional sensory nerves and NOS. PMID:23408029

Wong, Brett J

2013-04-15

55

Neonatal de-afferentation of capsaicin-sensitive sensory nerves increases in vivo insulin sensitivity in conscious adult rats  

Microsoft Academic Search

Summary   Sensory neuropeptides, released from the peripheral nervous system, might modulate glucose homeostasis by antagonizing insulin\\u000a action. The effects of de-afferentation of functional small diameter unmyelinated C-fibres (sensory nerves) on in vivo insulin-mediated\\u000a intracellular glucose metabolism were investigated by using euglycaemic insulin (6 and 18 mU\\/kg.min) clamps with [3-3H]-glucose infusion in 24 adult rats, treated neonatally with either capsaicin (CAP)

S. J. Koopmans; B. Leighton; R. A. DeFronzo

1998-01-01

56

Prior Collateral Sprouting of Sensory Axons Delays Recovery of Pain Sensitivity after Subsequent Nerve Crush  

Microsoft Academic Search

Regeneration of motor axons is enhanced if they have sprouted prior to nerve injury. We examined whether sensory axon regeneration and recovery of pain response was affected by previous collateral sprouting. In the experimental group of rats, the right saphenous, tibial, and sural nerves were transected and ligated. The peroneal nerve was left to sprout into the adjacent denervated skin.

Fajko Bajrovi?; Janez Sketelj

1996-01-01

57

Immunohistochemical localization of laminin and type IV collagen in human cutaneous sensory nerve formations  

Microsoft Academic Search

We used immunohistochemical techniques and monoclonal antibodies to localize two basement membrane components (laminin and type IV collagen) in the nerves and sensory nerve formations, or corpuscles, supplying human digital skin. Furthermore, neurofilament proteins, S-100 protein and epithelial membrane antigen were studied in parallel. In dermal nerve trunks, immunostaining for laminin and type IV collagen was found to be co-localized

J. A. Vega; I. Esteban; F. J. Naves; M. E. Valle; L. Malinovsky

1995-01-01

58

Photostimulation of sensory neurons of the rat vagus nerve  

NASA Astrophysics Data System (ADS)

We studied the effect of infrared (IR) stimulation on rat sensory neurons. Primary sensory neurons were prepared by enzymatic dissociation of the inferior (or "nodose") ganglia from the vagus nerves of rats. The 1.85-?m output of a diode laser, delivered through a 200-?m silica fiber, was used for photostimulation. Nodose neurons express the vanilloid receptor, TRPV1, which is a non-selective cation channel that opens in response to significant temperature jumps above 37 C. Opening TRPV1 channels allows entry of cations, including calcium (Ca 2+), into the cell to cause membrane depolarization. Therefore, to monitor TRPV1 activation consequent to photostimulation, we used fura-2, a fluorescent Ca 2+ indicator, to monitor the rise in intracellular Ca 2+ concentration ([Ca 2+]i). Brief trains of 2-msec IR pulses activated TRPV1 rapidly and reversibly, as evidenced by transient rises in [Ca 2+]i (referred to as Ca 2+ transients). Consistent with the Ca 2+ transients arising from influx of Ca 2+, identical photostimulation failed to evoke Ca 2+ responses in the absence of extracellular Ca 2+. Furthermore, the photo-induced Ca 2+ signals were abolished by capsazepine, a specific blocker of TRPV1, indicating that the responses were indeed mediated by TRPV1. We discuss the feasibility of using focal IR stimulation to probe neuronal circuit properties in intact neural tissue, and compare IR stimulation with another photostimulation technique-focal photolytic release of "caged" molecules.

Rhee, Albert Y.; Li, Gong; Wells, Jonathon; Kao, Joseph P. Y.

2008-02-01

59

Arnold’s nerve cough reflex: evidence for chronic cough as a sensory vagal neuropathy  

PubMed Central

Arnold’s nerve ear-cough reflex is recognised to occur uncommonly in patients with chronic cough. In these patients, mechanical stimulation of the external auditory meatus can activate the auricular branch of the vagus nerve (Arnold’s nerve) and evoke reflex cough. This is an example of hypersensitivity of vagal afferent nerves, and there is now an increasing recognition that many cases of refractory or idiopathic cough may be due to a sensory neuropathy of the vagus nerve. We present two cases where the cause of refractory chronic cough was due to sensory neuropathy associated with ear-cough reflex hypersensitivity. In both cases, the cough as well as the Arnold’s nerve reflex hypersensitivity were successfully treated with gabapentin, a treatment that has previously been shown to be effective in the treatment of cough due to sensory laryngeal neuropathy (SLN). PMID:25383210

Gibson, Peter G.; Birring, Surinder S.

2014-01-01

60

Arnold's nerve cough reflex: evidence for chronic cough as a sensory vagal neuropathy.  

PubMed

Arnold's nerve ear-cough reflex is recognised to occur uncommonly in patients with chronic cough. In these patients, mechanical stimulation of the external auditory meatus can activate the auricular branch of the vagus nerve (Arnold's nerve) and evoke reflex cough. This is an example of hypersensitivity of vagal afferent nerves, and there is now an increasing recognition that many cases of refractory or idiopathic cough may be due to a sensory neuropathy of the vagus nerve. We present two cases where the cause of refractory chronic cough was due to sensory neuropathy associated with ear-cough reflex hypersensitivity. In both cases, the cough as well as the Arnold's nerve reflex hypersensitivity were successfully treated with gabapentin, a treatment that has previously been shown to be effective in the treatment of cough due to sensory laryngeal neuropathy (SLN). PMID:25383210

Ryan, Nicole M; Gibson, Peter G; Birring, Surinder S

2014-10-01

61

Schwann Cells Seeded in Acellular Nerve Grafts Improve Functional Recovery  

PubMed Central

Introduction This study evaluated whether Schwann cells (SCs) from different nerve sources transplanted into cold-preserved acellular nerve grafts (CP-ANGs) would improve functional regeneration compared to nerve isografts. Methods SCs isolated and expanded from motor and sensory branches of rat femoral and sciatic nerves were seeded into 14mm CP-ANGs. Growth factor expression, axonal regeneration, and functional recovery were evaluated in a14 mm rat sciatic injury model and compared to isografts. Results At 14 days, motor or sensory-derived SCs increased expression of growth factors in CP-ANGs versus isografts. After 42 days, histomorphometric analysis found CP-ANGs with SCs and isografts had similar numbers of regenerating nerve fibers. At 84 days, muscle force generation was similar for CP-ANGs with SCs and isografts. SC source did not affect nerve fiber counts or muscle force generation. Discussion SCs transplanted into CP-ANGs increase functional regeneration to isograft levels; however SC nerve source did not have an effect. PMID:23625513

Jesuraj, Nithya J.; Santosa, Katherine B.; MacEwan, Matthew R.; Moore, Amy M.; Kasukurthi, Rahul; Ray, Wilson Z.; Flagg, Eric R.; Hunter, Daniel A.; Borschel, Gregory H.; Johnson, Philip J.; Mackinnon, Susan E.; Sakiyama-Elbert, Shelly E.

2014-01-01

62

Immunohistochemistry of displaced sensory neurons in the trigeminal nerve root.  

PubMed

The aim of this study was to examine the morphology and the immunohistochemical features of displaced ganglion cells in the trigeminal nerve root (TNR). Forty human TNRs of 20 persons, obtained during routine autopsy in accordance with the Declaration of Helsinki, were examined following Klüver-Barrera and azan trichrome histological staining, and immunohistochemical reactions against certain neuronal markers, neuropeptides and neurotransmitters. A total number of 61 displaced neurons were investigated, which were present in 80% of individuals studied. Displaced neurons were found in 55.0% of the TNRs, either in the sensory portion (22.5%), motor portion (22.5%) or both (10.0%). Neuronal diameter varied from 12.5 x 25.0 to 45.0 x 63.7 (mean 27.6 x 41.6) microm, and in area between 245 and 2,065 (mean 927) microm(2). Each neuron was surrounded by 2-17 elongated satellite cells per slice. The immune reaction was positive in all the neurons studied for neuron-specific enolase, protein gene product 9.5, neurofilament protein and synaptophysin, and in some neurons for calcitonin gene-related peptide (CGRP; 24.4%), cholecystokinin (CCK; 13.3%), somatostatin (SST; 17.8%), substance P (SP; 15.6%), vasoactive intestinal polypeptide (4.4%), neuropeptide Y (8.9%), and serotonin (11.1%). The immune reactions were most frequent against the CGRP, SP, CCK and SST. We concluded that displaced neurons in the TNR morphologically and immunohistochemically resembled the sensory neurons in the trigeminal ganglion. PMID:19923783

Marinkovi?, Slobodan; Cetkovi?, Mila; Gibo, Hirohiko; Todorovi?, Vera; Janci?, Jasna; Milisavljevi?, Milan

2010-01-01

63

Etifoxine improves peripheral nerve regeneration and functional recovery  

PubMed Central

Peripheral nerves show spontaneous regenerative responses, but recovery after injury or peripheral neuropathies (toxic, diabetic, or chronic inflammatory demyelinating polyneuropathy syndromes) is slow and often incomplete, and at present no efficient treatment is available. Using well-defined peripheral nerve lesion paradigms, we assessed the therapeutic usefulness of etifoxine, recently identified as a ligand of the translocator protein (18 kDa) (TSPO), to promote axonal regeneration, modulate inflammatory responses, and improve functional recovery. We found by histologic analysis that etifoxine therapy promoted the regeneration of axons in and downstream of the lesion after freeze injury and increased axonal growth into a silicone guide tube by a factor of 2 after nerve transection. Etifoxine also stimulated neurite outgrowth in PC12 cells, and the effect was even stronger than for specific TSPO ligands. Etifoxine treatment caused a marked reduction in the number of macrophages after cryolesion within the nerve stumps, which was rapid in the proximal and delayed in the distal nerve stumps. Functional tests revealed accelerated and improved recovery of locomotion, motor coordination, and sensory functions in response to etifoxine. This work demonstrates that etifoxine, a clinically approved drug already used for the treatment of anxiety disorders, is remarkably efficient in promoting acceleration of peripheral nerve regeneration and functional recovery. Its possible mechanism of action is discussed, with reference to the neurosteroid concept. This molecule, which easily enters nerve tissues and regulates multiple functions in a concerted manner, offers promise for the treatment of peripheral nerve injuries and axonal neuropathies. PMID:19075249

Girard, Christelle; Liu, Song; Cadepond, Françoise; Adams, David; Lacroix, Catherine; Verleye, Marc; Gillardin, Jean-Marie; Baulieu, Etienne-Emile; Schumacher, Michael; Schweizer-Groyer, Ghislaine

2008-01-01

64

Etifoxine improves peripheral nerve regeneration and functional recovery.  

PubMed

Peripheral nerves show spontaneous regenerative responses, but recovery after injury or peripheral neuropathies (toxic, diabetic, or chronic inflammatory demyelinating polyneuropathy syndromes) is slow and often incomplete, and at present no efficient treatment is available. Using well-defined peripheral nerve lesion paradigms, we assessed the therapeutic usefulness of etifoxine, recently identified as a ligand of the translocator protein (18 kDa) (TSPO), to promote axonal regeneration, modulate inflammatory responses, and improve functional recovery. We found by histologic analysis that etifoxine therapy promoted the regeneration of axons in and downstream of the lesion after freeze injury and increased axonal growth into a silicone guide tube by a factor of 2 after nerve transection. Etifoxine also stimulated neurite outgrowth in PC12 cells, and the effect was even stronger than for specific TSPO ligands. Etifoxine treatment caused a marked reduction in the number of macrophages after cryolesion within the nerve stumps, which was rapid in the proximal and delayed in the distal nerve stumps. Functional tests revealed accelerated and improved recovery of locomotion, motor coordination, and sensory functions in response to etifoxine. This work demonstrates that etifoxine, a clinically approved drug already used for the treatment of anxiety disorders, is remarkably efficient in promoting acceleration of peripheral nerve regeneration and functional recovery. Its possible mechanism of action is discussed, with reference to the neurosteroid concept. This molecule, which easily enters nerve tissues and regulates multiple functions in a concerted manner, offers promise for the treatment of peripheral nerve injuries and axonal neuropathies. PMID:19075249

Girard, Christelle; Liu, Song; Cadepond, Françoise; Adams, David; Lacroix, Catherine; Verleye, Marc; Gillardin, Jean-Marie; Baulieu, Etienne-Emile; Schumacher, Michael; Schweizer-Groyer, Ghislaine

2008-12-23

65

Changes in sensory activity of ocular surface sensory nerves during allergic keratoconjunctivitis.  

PubMed

Peripheral neural mechanisms underlying the sensations of irritation, discomfort, and itch accompanying the eye allergic response have not been hitherto analyzed. We explored this question recording the changes in the electrical activity of corneoconjunctival sensory nerve fibers of the guinea pig after an ocular allergic challenge. Sensitization was produced by i.p. ovalbumin followed by repeated application in the eye of 10% ovalbumin on days 14 to 18. Blinking and tearing rate were measured. Spontaneous and stimulus-evoked (mechanical, thermal, chemical) impulse activity was recorded from mechanonociceptor, polymodal nociceptor and cold corneoscleral sensory afferent fibers. After a single (day 14) or repeated daily exposures to the allergen during the following 3 to 4days, tearing and blinking rate increased significantly. Also, sensitization was observed in mechanonociceptors (transient reduction of mechanical threshold only on day 14) and in polymodal nociceptors (sustained enhancement of the impulse response to acidic stimulation). In contrast, cold thermoreceptors showed a significant decrease in basal ongoing activity and in the response to cooling. Treatment with the TRPV1 and TRPA1 blockers capsazepine and HC-030031 reversed the augmented blinking. Only capsazepine attenuated tearing rate increase and sensitization of the polymodal nociceptors response to CO2. Capsazepine also prevented the decrease in cold thermoreceptor activity caused by the allergic challenge. We conclude that changes in nerve impulse activity accompanying the ocular allergic response, primarily mediated by activation of nociceptor's TRPV1 and to a lesser degree by activation of TRPA1 channels, explain the eye discomfort sensations accompanying allergic episodes. PMID:23867735

Acosta, M Carmen; Luna, Carolina; Quirce, Susana; Belmonte, Carlos; Gallar, Juana

2013-11-01

66

Selective Targeting of TRPV1 Expressing Sensory Nerve Terminals in the Spinal Cord for Long Lasting Analgesia  

PubMed Central

Chronic pain is a major clinical problem and opiates are often the only treatment, but they cause significant problems ranging from sedation to deadly respiratory depression. Resiniferatoxin (RTX), a potent agonist of Transient Receptor Potential Vanilloid 1 (TRPV1), causes a slow, sustained and irreversible activation of TRPV1 and increases the frequency of spontaneous excitatory postsynaptic currents, but causes significant depression of evoked EPSCs due to nerve terminal depolarization block. Intrathecal administration of RTX to rats in the short-term inhibits nociceptive synaptic transmission, and in the long-term causes a localized, selective ablation of TRPV1-expressing central sensory nerve terminals leading to long lasting analgesia in behavioral models. Since RTX actions are selective for central sensory nerve terminals, other efferent functions of dorsal root ganglion neurons can be preserved. Preventing nociceptive transmission at the level of the spinal cord can be a useful strategy to treat chronic, debilitating and intractable pain. PMID:19753113

Sikand, Parul; Parihar, Arti; Evans, M. Steven; Premkumar, Louis S.

2009-01-01

67

Early evaluation of nerve regeneration after nerve injury and repair using functional connectivity MRI.  

PubMed

Resting state functional connectivity magnetic resonance imaging studies in rat brain show brain reorganization caused by nerve injury and repair. In this study, distinguishable differences were found in healthy, nerve transection without repair (R-) and nerve transection with repair (R+) groups in the subacute stage (2 weeks after initial injury). Only forepaw on the healthy side was used to determine seed voxel regions in this study. Disturbance of neuronal network in the primary sensory region of cortex occurs within two hours after initial injury, and the network pattern was restored in R+ group in subacute stage, while the disturbed pattern remained in R- group. These are the central findings of the study. This technique provides a novel way of detecting and monitoring the effectiveness of peripheral nerve injury treatment in the early stage and potentially offers a tool for clinicians to avoid poor clinical outcomes. PMID:24515926

Li, Rupeng; Hettinger, Patrick C; Liu, Xiping; Machol, Jacques; Yan, Ji-Geng; Matloub, Hani S; Hyde, James S

2014-09-01

68

Development and neuronal dependence of cutaneous sensory nerve formations: Lessons from neurotrophins.  

PubMed

Null mutations of genes from the NGF family of NTs and their receptors (NTRs) lead to loss/reduction of specific neurons in sensory ganglia; conversely, cutaneous overexpression of NTs results in skin hyperinnervation and increase or no changes in the number of sensory neurons innervating the skin. These neuronal changes are paralleled with loss of specific types of sensory nerve formations in the skin. Therefore, mice carrying mutations in NT or NTR genes represent an ideal model to identify the neuronal dependence of each type of cutaneous sensory nerve ending from a concrete subtype of sensory neuron, since the development, maintenance, and structural integrity of sensory nerve formations depend upon sensory neurons. Results obtained from these mouse strains suggest that TrkA positive neurons are connected to intraepithelial nerve fibers and other sensory nerve formations depending from C and Adelta nerve fibers; the neurons expressing TrkB and responding to BDNF and NT-4 innervate Meissner corpuscles, a subpopulation of Merkell cells, some mechanoreceptors of the piloneural complex, and the Ruffini's corpuscles; finally, a subpopulation of neurons, which are responsive to NT-3, support postnatal survival of some intraepithelial nerve fibers and Merkel cells in addition to the muscle mechanoreceptors. On the other hand, changes in NTs and NTRs affect the structure of non-nervous structures of the skin and are at the basis of several cutaneous pathologies. This review is an update about the role of NTs and NTRs in the maintenance of normal cutaneous innervation and maintenance of skin integrity. PMID:19839059

Montańo, Juan A; Pérez-Pińera, Pablo; García-Suárez, Olivia; Cobo, Juan; Vega, Jose A

2010-05-01

69

Artemin induced functional recovery and reinnervation after partial nerve injury.  

PubMed

Systemic artemin promotes regeneration of dorsal roots to the spinal cord after crush injury. However, it is unclear whether systemic artemin can also promote peripheral nerve regeneration, and functional recovery after partial lesions distal to the dorsal root ganglion (DRG) remains unknown. In the present investigation, male Sprague Dawley rats received axotomy, ligation, or crush of the L5 spinal nerve or sham surgery. Starting the day of injury, animals received intermittent subcutaneous artemin or vehicle across 2weeks. Sensory thresholds to tactile or thermal stimuli were monitored for 6weeks after injury. Immunohistochemical analyses of the DRG and nerve regeneration were performed at the 6-week time point. Artemin transiently reversed tactile and thermal hypersensitivity after axotomy, ligation, or crush injury. Thermal and tactile hypersensitivity reemerged within 1week of treatment termination. However, artemin-treated rats with nerve crush, but not axotomy or ligation, subsequently showed gradual return of sensory thresholds to preinjury baseline levels by 6weeks after injury. Artemin normalized labeling for NF200, IB4, and CGRP in nerve fibers distal to the crush injury, suggesting persistent normalization of nerve crush-induced neurochemical changes. Sciatic and intradermal administration of dextran or cholera toxin B distal to the crush injury site resulted in labeling of neuronal profiles in the L5 DRG, suggesting regeneration functional restoration of nonmyelinated and myelinated fibers across the injury site into cutaneous tissue. Artemin also diminished ATF3 and caspase 3 expression in the L5 DRG, suggesting persistent neuroprotective actions. A limited period of artemin treatment elicits disease modification by promoting sensory reinnervation of distal territories and restoring preinjury sensory thresholds. PMID:24269493

Wang, Ruizhong; Rossomando, Anthony; Sah, Dinah W Y; Ossipov, Michael H; King, Tamara; Porreca, Frank

2014-03-01

70

Myelinated sensory and alpha motor axon regeneration in peripheral nerve neuromas  

NASA Technical Reports Server (NTRS)

Histochemical staining for carbonic anhydrase and cholinesterase (CE) activities was used to analyze sensory and motor axon regeneration, respectively, during neuroma formation in transected and tube-encapsulated peripheral nerves. Median-ulnar and sciatic nerves in the rodent model permitted testing whether a 4 cm greater distance of the motor neuron soma from axotomy site or intrinsic differences between motor and sensory neurons influenced regeneration and neuroma formation 10, 30, and 90 days later. Ventral root radiculotomy confirmed that CE-stained axons were 97% alpha motor axons. Distance significantly delayed axon regeneration. When distance was negligible, sensory axons grew out sooner than motor axons, but motor axons regenerated to a greater quantity. These results indicate regeneration differences between axon subtypes and suggest more extensive branching of motor axons within the neuroma. Thus, both distance from injury site to soma and inherent motor and sensory differences should be considered in peripheral nerve repair strategies.

Macias, M. Y.; Lehman, C. T.; Sanger, J. R.; Riley, D. A.

1998-01-01

71

BREAST CANCER-INDUCED BONE REMODELING, SKELETAL PAIN AND SPROUTING OF SENSORY NERVE FIBERS  

PubMed Central

Breast cancer metastasis to bone is frequently accompanied by pain. What remains unclear is why this pain tends to become more severe and difficult to control with disease progression. Here we test the hypothesis that with disease progression sensory nerve fibers that innervate the breast cancer bearing bone undergo a pathological sprouting and reorganization, which in other non-malignant pathologies has been shown to generate and maintain chronic pain. Injection of human breast cancer cells (MDA-MB-231-BO) into the femoral intramedullary space of female athymic nude mice induces sprouting of calcitonin gene-related peptide (CGRP+) sensory nerve fibers. Nearly all CGRP+ nerve fibers that undergo sprouting also co-express tropomyosin receptor kinase A (TrkA+) and growth associated protein-43 (GAP43+). This ectopic sprouting occurs in periosteal sensory nerve fibers that are in close proximity to breast cancer cells, tumor-associated stromal cells and remodeled cortical bone. Therapeutic treatment with an antibody that sequesters nerve growth factor (NGF), administered when the pain and bone remodeling were first observed, blocks this ectopic sprouting and attenuates cancer pain. The present data suggest that the breast cancer cells and tumor-associated stromal cells express and release NGF, which drives bone pain and the pathological reorganization of nearby CGRP+ / TrkA+ / GAP43+ sensory nerve fibers. PMID:21497141

Bloom, Aaron P.; Jimenez-Andrade, Juan M.; Taylor, Reid N.; Castańeda-Corral, Gabriela; Kaczmarska, Magdalena J.; Freeman, Katie T.; Coughlin, Kathleen A.; Ghilardi, Joseph R.; Kuskowski, Michael A.; Mantyh, Patrick W.

2011-01-01

72

Functional and topographic segregation of glomeruli revealed by local staining of antennal sensory neurons in the honeybee Apis mellifera.  

PubMed

In the primary olfactory center of animals, glomeruli are the relay stations where sensory neurons expressing cognate odorant receptors converge onto interneurons. In cockroaches, moths, and honeybees, sensory afferents from sensilla on the anterodorsal surface and the posteroventral surface of the flagellum form two nerves of almost equal thicknesses. In this study, double labeling of the two nerves, or proximal/distal regions of the nerves, with fluorescent dyes was used to investigate topographic organization of sensory afferents in the honeybee. The sensory neurons of ampullaceal sensilla responsive to CO2, coelocapitular sensilla responsive to hygrosensory, and thermosensory stimuli and coeloconic sensilla of unknown function were characterized with large somata and supplied thick axons exclusively to the ventral nerve. Correspondingly, all glomeruli innervated by sensory tract (T) 4 received thick axonal processes exclusively from the ventral nerve. Almost all T1-3 glomeruli received a similar number of sensory afferents from the two nerves. In the macroglomerular complexes of the drone, termination fields of afferents from the two nerves almost completely overlapped; this differs from moths and cockroaches, which show heterogeneous terminations in the glomerular complex. In T1-3 glomeruli, sensory neurons originating from more distal flagellar segments tended to terminate within the inner regions of the cortical layer. These results suggest that some degree of somatotopic organization of sensory afferents exist in T1-3 glomeruli, and part of T4 glomeruli serve for processing of hygro- and thermosensory signals. PMID:19412930

Nishino, Hiroshi; Nishikawa, Michiko; Mizunami, Makoto; Yokohari, Fumio

2009-07-10

73

Effect of pulsed infrared lasers on neural conduction and axoplasmic transport in sensory nerves  

NASA Astrophysics Data System (ADS)

Over the past ten years there has been an increasing interest in the use of lasers for neurosurgical and neurological procedures. Novel recent applications range from neurosurgical procedures such as dorsal root entry zone lesions made with argon and carbon dioxide microsurgical lasers to pain relief by low power laser irradiation of the appropriate painful nerve or affected region1 '2 However, despite the widespread clinical applications of laser light, very little is known about the photobiological interactions between laser light and nervous tissue. The present studies were designed to evaluate the effects of pulsed Nd:YAG laser light on neural impulse conduction and axoplasmic transport in sensory nerves in rats and cats. Our data indicate that Q-switched Nd:YAG laser irradiation can induce a preferential impairment of (1) the synaptic effects of small afferent fibers on dorsal horn cells in the spinal cord and of (2) small slow conducting sensory nerve fibers in dorsal roots and peripheral nerves. These results imply that laser light might have selective effects on impulse conduction in slow conducting sensory nerve fibers. In agreement with our elecirophysiological observations recent histological data from our laboratory show, that axonal transport of the enzyme horseradish peroxidase is selectively impaired in small sensory nerve fibers. In summary these data indicate, that Q-switched Nd:YAG laser irradiation can selectively impair neural conduction and axoplasmic transport in small sensory nerve fibers as compared to fast conducting fibers. A selective influence of laser irradiation on slow conducting fibers could have important clinical applications, especially for the treatment of chronic pain.

Wesselmann, Ursula; Rymer, William Z.; Lin, Shien-Fong

1990-06-01

74

Effect of helium-neon laser irradiation on peripheral sensory nerve latency  

SciTech Connect

The purpose of this randomized, double-blind study was to determine the effect of a helium-neon (He-Ne) laser on latency of peripheral sensory nerve. Forty healthy subjects with no history of right upper extremity pathological conditions were assigned to either a Laser or a Placebo Group. Six 1-cm2 blocks along a 12-cm segment of the subjects' right superficial radial nerve received 20-second applications of either the He-Ne laser or a placebo. We assessed differences between pretest and posttest latencies with t tests for correlated and independent samples. The Laser Group showed a statistically significant increase in latency that corresponded to a decrease in sensory nerve conduction velocity. Short-duration He-Ne laser application significantly increased the distal latency of the superficial radial nerve. This finding provides information about the mechanism of the reported pain-relieving effect of the He-Ne laser.

Snyder-Mackler, L.; Bork, C.E.

1988-02-01

75

Nitric oxide nerves in the uterus are parasympathetic, sensory, and contain neuropeptides  

Microsoft Academic Search

Nitric oxide (NO) is synthesized in neurons and is a potent relaxor of vascular and nonvascular smooth muscle. The uterus contains abundant NO-synthesizing nerves which could be autonomic and\\/or sensory. This study was undertaken to determine: 1) the source(s) of NO-synthesizing nerves in the rat uterus and 2) what other neuropeptides or transmitter markers might coexist with NO in these

Raymond E. Papka; Daniel L. McNeill; Donna Thompson; Harald H. H. W. Schmidt

1995-01-01

76

Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats  

SciTech Connect

Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a promising strategy for peripheral nerve repair.

Cheng, Lei; Liu, Yi; Zhao, Hua; Zhang, Wen; Guo, Ying-Jun; Nie, Lin, E-mail: chengleiyx@126.com

2013-10-18

77

Systemic acetyl- l -carnitine eliminates sensory neuronal loss after peripheral axotomy: a new clinical approach in the management of peripheral nerve trauma  

Microsoft Academic Search

Several hundred thousand peripheral nerve injuries occur each year in Europe alone. Largely due to the death of around 40%\\u000a of primary sensory neurons, sensory outcome remains disappointingly poor despite considerable advances in surgical technique;\\u000a yet no clinical therapies currently exist to prevent this neuronal death. Acetyl-l-carnitine (ALCAR) is a physiological peptide with roles in mitochondrial bioenergetic function, which may

Andrew McKay Hart; Mikael Wiberg; Mike Youle; Giorgio Terenghi

2002-01-01

78

Electromyographic mixed nerve and cutaneous silent period in evaluating the A-delta fibres in a patient with hereditary sensory-autonomic neuropathy.  

PubMed

The aim of this study was to evaluate A-delta fibre function in a patient with hereditary sensory-autonomic neuropathy (HSAN). We used the mixed and cutaneous silent period techniques in addition to a conventional electromyographic investigation in a patient with type 2 HSAN, a rare disease characterised by wide-spread sensory and variable autonomic dysfunction caused by incomplete development of sensory and autonomic neurons. Whereas the stimulation of one digital nerve did not show any evidence of silent period in either the left or the right hand, the simultaneous stimulation of two digital nerves, as well as the stimulation of a mixed nerve, revealed a measurable delayed and shortened silent period. These data suggest that a spatial summation mediated by A-delta fibres was required for generation of the silent period in this patient and that combining the CSP and MNSP may be of practical use in evaluating impairment of the small myelinated fibres. PMID:12086110

Corsi, Fablo Maria; Fausti, Silvia; Serrao, Mariano; Casali, Carlo; Parisi, Leoluca; Piazza, Giuseppe

2002-01-01

79

Sensory nerve conduction in branches of common interdigital nerves: a new technique for normal controls and patients with morton's neuroma.  

PubMed

In this article, a new electrodiagnostic approach is described for patients with Morton's neuroma. The new method is based on the anatomic fact that the two branches of the common plantar interdigital nerves innervate the lateral side of one toe and the medial side the next one. This study included 20 normal subjects (aged 28-58 years, 10 men and 10 women) and 4 patients with Morton's neuroma (aged 44-52 years, 4 women). The branches of adjacent common plantar interdigital nerves that innerve one toe were stimulated superficially and separately with half of one toe covered with a piece of medical tape. The recordings were obtained on the posterior tibial nerve at the medial malleolus with needle electrodes. Thus, the difference in latencies of obtained sensory nerve action potentials on the posterior tibial nerve with needle electrode was measured. From normal subjects' data, it was determined that a latency difference value of above 0.17 milliseconds (mean +/- 2.5 SD) in one toe was abnormal. All of the patients with Morton's neuroma showed abnormal interlatency difference values. This new method, which we have developed, is more sensitive, simple to use, does not require extra equipment, and does not cause excessive pain. We suggest that interlatency difference between branches of the common plantar interdigital nerves is a useful and sensitive method for the diagnosis of Morton's neuroma. PMID:20479659

Uludag, Burhanettin; Tataroglu, Cengiz; Bademkiran, Fikret; Uludag, Irem Fatma; Ertekin, Cumhur

2010-06-01

80

Sensory signs in complex regional pain syndrome and peripheral nerve injury.  

PubMed

This study determined patterns of sensory signs in complex regional pain syndrome (CRPS) type I and II and peripheral nerve injury (PNI). Patients with upper-limb CRPS-I (n=298), CRPS-II (n=46), and PNI (n=72) were examined with quantitative sensory testing according to the protocol of the German Research Network on Neuropathic Pain. The majority of patients (66%-69%) exhibited a combination of sensory loss and gain. Patients with CRPS-I had more sensory gain (heat and pressure pain) and less sensory loss than patients with PNI (thermal and mechanical detection, hypoalgesia to heat or pinprick). CRPS-II patients shared features of CRPS-I and PNI. CRPS-I and CRPS-II had almost identical somatosensory profiles, with the exception of a stronger loss of mechanical detection in CRPS-II. In CRPS-I and -II, cold hyperalgesia/allodynia (28%-31%) and dynamic mechanical allodynia (24%-28%) were less frequent than heat or pressure hyperalgesia (36%-44%, 67%-73%), and mechanical hypoesthesia (31%-55%) was more frequent than thermal hypoesthesia (30%-44%). About 82% of PNI patients had at least one type of sensory gain. QST demonstrates more sensory loss in CRPS-I than hitherto considered, suggesting either minimal nerve injury or central inhibition. Sensory profiles suggest that CRPS-I and CRPS-II may represent one disease continuum. However, in contrast to recent suggestions, small fiber deficits were less frequent than large fiber deficits. Sensory gain is highly prevalent in PNI, indicating a better similarity of animal models to human patients than previously thought. These sensory profiles should help prioritize approaches for translation between animal and human research. PMID:22154921

Gierthmühlen, Janne; Maier, Christoph; Baron, Ralf; Tölle, Thomas; Treede, Rolf-Detlef; Birbaumer, Niels; Huge, Volker; Koroschetz, Jana; Krumova, Elena K; Lauchart, Meike; Maihöfner, Christian; Richter, Helmut; Westermann, Andrea

2012-04-01

81

Mustard oils and cannabinoids excite sensory nerve fibres through the TRP channel ANKTM1  

Microsoft Academic Search

Wasabi, horseradish and mustard owe their pungency to isothiocyanate compounds. Topical application of mustard oil (allyl isothiocyanate) to the skin activates underlying sensory nerve endings, thereby producing pain, inflammation and robust hypersensitivity to thermal and mechanical stimuli. Despite their widespread use in both the kitchen and the laboratory, the molecular mechanism through which isothiocyanates mediate their effects remains unknown. Here

Sven-Eric Jordt; Diana M. Bautista; Huai-hu Chuang; David D. McKemy; Peter M. Zygmunt; Edward D. Högestätt; Ian D. Meng; David Julius

2004-01-01

82

Early social isolation provokes electrophysiological and structural changes in cutaneous sensory nerves of adult male rats.  

PubMed

Sensory and social deprivation from the mother and littermates during early life disturbs the development of the central nervous system, but little is known about its effect on the development of the peripheral nervous system. To assess peripheral effects of early isolation, male rat pups were reared artificially in complete social isolation (AR); reared artificially with two same-age conspecifics (AR-Social); or reared by their mothers and with littermates (MR). As adults, the electrophysiological properties of the sensory sural (SU) nerve were recorded. We found that the amplitude and normalized area (with respect to body weight) of the compound action potential (CAP) response provoked by single electrical pulses of graded intensity in the SU nerves of AR animals were shorter than the CAP recorded in SU nerves from MR and AR-Social animals. The slope of the stimulus-response curve of AR SU nerves was smaller than that of the other nerves. The histological characterization of axons in the SU nerves was made and showed that the myelin thickness of axons in AR SU nerves was significant lower (2-7µm) than that of the axons in the other nerves. Furthermore, the area and axon diameter of SU nerves of both AR and AR-Social animals were significant lower than in MR animals. This is the first report to show that maternal and littermate deprivation by AR disturbs the development of the myelination and electrophysiological properties of axons in the SU nerve; the replacement of social cues prevents most of the effects. PMID:24897933

Segura, Bertha; Melo, Angel I; Fleming, Alison S; Mendoza-Garrido, Maria Eugenia; González del Pliego, Margarita; Aguirre-Benitez, Elsa L; Hernández-Falcón, Jesús; Jiménez-Estrada, Ismael

2014-12-01

83

Variation in quantitative sensory testing and epidermal nerve fiber density in repeated measurements.  

PubMed

Quantitative sensory testing (QST) is commonly used to evaluate peripheral sensory function in neuropathic conditions. QST measures vary in repeated measurements of normal subjects but it is not known whether QST can reflect small changes in epidermal nerve fiber density (ENFd). This study evaluated QST measures (touch, mechanical pain, heat pain and innocuous cold sensations) for differences between genders and over time using ENFd as an objective-independent measure. QST was performed on the thighs of 36 healthy volunteers on four occasions between December and May. ENFd in skin biopsies was determined on three of those visits. Compared to men, women had a higher ENFd, a difference of 12.2 ENFs/mm. They also had lower tactile and innocuous cold thresholds, and detected mechanical pain (pinprick) at a higher frequency. Heat pain thresholds did not differ between genders. By the end of the 24-week study, men and women showed a small reduction (p<0.05) in the frequency of sharp mechanical pain evoked by pinprick whereas tactile and thermal thresholds showed no change. This coincided with a small decrease in ENFd, 4.18 ENFs/mm. Variation in measurements over time was large in a fraction of normal subjects. We conclude that most QST measures detect relatively large differences in epidermal innervation (12.2 ENFs/mm), but response to mechanical pain was the only sensory modality tested with the sensitivity to detect small changes in innervation (4.18 ENFs/mm). Since some individuals had large unsystematic variations, unexpected test results should therefore alert clinicians to test additional locations. PMID:20851518

Selim, Mona M; Wendelschafer-Crabb, Gwen; Hodges, James S; Simone, Donald A; Foster, Shawn X Y-L; Vanhove, Geertrui F; Kennedy, William R

2010-12-01

84

Patterned sensory nerve stimulation enhances the reactivity of spinal Ia inhibitory interneurons.  

PubMed

Patterned sensory nerve stimulation has been shown to induce plastic changes in the reciprocal Ia inhibitory circuit. However, the mechanisms underlying these changes have not yet been elucidated in detail. The aim of the present study was to determine whether the reactivity of Ia inhibitory interneurons could be altered by patterned sensory nerve stimulation. The degree of reciprocal Ia inhibition, the conditioning effects of transcranial magnetic stimulation (TMS) on the soleus (SOL) muscle H-reflex, and the ratio of the maximum H-reflex amplitude versus maximum M-wave (Hmax/Mmax) were examined in 10 healthy individuals. Patterned electrical nerve stimulation was applied to the common peroneal nerve every 1?s (100?Hz-5 train) at the motor threshold intensity of tibialis anterior muscle to induce activity changes in the reciprocal Ia inhibitory circuit. Reciprocal Ia inhibition, the TMS-conditioned H-reflex amplitude, and Hmax/Mmax were recorded before, immediately after, and 15?min after the electrical stimulation. The patterned electrical nerve stimulation significantly increased the degree of reciprocal Ia inhibition and decreased the amplitude of the TMS-conditioned H-reflex in the short-latency inhibition phase, which was presumably mediated by Ia inhibitory interneurons. However, it had no effect on Hmax/Mmax. Our results indicated that patterned sensory nerve stimulation could modulate the activity of Ia inhibitory interneurons, and this change may have been caused by the synaptic modification of Ia inhibitory interneuron terminals. These results may lead to a clearer understanding of the spinal cord synaptic plasticity produced by repetitive sensory inputs. PMID:25719751

Kubota, Shinji; Hirano, Masato; Morishita, Takuya; Uehara, Kazumasa; Funase, Kozo

2015-03-25

85

Anatomical coupling of sensory and motor nerve trajectory via axon tracking.  

PubMed

It is a long-standing question how developing motor and sensory neuron projections cooperatively form a common principal grid of peripheral nerve pathways relaying behavioral outputs and somatosensory inputs. Here, we explored this issue through targeted cell lineage and gene manipulation in mouse, combined with in vitro live axon imaging. In the absence of motor projections, dorsal (epaxial) and ventral (hypaxial) sensory projections form in a randomized manner, while removal of EphA3/4 receptor tyrosine kinases expressed by epaxial motor axons triggers selective failure to form epaxial sensory projections. EphA3/4 act non-cell-autonomously by inducing sensory axons to track along preformed epaxial motor projections. This involves cognate ephrin-A proteins on sensory axons but is independent from EphA3/4 signaling in motor axons proper. Assembly of peripheral nerve pathways thus involves motor axon subtype-specific signals that couple sensory projections to discrete motor pathways. PMID:21791286

Wang, Liang; Klein, Rüdiger; Zheng, Binhai; Marquardt, Till

2011-07-28

86

Autoradiographic location of sensory nerve endings in dentin of monkey teeth  

SciTech Connect

We have used the autoradiographic method to locate trigeminal nerve endings in monkey teeth. The nerve endings were labeled in two adult female Macaca fascicularis by 20 hours of axonal transport of radioactive protein (/sup 3/H-L-proline). We found a few labeled axons in contralateral mandibular central incisors and one mandibular canine. In ipsilateral teeth, numerous myelinated and unmyelinated axons were labeled; they formed a few terminal branches in the roots but primarily branched in the crown to form the peripheral plexus of Raschkow and to terminate as free endings in the odontoblast layer, predentin, and as far as 120 micrometers into dentinal tubules. Electron microscopic autoradiography showed that the radioactive axonally transported protein was confined to sensory axons and endings; odontoblasts and dentin matrix were not significantly labeled. Labeled free nerve endings were closely apposed to odontoblasts in dentin but did not form distinctive junctions with them. Nerve endings were most numerous in the regular tubular dentin of the crown adjacent to the tip of the pulp horn, occurring in at least half of the dentinal tubules there. Our results show tha dentinal sensory nerve endings in primate teeth can be profuse, sparse, or absent depending on the location and structure of dentin and its adjacent pulp. When dentin was innervated, the tubules were straight and contained odontoblast processes, the predentin was wide, the odontoblast cell bodies were relatively columnar, and there was an adjacent cell-free zone and pulpal nerve plexus.

Byers, M.R.; Dong, W.K.

1983-04-01

87

Nerve Conduction Studies of Median Motor Nerve and Median Sensory Branches According to the Severity of Carpal Tunnel Syndrome  

PubMed Central

Objective To evaluate each digital branch of the median sensory nerve and motor nerves to abductor pollicis brevis (APB) and 2nd lumbrical (2L) according to the severity of carpal tunnel syndrome (CTS). Methods A prospective study was performed in 67 hands of 41 patients with CTS consisting of mild, 23; moderate, 27; and severe cases, 17. Compound muscle action potentials (CMAPs) were obtained from APB and 2L, and median sensory nerve action potentials (SNAPs) were recorded from the thumb to the 4th digit. Parameters analyzed were latency of the median CMAP, latency difference of 2L and first palmar interosseous (PI), as well as latency and baseline to peak amplitude of the median SNAPs. Results The onset and peak latencies of the median SNAPs revealed significant differences only in the 2nd digit, according to the severity of CTS, and abnormal rates of the latencies were significantly lower in the 2nd digit to a mild degree. The amplitude of SNAP and sensory nerve conduction velocities were more preserved in the 2nd digit in mild CTS and more affected in the 4th digit in severe CTS. CMAPs were not evoked with APB recording in 4 patients with severe CTS, but obtained in all patients with 2L recording. 2L-PI showed statistical significance according to the severity of CTS. Conclusion The branch to the 4th digit was mostly involved and the branch to the 2nd digit and 2L were less affected in the progress of CTS. The second digit recorded SNAPs and 2L recorded CMAPs would be valuable in the evaluation of severe CTS. PMID:23705122

Lee, Hye Jin; Kim, Dong Hwee; Pyun, Sung Bom

2013-01-01

88

Refining the Sensory and Motor Ratunculus of the Rat Upper Extremity Using fMRI and Direct Nerve Stimulation  

PubMed Central

It is well understood that the different regions of the body have cortical representations in proportion to the degree of innervation. Our current understanding of the rat upper extremity has been enhanced using functional MRI (fMRI), but these studies are often limited to the rat forepaw. The purpose of this study is to describe a new technique that allows us to refine the sensory and motor representations in the cerebral cortex by surgically implanting electrodes on the major nerves of the rat upper extremity and providing direct electrical nerve stimulation while acquiring fMRI images. This technique was used to stimulate the ulnar, median, radial, and musculocutaneous nerves in the rat upper extremity using four different stimulation sequences that varied in frequency (5 Hz vs. 10 Hz) and current (0.5 mA vs. 1.0 mA). A distinct pattern of cortical activation was found for each nerve. The higher stimulation current resulted in a dramatic increase in the level of cortical activation. The higher stimulation frequency resulted in both increases and attenuation of cortical activation in different regions of the brain, depending on which nerve was stimulated. PMID:17969116

Cho, Younghoon R.; Pawela, Christopher P.; Li, Rupeng; Kao, Dennis; Schulte, Marie L.; Runquist, Matthew L.; Yan, Ji-Geng; Matloub, Hani S.; Jaradeh, Safwan S.; Hudetz, Anthony G.; Hyde, James S.

2008-01-01

89

Functional recovery of severe obturator and femoral nerve injuries after lateral retroperitoneal transpsoas surgery.  

PubMed

The minimally invasive lateral retroperitoneal transpsoas approach is a popular fusion technique. However, potential complications include injury to the lumbar plexus nerves, bowel, and vasculature, the most common of which are injuries to the lumbar plexus. The femoral nerve is particularly vulnerable because of its size and location; injury to the femoral nerve has significant clinical implications because of its extensive sensory and motor innervation of the lower extremities. The authors present an interesting case of a 49-year-old male patient in whom femoral and obturator nerve functional recovery unexpectedly occurred 364 days after the nerves had been injured during lateral retroperitoneal transpsoas surgery. Chronological video and electrodiagnostic findings demonstrate evidence of recovery. Classification and mechanisms of nerve injury and nerve regeneration are discussed. PMID:23432325

Ahmadian, Amir; Abel, Naomi; Uribe, Juan S

2013-04-01

90

Low-level laser treatment improves longstanding sensory aberrations in the inferior alveolar nerve following surgical trauma  

NASA Astrophysics Data System (ADS)

The incidence of inferior alveolar nerve (IAN) damage following removal of 3rd molar teeth or saggital split osteotomy has been reported as high as up to 5.5% and 100% respectively. Sensory aberrations in the IAN persisting for longer than 6 months leave some degree of permanent defect. Low level laser treatment (LLL) has a reported beneficial effect on regeneration of traumatically injured nerves. The purpose of this double blind clinical trial was to examine the effects of LLL using a GaAlAs laser (820 nm, Ronvig, Denmark) on touch and temperature sensory perception following a longstanding post surgical IAN injury. Thirteen patients were divided into two groups, one of which received real LLL (4 by 6 J per treatment along the distribution of the IAN to a total of 20 treatments during a time period between 36 - 69 days) and the other equivalent placebo LLL. The degree of mechanoreceptor injury as assessed by Semmes Weinstein Monofilaments (North Coast Medical, USA) were comparable in the two groups prior to treatment (p equals 0.9). Subsequent to LLL the real laser treatment group showed a significant improvement in mechanoreceptor sensory testing (p equals 0.01) as manifested by a decrease in load threshold (g) necessary to elicit a response from the most damaged area. The placebo LLL group showed no significant improvement, In addition, the real LLL group reported a subjective improvement in sensory function too. The degree of thermal sensitivity disability as assessed using a thermotester (Philips, Sweden) was comparable between the two groups prior to LLL p equals 0.5). However, there was no significant improvement in thermal sensitivity post LLL for either the real or placebo laser treated groups. In conclusion, GaAlAs LLL can improve mechanoreceptor perception in longstanding sensory aberration in the IAN.

Khullar, Shelley M.; Brodin, P.; Barkvoll, P.; Haanoes, H. R.

1996-01-01

91

Amplitude of sensory nerve action potential in early stage diabetic peripheral neuropathy: an analysis of 500 cases  

PubMed Central

Early diagnosis of diabetic peripheral neuropathy is important for the successful treatment of diabetes mellitus. In the present study, we recruited 500 diabetic patients from the Fourth Affiliated Hospital of Kunming Medical University in China from June 2008 to September 2013: 221 cases showed symptoms of peripheral neuropathy (symptomatic group) and 279 cases had no symptoms of peripheral impairment (asymptomatic group). One hundred healthy control subjects were also recruited. Nerve conduction studies revealed that distal motor latency was longer, sensory nerve conduction velocity was slower, and sensory nerve action potential and amplitude of compound muscle action potential were significantly lower in the median, ulnar, posterior tibial and common peroneal nerve in the diabetic groups compared with control subjects. Moreover, the alterations were more obvious in patients with symptoms of peripheral neuropathy. Of the 500 diabetic patients, neural conduction abnormalities were detected in 358 cases (71.6%), among which impairment of the common peroneal nerve was most prominent. Sensory nerve abnormality was more obvious than motor nerve abnormality in the diabetic groups. The amplitude of sensory nerve action potential was the most sensitive measure of peripheral neuropathy. Our results reveal that varying degrees of nerve conduction changes are present in the early, asymptomatic stage of diabetic peripheral neuropathy. PMID:25221597

Zhang, Yunqian; Li, Jintao; Wang, Tingjuan; Wang, Jianlin

2014-01-01

92

Modelled temperature-dependent excitability behaviour of a generalised human peripheral sensory nerve fibre  

Microsoft Academic Search

The objective of this study was to determine if a recently developed human Ranvier node model, which is based on a modified\\u000a version of the Hodgkin–Huxley model, could predict the excitability behaviour in human peripheral sensory nerve fibres with\\u000a diameters ranging from 5.0 to 15.0 ?m. The Ranvier node model was extended to include a persistent sodium current and was

Jacoba E. Smit; Tania Hanekom; Johan J. Hanekom

2009-01-01

93

Hyperglycemia- and neuropathy-induced changes in mitochondria within sensory nerves  

PubMed Central

Objective This study focused on altered mitochondrial dynamics as a potential mechanism for diabetic peripheral neuropathy (DPN). We employed both an in vitro sensory neuron model and an in situ analysis of human intraepidermal nerve fibers (IENFs) from cutaneous biopsies to measure alterations in the size distribution of mitochondria as a result of hyperglycemia and diabetes, respectively. Methods Neurite- and nerve-specific mitochondrial signals within cultured rodent sensory neurons and human IENFs were measured by employing a three-dimensional visualization and quantification technique. Skin biopsies from distal thigh (DT) and distal leg (DL) were analyzed from three groups of patients; patients with diabetes and no DPN, patients with diabetes and confirmed DPN, and healthy controls. Results This analysis demonstrated an increase in mitochondria distributed within the neurites of cultured sensory neurons exposed to hyperglycemic conditions. Similar changes were observed within IENFs of the DT in DPN patients compared to controls. This change was represented by a significant shift in the size frequency distribution of mitochondria toward larger mitochondria volumes within DT nerves of DPN patients. There was a length-dependent difference in mitochondria within IENFs. Distal leg IENFs from control patients had a significant shift toward larger volumes of mitochondrial signal compared to DT IENFs. Interpretation The results of this study support the hypothesis that altered mitochondrial dynamics may contribute to DPN pathogenesis. Future studies will examine the potential mechanisms that are responsible for mitochondrial changes within IENFs and its effect on DPN pathogenesis. PMID:25493271

Hamid, Hussein S; Mervak, Colin M; Münch, Alexandra E; Robell, Nicholas J; Hayes, John M; Porzio, Michael T; Singleton, J Robinson; Smith, A Gordon; Feldman, Eva L; Lentz, Stephen I

2014-01-01

94

Sigma-1 receptor expression in sensory neurons and the effect of painful peripheral nerve injury  

PubMed Central

Background The sigma-1 receptor (?1R), an endoplasmic reticulum chaperone protein, is widely distributed and regulates numerous intracellular processes in neurons. Nerve injury alters the structure and function of axotomized dorsal root ganglion (DRG) neurons, contributing to the development of pain. The ?1R is enriched in the spinal cord and modulates pain after peripheral nerve injury. However, ?1R expression in the DRG has not been studied. We therefore characterized ?1R expression in DRGs at baseline and following spinal nerve ligation (SNL) in rats. Results Immunohistochemical (IHC) studies in DRG sections show ?1R in both neuronal somata and satellite glial cells. The punctate distribution of ?1R in the neuronal cytoplasm suggests expression in the endoplasmic reticulum. When classified by neuronal size, large neurons (>1300 ?m) showed higher levels of ?1R staining than other groups (700-1300 ?m, <700 ?m). Comparing ?1R expression in neuronal groups characterized by expression of calcitonin gene-related peptide (CGRP), isolectin-B4 (IB4) and neurofilament-200 (NF-200), we found ?1R expression in all three neuronal subpopulations, with highest levels of ?1R expression in the NF-200 group. After SNL, lysates from L5 DRGs that contains axotomized neurons showed decreased ?1R protein but unaffected transcript level, compared with Control DRGs. IHC images also showed decreased ?1R protein expression, in SNL L5 DRGs, and to a lesser extent in the neighboring SNL L4 DRGs. Neurons labeled by CGRP and NF-200 showed decreased ?1R expression in L5 and, to a lesser extent, L4 DRGs. In IB4-labeled neurons, ?1R expression decreased only in axotomized L5 DRGs. Satellite cells also showed decreased ?1R expression in L5 DRGs after SNL. Conclusions Our data show that ?1R is present in both sensory neurons and satellite cells in rat DRGs. Expression of ?1R is down-regulated in axotomized neurons as well as in their accompanying satellite glial cells, while neighboring uninjured neurons show a lesser down-regulation. Therefore, elevated ?1R expression in neuropathic pain is not an explanation for pain relief after ?1R blockade. This implies that increased levels of endogenous ?1R agonists may play a role, and diminished neuroprotection from loss of glial ?1R may be a contributing factor. PMID:24015960

2013-01-01

95

Peripheral nerve regeneration and NGF-dependent neurite outgrowth of adult sensory neurons converge on STAT3 phosphorylation downstream of neuropoietic cytokine receptor gp130.  

PubMed

After nerve injury, adult sensory neurons can regenerate peripheral axons and reconnect with their target tissue. Initiation of outgrowth, as well as elongation of neurites over long distances, depends on the signaling of receptors for neurotrophic growth factors. Here, we investigated the importance of gp130, the signaling subunit of neuropoietic cytokine receptors in peripheral nerve regeneration. After sciatic nerve crush, functional recovery in vivo was retarded in SNS-gp130(-/-) mice, which specifically lack gp130 in sensory neurons. Correspondingly, a significantly reduced number of free nerve endings was detected in glabrous skin from SNS-gp130(-/-) compared with control mice after nerve crush. Neurite outgrowth and STAT3 activation in vitro were severely reduced in cultures in gp130-deficient cultured neurons. Surprisingly, in neurons obtained from SNS-gp130(-/-) mice the increase in neurite length was reduced not only in response to neuropoietic cytokine ligands of gp130 but also to nerve growth factor (NGF), which does not bind to gp130-containing receptors. Neurite outgrowth in the absence of neurotrophic factors was partially rescued in gp130-deficient neurons by leptin, which activates STAT3 downstream of leptic receptor and independent of gp130. The neurite outgrowth response of gp130-deficient neurons to NGF was fully restored in the presence of leptin. Based on these findings, gp130 signaling via STAT3 activation is suggested not only to be an important regulator of peripheral nerve regeneration in vitro and in vivo, but as determining factor for the growth promoting action of NGF in adult sensory neurons. PMID:25253866

Quarta, Serena; Baeumer, Bastian E; Scherbakov, Nadja; Andratsch, Manfred; Rose-John, Stefan; Dechant, Georg; Bandtlow, Christine E; Kress, Michaela

2014-09-24

96

Peripheral Nerve Regeneration and NGF-Dependent Neurite Outgrowth of Adult Sensory Neurons Converge on STAT3 Phosphorylation Downstream of Neuropoietic Cytokine Receptor gp130  

PubMed Central

After nerve injury, adult sensory neurons can regenerate peripheral axons and reconnect with their target tissue. Initiation of outgrowth, as well as elongation of neurites over long distances, depends on the signaling of receptors for neurotrophic growth factors. Here, we investigated the importance of gp130, the signaling subunit of neuropoietic cytokine receptors in peripheral nerve regeneration. After sciatic nerve crush, functional recovery in vivo was retarded in SNS-gp130?/? mice, which specifically lack gp130 in sensory neurons. Correspondingly, a significantly reduced number of free nerve endings was detected in glabrous skin from SNS-gp130?/? compared with control mice after nerve crush. Neurite outgrowth and STAT3 activation in vitro were severely reduced in cultures in gp130-deficient cultured neurons. Surprisingly, in neurons obtained from SNS-gp130?/? mice the increase in neurite length was reduced not only in response to neuropoietic cytokine ligands of gp130 but also to nerve growth factor (NGF), which does not bind to gp130-containing receptors. Neurite outgrowth in the absence of neurotrophic factors was partially rescued in gp130-deficient neurons by leptin, which activates STAT3 downstream of leptic receptor and independent of gp130. The neurite outgrowth response of gp130-deficient neurons to NGF was fully restored in the presence of leptin. Based on these findings, gp130 signaling via STAT3 activation is suggested not only to be an important regulator of peripheral nerve regeneration in vitro and in vivo, but as determining factor for the growth promoting action of NGF in adult sensory neurons. PMID:25253866

Quarta, Serena; Baeumer, Bastian E.; Scherbakov, Nadja; Andratsch, Manfred; Rose-John, Stefan; Dechant, Georg; Bandtlow, Christine E.

2014-01-01

97

Secretion of Growth Hormone in Response to Muscle Sensory Nerve Stimulation  

NASA Technical Reports Server (NTRS)

Growth hormone (GH) secretion is stimulated by aerobic and resistive exercise and inhibited by exposure to actual or simulated (bedrest, hindlimb suspension) microgravity. Moreover, hypothalamic growth hormone-releasing factor (GRF) and preproGRF mRNA are markedly decreased in spaceflight rats. These observations suggest that reduced sensory input from inactive muscles may contribute to the reduced secretion of GH seen in "0 G". Thus, the aim of this study was to determine the effect of muscle sensory nerve stimulation on secretion of GH. Fed male Wistar rats (304 +/- 23 g) were anesthetized (pentobarbital) and the right peroneal (Pe), tibial (T), and sural (S) nerves were cut. Electrical stimulation of the distal (D) or proximal (P) ends of the nerves was implemented for 15 min. to mimic the EMG activity patterns of ankle extensor muscles of a rat walking 1.5 mph. The rats were bled by cardiac puncture and their anterior pituitaries collected. Pituitary and plasma bioactive (BGH) and immunoactive (IGH) GH were measured by bioassay and RIA.

Grindeland, Richard E.; Roy, R. R.; Edgerton, V. R.; Gosselink, K. L.; Grossman, E. J.; Sawchenko, P. E.; Wade, Charles E. (Technical Monitor)

1994-01-01

98

Intervertebral disc, sensory nerves and neurotrophins: who is who in discogenic pain?  

PubMed

The normal intervertebral disc (IVD) is a poorly innervated organ supplied only by sensory (mainly nociceptive) and postganglionic sympathetic (vasomotor efferents) nerve fibers. Interestingly, upon degeneration, the IVD becomes densely innervated even in regions that in normal conditions lack innervation. This increased innervation has been associated with pain of IVD origin. The mechanisms responsible for nerve growth and hyperinnervation of pathological IVDs have not been fully elucidated. Among the molecules that are presumably involved in this process are some members of the family of neurotrophins (NTs), which are known to have both neurotrophic and neurotropic properties and regulate the density and distribution of nerve fibers in peripheral tissues. NTs and their receptors are expressed in healthy IVDs but much higher levels have been observed in pathological IVDs, thus suggesting a correlation between levels of expression of NTs and density of innervation in IVDs. In addition, NTs also play a role in inflammatory responses and pain transmission by increasing the expression of pain-related peptides and modulating synapses of nociceptive neurons at the spinal cord. This article reviews current knowledge about the innervation of IVDs, NTs and NT receptors, expression of NTs and their receptors in IVDs as well as in the sensory neurons innervating the IVDs, the proinflammatory role of NTs, NTs as nociception regulators, and the potential network of discogenic pain involving NTs. PMID:20456524

García-Cosamalón, José; del Valle, Miguel E; Calavia, Marta G; García-Suárez, Olivia; López-Muńiz, Alfonso; Otero, Jesús; Vega, José A

2010-07-01

99

Cortical Brain Mapping of Peripheral Nerves Using Functional Magnetic Resonance Imaging in a Rodent Model  

PubMed Central

The regions of the body have cortical and subcortical representation in proportion to their degree of innervation. The rat forepaw has been studied extensively in recent years using functional magnetic resonance imaging (fMRI)—typically by stimulation using electrodes directly inserted into the skin of the forepaw. Here, we stimulate using surgically implanted electrodes. A major distinction is that stimulation of the skin of the forepaw is mostly sensory, whereas direct nerve stimulation reveals not only the sensory system but also deep brain structures associated with motor activity. In this paper, we seek to define both the motor and sensory cortical and subcortical representations associated with the four major nerves of the rodent upper extremity. We electrically stimulated each nerve (median, ulnar, radial, and musculocutaneous) during fMRI acquisition using a 9.4T Bruker scanner. A current level of 0.5-1.0 mA and a frequency of 5 Hz were used while keeping the duration constant. A distinct pattern of cortical activation was found for each nerve that can be correlated with known sensorimotor afferent and efferent pathways to the rat forepaw. This direct nerve stimulation rat model can provide insight into peripheral nerve injury. PMID:18924070

Cho, Younghoon R.; Jones, Seth R.; Pawela, Christopher P.; Li, Rupeng; Kao, Dennis S.; Schulte, Marie L.; Runquist, Matthew L.; Yan, Ji-Geng; Hudetz, Anthony G.; Jaradeh, Safwan S.; Hyde, James S.; Matloub, Hani S.

2008-01-01

100

Cutaneous sensory nerve as a substitute for auditory nerve in solving deaf-mutes’ hearing problem: an innovation in multi-channel-array skin-hearing technology  

PubMed Central

The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to substitute for the auditory nerve to help deaf-mutes to hear sound. This paper introduces a new solution, multi-channel-array skin-hearing technology, to solve the problem of speech discrimination. Based on the filtering principle of hair cells, external voice signals at different frequencies are converted to current signals at corresponding frequencies using electronic multi-channel bandpass filtering technology. Different positions on the skin can be stimulated by the electrode array, allowing the perception and discrimination of external speech signals to be determined by the skin response to the current signals. Through voice frequency analysis, the frequency range of the band-pass filter can also be determined. These findings demonstrate that the sensory nerves in the skin can help to transfer the voice signal and to distinguish the speech signal, suggesting that the skin sensory nerves are good candidates for the replacement of the auditory nerve in addressing deaf-mutes’ hearing problems. Scientific hearing experiments can be more safely performed on the skin. Compared with the artificial cochlea, multi-channel-array skin-hearing aids have lower operation risk in use, are cheaper and are more easily popularized. PMID:25317171

Li, Jianwen; Li, Yan; Zhang, Ming; Ma, Weifang; Ma, Xuezong

2014-01-01

101

Cutaneous sensory nerve as a substitute for auditory nerve in solving deaf-mutes' hearing problem: an innovation in multi-channel-array skin-hearing technology.  

PubMed

The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to substitute for the auditory nerve to help deaf-mutes to hear sound. This paper introduces a new solution, multi-channel-array skin-hearing technology, to solve the problem of speech discrimination. Based on the filtering principle of hair cells, external voice signals at different frequencies are converted to current signals at corresponding frequencies using electronic multi-channel bandpass filtering technology. Different positions on the skin can be stimulated by the electrode array, allowing the perception and discrimination of external speech signals to be determined by the skin response to the current signals. Through voice frequency analysis, the frequency range of the band-pass filter can also be determined. These findings demonstrate that the sensory nerves in the skin can help to transfer the voice signal and to distinguish the speech signal, suggesting that the skin sensory nerves are good candidates for the replacement of the auditory nerve in addressing deaf-mutes' hearing problems. Scientific hearing experiments can be more safely performed on the skin. Compared with the artificial cochlea, multi-channel-array skin-hearing aids have lower operation risk in use, are cheaper and are more easily popularized. PMID:25317171

Li, Jianwen; Li, Yan; Zhang, Ming; Ma, Weifang; Ma, Xuezong

2014-08-15

102

Renal sensory and sympathetic nerves reinnervate the kidney in a similar time-dependent fashion after renal denervation in rats  

PubMed Central

Efferent renal sympathetic nerves reinnervate the kidney after renal denervation in animals and humans. Therefore, the long-term reduction in arterial pressure following renal denervation in drug-resistant hypertensive patients has been attributed to lack of afferent renal sensory reinnervation. However, afferent sensory reinnervation of any organ, including the kidney, is an understudied question. Therefore, we analyzed the time course of sympathetic and sensory reinnervation at multiple time points (1, 4, and 5 days and 1, 2, 3, 4, 6, 9, and 12 wk) after renal denervation in normal Sprague-Dawley rats. Sympathetic and sensory innervation in the innervated and contralateral denervated kidney was determined as optical density (ImageJ) of the sympathetic and sensory nerves identified by immunohistochemistry using antibodies against markers for sympathetic nerves [neuropeptide Y (NPY) and tyrosine hydroxylase (TH)] and sensory nerves [substance P and calcitonin gene-related peptide (CGRP)]. In denervated kidneys, the optical density of NPY-immunoreactive (ir) fibers in the renal cortex and substance P-ir fibers in the pelvic wall was 6, 39, and 100% and 8, 47, and 100%, respectively, of that in the contralateral innervated kidney at 4 days, 4 wk, and 12 wk after denervation. Linear regression analysis of the optical density of the ratio of the denervated/innervated kidney versus time yielded similar intercept and slope values for NPY-ir, TH-ir, substance P-ir, and CGRP-ir fibers (all R2 > 0.76). In conclusion, in normotensive rats, reinnervation of the renal sensory nerves occurs over the same time course as reinnervation of the renal sympathetic nerves, both being complete at 9 to 12 wk following renal denervation. PMID:23408032

Mulder, Jan; Hökfelt, Tomas; Knuepfer, Mark M.

2013-01-01

103

Clinical utility of tibial motor and sensory nerve conduction studies with motor recording from the flexor hallucis brevis: a methodological and reliability study  

PubMed Central

Background Standard tibial motor nerve conduction measures are established with recording from the abductor hallucis. This technique is often technically challenging and clinicians have difficulty interpreting the information particularly in the short segment needed to assess focal tibial nerve entrapment at the medial ankle as occurs in posterior tarsal tunnel syndrome. The flexor hallucis brevis (FHB) has been described as an alternative site for recording tibial nerve function in those with posterior tarsal tunnel syndrome. Normative data has not been established for this technique. This pilot study describes the technique in detail. In addition we provide reference values for medial and lateral plantar orthodromic sensory measures and assessed intrarater reliability for all measures. Methods Eighty healthy female participants took part, and 39 returned for serial testing at 4 time points. Mean values ± SD were recorded for nerve conduction measures, and coefficient of variation as well as intraclass correlation coefficients (ICC) were calculated. Results Motor latency, amplitude and velocity values for the FHB were 4.1 ± 0.9 msec, 8.0 ± 3.0 mV and 45.6 ± 3.4 m/s, respectively. Sensory latencies, amplitudes, and velocities, respectively, were 2.8 ± 0.3 msec, 26.7 ± 10.1 ?V, and 41.4 ± 3.5 m/s for the medial plantar nerve and 3.2 ± 0.5 msec, 13.3 ± 4.7 ?V, and 44.3 ± 4.0 msec for the lateral plantar nerve. All values demonstrated significant ICC values (P ? 0.007). Conclusion Motor recording from the FHB provides technically clear waveforms that allow for an improved ability to assess tibial nerve function in the short segments used to assess tarsal tunnel syndrome. The reported means will begin to establish normal values for this technique. PMID:21609432

2011-01-01

104

Identifying motor and sensory myelinated axons in rabbit peripheral nerves by histochemical staining for carbonic anhydrase and cholinesterase activities  

NASA Technical Reports Server (NTRS)

Carbonic anhydrase (CA) and cholinesterase (CE) histochemical staining of rabbit spinal nerve roots and dorsal root ganglia demonstrated that among the reactive myeliated axons, with minor exceptions, sensory axons were CA positive and CE negative whereas motor axons were CA negative and CE positive. The high specificity was achieved by adjusting reaction conditions to stain subpopulations of myelinated axons selectively while leaving 50 percent or so unstained. Fixation with glutaraldehyde appeared necessary for achieving selectivity. Following sciatic nerve transection, the reciprocal staining pattern persisted in damaged axons and their regenerating processes which formed neuromas within the proximal nerve stump. Within the neuromas, CA-stained sensory processes were elaborated earlier and in greater numbers than CE-stained regenerating motor processes. The present results indicate that histochemical axon typing can be exploited to reveal heterogeneous responses of motor and sensory axons to injury.

Riley, Danny A.; Sanger, James R.; Matloub, Hani S.; Yousif, N. John; Bain, James L. W.

1988-01-01

105

Functional and structural nerve fiber findings in heterozygote patients with Fabry disease.  

PubMed

Fabry disease is an X-linked inherited lysosomal disorder with dysfunction of the lysosomal enzyme alpha-galactosidase A causing accumulation of glycolipids in multiple organs including the nervous system. Pain and somatosensory disturbances are prominent manifestations of this disease. Until recently disease manifestations in female carriers of Fabry disease have been questioned. To explore the frequency of symptoms and the functional and structural involvement of the nervous system in female patients we examined the presence of pain, manifestations of peripheral neuropathy and nerve density in skin biopsies in 19 female patients with Fabry disease and 19 sex- and age-matched controls. Diaries, quantitative sensory testing, neurophysiologic tests and skin biopsies were performed. Daily pain was present in 63% of patients, with a median VAS score of 4.0. Tactile detection threshold and pressure pain threshold were lower and cold detection thresholds increased in patients. Sensory nerve action potential amplitude and maximal sensory conduction velocity were not different, whereas there was a highly significant reduction in intraepidermal nerve fiber density. We found no correlation between pain VAS score, quantitative sensory testing and intraepidermal nerve fiber density. Our study demonstrates that careful evaluation of symptoms in female Fabry patients is important as small fiber disease manifestations are present, which in some cases is only detected by skin biopsy. PMID:19665302

Torvin Mřller, Anette; Winther Bach, Flemming; Feldt-Rasmussen, Ulla; Rasmussen, Ase; Hasholt, Lis; Lan, He; Sommer, Claudia; Křlvraa, Steen; Ballegaard, Martin; Staehelin Jensen, Troels

2009-09-01

106

Impaired responsiveness of renal sensory nerves in streptozotocin-treated rats and obese Zucker diabetic fatty rats: role of angiotensin.  

PubMed

Increasing afferent renal nerve activity decreases efferent renal nerve activity and increases urinary sodium excretion. Activation of renal pelvic mechanosensory nerves is impaired in streptozotocin (STZ)-treated rats (model of type 1 diabetes). Decreased activation of renal sensory nerves would lead to increased efferent renal nerve activity, sodium retention, and hypertension. We examined whether the reduced activation of renal sensory nerves in STZ rats was due to increased renal angiotensin activity and whether activation of the renal sensory nerves was impaired in obese Zucker diabetic fatty (ZDF) rats (model of type 2 diabetes). In an isolated renal pelvic wall preparation from rats treated with STZ for 2 wk, PGE2 failed to increase the release of substance P, from 5 +/- 1 to 6 +/- 1 pg/min. In pelvises from sham STZ rats, PGE2 increased substance P release from 6 +/- 1 to 13 +/- 2 pg/min. Adding losartan to the incubation bath increased PGE2-mediated release of substance P in STZ rats, from 5 +/- 1 to 10 +/- 2 pg/min, but had no effect in sham STZ rats. In pelvises from obese ZDF rats (22-46 wk old), PGE2 increased substance P release from 12.0 +/- 1.2 to 18.3 +/- 1.2 pg/min, which was less than that from lean ZDF rats (10.3 +/- 1.6 to 22.5 +/- 2.4 pg/min). Losartan had no effect on the PGE2-mediated substance P release in obese or lean ZDF rats. We conclude that the mechanisms involved in the decreased responsiveness of the renal sensory nerves in STZ rats involve activation of the renin angiotensin system in STZ but not in obese ZDF rats. PMID:18199587

Kopp, Ulla C; Cicha, Michael Z; Yorek, Mark A

2008-03-01

107

Functional recovery following peripheral nerve injury in the transgenic Thy1-GFP rat.  

PubMed

Transgenic mice have been previously used to assess nerve regeneration following peripheral nerve injury. However, mouse models are limited by their small caliber nerves, short nerve lengths, and their inability to fully participate during behavioral assessments. The transgenic Thy1 GFP rat is a novel transgenic rat model designed to assess regeneration following peripheral nerve injury. However, return of functional and behavioral recovery following nerve injury has not yet been evaluated in these rats. In this study, we ask whether differences in anatomy, recovery of locomotion, myological, and histomorphological measures exist between transgenic Thy1 GFP rats when compared to wild type (WT) Sprague Dawley rats following unilateral sciatic nerve injury. We found that both motor and sensory neuronal architecture, overground and skilled locomotion, muscle force, motor unit number estimation (MUNE) and wet muscle weights, and histomorphometric assessments are similar between both genetic phenotypes. Overall, these data support the use of the transgenic Thy1-GFP rat in experiments assessing functional and behavioral recovery following nerve injury and repair. PMID:24028190

Kemp, Stephen W P; Phua, Peter D; Stanoulis, Krisanne N; Wood, Matthew D; Liu, Edward H; Gordon, Tessa; Borschel, Gregory H

2013-09-01

108

Endogenous NGF and Nerve Impulses Regulate the Collateral Sprouting of Sensory Axons in the Skin of the Adult Rat  

Microsoft Academic Search

We have investigated the co-involvement of enclogenous NGF and impulses in the collateral sprouting of cutaneous sensory nerves in adult rats, specifically the A&axons in- volved in mechanonociception and the C-fibers that mediate heat nociception. Their collateral sprouting was measured by the progressive expansion, respectively, of the behav- iorally defined \\

Jack Diamond; Michael Holmes; Michael Coughlin

1992-01-01

109

The effect of aging on the density of the sensory nerve fiber innervation of bone and acute skeletal pain  

PubMed Central

As humans age there is a decline in most sensory systems including vision, hearing, taste, smell, and tactile acuity. In contrast, the frequency and severity of musculoskeletal pain generally increases with age. To determine whether the density of sensory nerve fibers that transduce skeletal pain changes with age, calcitonin gene related peptide (CGRP) and neurofilament 200 kDa (NF200) sensory nerve fibers that innervate the femur were examined in the femurs of young (4 month old), middle-aged (13 month) and old (36 month) male F344/BNF1 rats. Whereas the bone quality showed a significant age-related decline, the density of CGRP+ and NF200+ nerve fibers that innervate the bone remained remarkably unchanged as well as the severity of acute skeletal fracture pain. Thus, while bone mass, quality and strength undergo a significant decline with age, the density of sensory nerve fibers that transduce noxious stimuli remain largely intact. These data may in part explain why musculoskeletal pain increases with age. PMID:20947214

Jimenez-Andrade, Juan M.; Mantyh, William G.; Bloom, Aaron P.; Freeman, Katie T.; Ghilardi, Joseph R.; Kuskowski, Michael A.; Mantyh, Patrick W.

2010-01-01

110

Impulses in the sensory nerves in response to stimulation of the skin receptors of immunized animals with antigen  

Microsoft Academic Search

The skin receptors of the immunized animals react to specific antigens for a more prolonged time and often with greater intensity. The reaction is more prolonged, the frequency of the bioelectrical potential oscillations of the sensory nerves becomes greater. This is, probably, one of the most important factors showing the changed reaction of the immunized animals to the administration of

A. N. Gordienko; B. A. Saakov; I. M. Bondarev

1959-01-01

111

Nerve Growth Factor Antiserum Induces Axotomy-Like Changes in Neuropeptide Expression in Intact Sympathetic and Sensory Neurons  

Microsoft Academic Search

Axonal transection of adult sympathetic and sensory neurons leads to a decrease in their content of target-derived nerve growth factor (NGF) and to dramatic changes in the expression of several neuropeptides and enzymes involved in transmitter biosynthesis. For example, axotomy of sympathetic neurons in the superior cervical ganglion (SCG) dramatically increases levels of galanin, vasoactive intestinal peptide (VIP), and sub-

Annette M. Shadiack; Yi Sun; Richard E. Zigmond

2001-01-01

112

Diphtheritic neuropathy, an analysis based on muscle and nerve biopsy and repeated neurophysiological and autonomic function tests.  

PubMed Central

A patient with diphtheritic neuropathy was investigated with repeated tests of parasympathetic and sympathetic vasomotor and sudomotor functions for one year after the onset of symptoms. Somatic nerve function was tested with nerve conduction studies and an index based on ten variables was used to follow the course of the neuropathy. Sural nerve and anterior tibial muscle biopsies were performed. A severe but shortlasting impairment of the parasympathetic vagal reflex arc was found. The recovery of this function paralleled the clinical course. Sympathetic functions were normal. The neurophysiological variables of somatic nerve function showed signs of a mainly demyelinating mixed sensory/motor neuropathy. The recovery of these variables was slow. The nerve and muscle biopsies demonstrated mild changes consistent with a mixed, demyelinating, non-inflammatory neuropathy. Images PMID:2549201

Solders, G; Nennesmo, I; Persson, A

1989-01-01

113

Functional recovery after peripheral nerve injury and implantation of a collagen guide.  

PubMed

Although surgery techniques improved over the years, the clinical results of peripheral nerve repair remain unsatisfactory. In the present study, we compare the results of a collagen nerve guide conduit to the standard clinical procedure of nerve autografting to promote repair of transected peripheral nerves. We assessed behavioral and functional sensori-motor recovery in a rat model of peroneal nerve transection. A 1cm segment of the peroneal nerve innervating the Tibialis anterior muscle was removed and immediately replaced by a new biodegradable nerve guide fabricated from highly purified type I+III collagens derived from porcine skin. Four groups of animals were included: control animals (C, n=12), transected animals grafted with either an autologous nerve graft (Gold Standard; GS, n=12) or a collagen tube filled with an acellular skeletal muscle matrix (Tube-Muscle; TM, n=12) or an empty collagen tube (Collagen-Tube; CT, n=12). We observed that 1) the locomotor recovery pattern, analyzed with kinetic parameters and peroneal functional index, was superior in the GS and CT groups; 2) a muscle contraction was obtained in all groups after stimulation of the proximal nerve but the mechanical muscle properties (twitch and tetanus threshold) parameters indicated a fast to slow fiber transition in all operated groups; 3) the muscular atrophy was greater in animals from TM group; 4) the metabosensitive afferent responses to electrically induced fatigue and to two chemical agents (KCl and lactic acid) was altered in GS, CT and TM groups; 5) the empty collagen tube supported motor axonal regeneration. Altogether, these data indicate that motor axonal regeneration and locomotor recovery can be obtained with the insertion of the collagen tube RevolNerv. Future studies may include engineered conduits that mimic as closely as possible the internal organization of uninjured nerve. PMID:18929405

Alluin, Olivier; Wittmann, Catherine; Marqueste, Tanguy; Chabas, Jean-François; Garcia, Stéphane; Lavaut, Marie-Noëlle; Guinard, Didier; Feron, François; Decherchi, Patrick

2009-01-01

114

Self-powered sensory nerve system for civil structures using hybrid forisome actuators  

NASA Astrophysics Data System (ADS)

In order to provide a true distributed sensor and control system for civil structures, we have developed a Structural Nervous System that mimics key attributes of a human nervous system. This nervous system is made up of building blocks that are designed based on mechanoreceptors as a fundamentally new approach for the development of a structural health monitoring and diagnostic system that utilizes the recently discovered plant-protein forisomes, a novel non-living biological material capable of sensing and actuation. In particular, our research has been focused on producing a sensory nervous system for civil structures by using forisomes as the mechanoreceptors, nerve fibers, neuronal pools, and spinocervical tract to the nodal and central processing units. This paper will present up to date results of our research, including the design and analysis of the structural nervous system.

Shoureshi, Rahmat A.; Shen, Amy

2006-03-01

115

Behavioural and histological observations of sensory impairment caused by tight ligation of the trigeminal nerve in mice.  

PubMed

Dental treatments sometimes cause sensory impairment, especially in the region innervated by the third division of the trigeminal nerve. The most frequent symptoms are loss of sensation and abnormal sensation. Although most studies have addressed the neuropathic symptom "allodynia" using experimental animal models of the infraorbital nerve, there is little information regarding the sensory impairment that frequently occurs clinically. Therefore, different experimental models are required to clarify the mechanisms of the clinical effects, and previous experimental models have been limited to rats. Here, we report a sensory impairment model in mice whose mechanical touch threshold increased after tight ligation of the mental nerve. Habituation before surgery by mechanical touching of the face enabled us to observe the long-term chronological changes in sensation. The mechanical touch thresholds within the mental nerve region were measured for 70 postoperative (PO) days. Changes in the distribution of substance P (SP) were evaluated by immunohistochemistry to clarify the involvement of axonal flow in the sensory impairment and its recovery. The mechanical touch thresholds transiently increased by PO days 2-3, but decreased to the preoperative levels at around PO day 14. Apparent SP immunoreactivity was recognizable on the medial side to the ligation at PO days 2-3 and disappeared at PO day 7. These behavioural and immunohistochemical changes appeared to exhibit similar time courses, suggesting a possible relationship between them. Therefore, we suggest that our experimental mouse model could represent a new model for clarifying the mechanism of the sensory impairment caused by peripheral nerve injury. PMID:19409417

Seino, Hiroyuki; Seo, Kenji; Maeda, Takeyasu; Someya, Genji

2009-06-30

116

Memory Effects and Sensory Integration: An Examination of Sensory Modality Translation Models of Intersensory Functioning.  

ERIC Educational Resources Information Center

The sensory modality of a task and the modality of a retroactive interfering activity were systematically covaried in order to test two models of intersensory functioning. Subjects were 40 ten-year-old boys and girls. (BD)

Marcell, Michael M.; Allen, Terry W.

1978-01-01

117

THE MAJORITY OF MYELINATED AND UNMYELINATED SENSORY NERVE FIBERS THAT INNERVATE BONE EXPRESS THE TROPOMYOSIN RECEPTOR KINASE A  

PubMed Central

Although skeletal pain is a leading cause of chronic pain and disability, relatively little is known about the specific populations of nerve fibers that innervate the skeleton. Recent studies have reported that therapies blocking nerve growth factor (NGF) or its cognate receptor, tropomyosin receptor kinase A (TrkA) are efficacious in attenuating skeletal pain. A potential factor to consider when assessing the analgesic efficacy of targeting NGF-TrkA signaling in a pain state is the fraction of NGF-responsive TrkA+ nociceptors that innervate the tissue from which the pain is arising, as this innervation and the analgesic efficacy of targeting NGF-TrkA signaling may vary considerably from tissue to tissue. To explore this in the skeleton, tissue slices and whole mount preparations of the normal, adult mouse femur were analyzed using immunohistochemistry and confocal microscopy. Analysis of these preparations revealed that 80% of the unmyelinated/thinly myelinated sensory nerve fibers that express calcitonin gene-related peptide (CGRP) and innervate the periosteum, mineralized bone and bone marrow also express TrkA. Similarly, the majority of myelinated sensory nerve fibers that express neurofilament 200 kDa (NF200) which innervate the periosteum, mineralized bone and bone marrow also co-express TrkA. In the normal femur, the relative density of CGRP+, NF200+ and TrkA+ sensory nerve fibers per unit volume is: periosteum > bone marrow > mineralized bone > cartilage with the respective relative densities being 100: 2: 0.1: 0. The observation that the majority of sensory nerve fibers innervating the skeleton express TrkA+, may in part explain why therapies that block NGF/TrkA pathway are highly efficacious in attenuating skeletal pain. PMID:21277945

Castańeda-Corral, Gabriela; Jimenez-Andrade, Juan M.; Bloom, Aaron P.; Taylor, Reid N.; Mantyh, William G.; Kaczmarska, Magdalena J.; Ghilardi, Joseph R.; Mantyh, Patrick W.

2011-01-01

118

Implementation of Linear Sensory Signaling via Multiple Coordinated Mechanisms at Central Vestibular Nerve Synapses.  

PubMed

Signal transfer in neural circuits is dynamically modified by the recent history of neuronal activity. Short-term plasticity endows synapses with nonlinear transmission properties, yet synapses in sensory and motor circuits are capable of signaling linearly over a wide range of presynaptic firing rates. How do such synapses achieve rate-invariant transmission despite history-dependent nonlinearities? Here, ultrastructural, biophysical, and computational analyses demonstrate that concerted molecular, anatomical, and physiological refinements are required for central vestibular nerve synapses to linearly transmit rate-coded sensory signals. Vestibular synapses operate in a physiological regime of steady-state depression imposed by tonic firing. Rate-invariant transmission relies on brief presynaptic action potentials that delimit calcium influx, large pools of rapidly mobilized vesicles, multiple low-probability release sites, robust postsynaptic receptor sensitivity, and efficient transmitter clearance. Broadband linear synaptic filtering of head motion signals is thus achieved by coordinately tuned synaptic machinery that maintains physiological operation within inherent cell biological limitations. PMID:25704949

McElvain, Lauren E; Faulstich, Michael; Jeanne, James M; Moore, Jeffrey D; du Lac, Sascha

2015-03-01

119

Adhesiolysis and targeted steroid\\/local anesthetic injection during epiduroscopy alleviates pain and reduces sensory nerve dysfunction in patients with chronic sciatica  

Microsoft Academic Search

Purpose  The aim of this study was to evaluate the effect of adhesiolysis followed by the injection of steroid and local anesthetic\\u000a during epiduroscopy on sensory nerve function, pain, and functional disability in patients with chronic sciatica.\\u000a \\u000a \\u000a \\u000a Methods  Epidural adhesiolysis, using epiduroscopy, followed by the injection of steroid and local anesthetic, was scheduled in 19\\u000a patients with chronic sciatica refractory to lumbar

Tetsuya Sakai; Hiroshi Aoki; Minoru Hojo; Masafumi Takada; Hiroaki Murata; Koji Sumikawa

2008-01-01

120

Electro-acupuncture on functional peripheral nerve regeneration in mice: a behavioural study  

PubMed Central

Background The improvement of axonal regeneration is a major objective in the treatment of peripheral nerve injuries. The aim of this study was to evaluate the effects of electro-acupuncture on the functional recovery of sensorimotor responses following left sciatic nerve crush in mice. Methods Sciatic nerve crush was performed on seven week old female mice. Following the injury, the control group was untreated while the experimental group received an electro-acupuncture application to the injured limb under isoflurane anesthesia at acupoints GB 30 and GB 34. Mechanical and heat sensitivity tests were performed to evaluate sensory recovery. Gait analysis was performed to assess sensorimotor recovery. Results Our results show that normal sensory recovery is achieved within five to six weeks with a two-week period of pain preceding the recovery to normal sensitivity levels. While electro-acupuncture did not accelerate sensory recovery, it did alleviate pain-related behaviour but only when applied during this period. Application before the development of painful symptoms did not prevent their occurrence. The analysis of gait in relation to the sensory tests suggests that the electro-acupuncture specifically improved motor recovery. Conclusions This study demonstrates that electro-acupuncture exerts a positive influence on motor recovery and is efficient in the treatment of pain symptoms that develop during target re-innervation. PMID:22937957

2012-01-01

121

Nerve allograft transplantation for functional restoration of the upper extremity: case series  

PubMed Central

Background Major trauma to the spinal cord or upper extremity often results in severe sensory and motor disturbances from injuries to the brachial plexus and its insertion into the spinal cord. Functional restoration with nerve grafting neurotization and tendon transfers is the mainstay of treatment. Results may be incomplete due to a limited supply of autologous material for nerve grafts. The factors deemed most integral for success are early surgical intervention, reconstruction of all levels of injury, and maximization of the number of axonal conduits per nerve repair. Objective To report the second series of nerve allograft transplantation using cadaveric nerve graft and our experience with living-related nerve transplants. Participants Eight patients, seven men and one woman, average age 23 years (range 18–34), with multi-level brachial plexus injuries were selected for transplantation using either cadaveric allografts or living-related donors. Methods Grafts were harvested and preserved in the University of Wisconsin Cold Storage Solution at 5°C for up to 7 days. The immunosuppressive protocol was initiated at the time of surgery and was discontinued at approximately 1 year, or when signs of regeneration were evident. Parameters for assessment included mechanism of injury, interval between injury and treatment, level(s) of deficit, post-operative return of function, pain relief, need for revision surgery, complications, and improvement in quality of life. Results Surgery was performed using living-related donor grafts in six patients, and cadaveric grafts in two patients. Immunosuppression was tolerated for the duration of treatment in all but one patient in whom early termination occurred due to non-compliance. There were no cases of graft rejection as of most recent follow-up. Seven patients showed signs of regeneration, demonstrated by return of sensory and motor function and/or a migrating Tinel's sign. One patient was non-compliant with the post-operative regimen and experienced minimal return of function despite a reduction in pain. Conclusions Despite the small number of subjects, it appears that nerve allograft transplantation may be performed safely, permitting non-prioritized repair of long-segment peripheral nerve defects and maximizing the number of axonal conduits per nerve repair. For patients with long, multi-level brachial plexus injuries or combined upper and lower extremity nerve deficits, the use of nerve allograft allows a more complete repair that may translate into greater functional restoration than autografting alone. PMID:21675363

Elkwood, Andrew I.; Holland, Neil R.; Arbes, Spiros M.; Rose, Michael I.; Kaufman, Matthew R.; Ashinoff, Russell L.; Parikh, Mona A.; Patel, Tushar R.

2011-01-01

122

How does morphology relate to function in sensory arbors?  

PubMed Central

Sensory dendrites fall into many different morphological and functional classes. Polymodal nociceptors are one subclass of sensory neurons, which are of particular note due to their elaborate dendritic arbors. Complex developmental programs are required to form these arbors, and there is striking conservation of morphology, function, and molecular determinants between vertebrate and invertebrate polymodal nociceptors. Based on these studies, we argue that arbor morphology plays an important role in the function of polymodal nociceptors. Similar associations between form and function may explain the plethora of dendrite morphologies seen among all sensory neurons. PMID:21840610

Hall, David H.; Treinin, Millet

2011-01-01

123

Motor Nerve Transfers to Restore Extrinsic Median Nerve Function: Case Report  

Microsoft Academic Search

Active pronation is important for many activities of daily living. Loss of median nerve function including pronation is a\\u000a rare sequela of humerus fracture. Tendon transfers to restore pronation are reserved for the obstetrical brachial plexus palsy\\u000a patient. Transfer of expendable motor nerves is a treatment modality that can be used to restore active pronation. Nerve transfers\\u000a are advantageous in

Eugene C. Hsiao; Ida K. Fox; Thomas H. Tung; Susan E. Mackinnon

2009-01-01

124

Characterization of neuronal death and functional deficits following nerve injury during the early postnatal developmental period in rats.  

PubMed

In contrast to adult rat nerve injury models, neonatal sciatic nerve crush leads to massive motor and sensory neuron death. Death of these neurons results from both the loss of functional contact between the nerve terminals and their targets, and the inability of immature Schwann cells in the distal stump of the injured nerve to sustain regeneration. However, current dogma holds that little to no motoneuron death occurs in response to nerve crush at postnatal day 5 (P5). The purpose of the current study was to fully characterize the extent of motor and sensory neuronal death and functional recovery following sciatic nerve crush at mid-thigh level in rats at postnatal days 3-30 (P3-P30), and then compare this to adult injured animals. Following nerve crush at P3, motoneuron numbers were reduced to 35% of that of naďve uninjured animals. Animals in the P5 and P7 group also displayed statistically fewer motoneurons than naďve animals. Animals that were injured at P30 or earlier displayed statistically lower sensory neuron counts in the dorsal root ganglion than naďve controls. Surprisingly, complete behavioral recovery was observed exclusively in the P30 and adult injured groups. Similar results were observed in muscle twitch/tetanic force analysis, motor unit number estimation and wet muscle weights. Rats in both the P5 and P7 injury groups displayed significant neuronal death and impaired functional recovery following injury, challenging current dogma and suggesting that severe deficits persist following nerve injury during this early postnatal developmental period. These findings have important implications concerning the timing of neonatal nerve injury in rats. PMID:25592862

Kemp, Stephen W P; Chiang, Cameron D; Liu, Edward H; Wood, Matthew D; Willand, Michael P; Gordon, Tessa; Borschel, Gregory H

2015-01-01

125

Vascular endothelial growth factor promotes anatomical and functional recovery of injured peripheral nerves in the avascular cornea  

PubMed Central

Peripheral nerve injury is a major neurological disorder that can cause severe motor and sensory dysfunction. Neurogenic effects of vascular endothelial growth factor (VEGF) have been found in the central nervous system, and we examined whether VEGF could promote anatomical and functional recovery of peripheral nerves after injury using an avascular corneal nerve injury model. We found that VEGF enhanced neurite elongation in isolated trigeminal ganglion neurons in a dose-dependent manner. This effect was suppressed by neutralizing antibodies for VEGF receptor (VEGFR) 1 and 2 or neuropilin receptor 1 or by VEGFR2 inhibitors (SU 1498 and Ki 8751). In vivo, mice receiving sustained VEGF via implanted pellets showed increased corneal nerve regeneration after superficial injury compared with those receiving vehicle. VEGF injected subconjunctivally at the time of injury accelerated reinnervation, the recovery of mechanosensation, and epithelial wound healing. Endogenous VEGF expression was up-regulated in the corneal epithelium and stroma after wounding. Thus, VEGF can mediate peripheral neuron growth but requires the activation of multiple VEGF receptor types. In addition, VEGF can accelerate the return of sensory and trophic functions of damaged peripheral nerves. Wounding induces the expression of VEFG, which may modulate physiological nerve repair.—Pan, Z., Fukuoka, S., Karagianni, N., Guaiquil, V. H., Rosenblatt, M. I. Vascular endothelial growth factor promotes anatomical and functional recovery of injured peripheral nerves in the avascular cornea. PMID:23568776

Pan, Zan; Fukuoka, Shima; Karagianni, Natalia; Guaiquil, Victor H.; Rosenblatt, Mark I.

2013-01-01

126

Differentiation of peripheral nerve functions and properties with spectral analysis and Karnovsky-Roots staining: a preliminary study  

PubMed Central

Objective: The purpose of this study was to explore the possibility for analyzing and differentiating between motor and sensory functions of peripheral nerve axons using spectral technology. Methods: 10 ?m slide section of S1 anterior and posterior rabbit spinal nerve roots were made and then stained with Karnovsky-Roots method for molecular hyperspectral imaging microscopy analysis. In addition, Raman spectra data of nerve axons on each slide was collected after Karnovsky-Roots staining for 30 minutes. Results: Motor axons were differentiated from sensory axons in a nerve axon section hyperspectral image via Spectral angle mapper algorithm. Raman scatterings could be detected near 2110 cm-1, and 2155 cm-1 in motor axons after Karnvosky-Roots staining. The value of I2100/I1440 in motor axons are significantly different (P0.001) than in sensory axons after staining for 30 minutes. Conclusions: Motor and sensory nerve axons can be differentiated from their counterparts in 30 minutes by using Raman micro-spectroscopy analysis assisted with Karnovsky-Roots staining. PMID:25419356

Xu, Qintong; Chen, Zenggan; Li, Qiong; Liu, Haifei; Zhang, Jian; Yao, Wenhua; Zhang, Ren; Li, Qingli; Liu, Hongying; Zhang, Feng; Lineaweaver, William C

2014-01-01

127

Selective blockade of the dorsal scapular nerve for scapula surgery.  

PubMed

The dorsal scapular nerve, a proximal branch of the brachial plexus, may be imaged using ultrasound. This nerve supplies the rhomboid and levator scapulae muscles while providing significant sensory innervation to the scapula. An ultrasound-guided nerve block of the dorsal scapular nerve provided analgesia after surgery of the scapula. Selective blockade of this nerve, without blocking the remainder of the brachial plexus, results in specific analgesia of the scapula, sparing sensory and motor function of the ipsilateral arm. PMID:25439401

Auyong, David B; Cabbabe, Amy A

2014-12-01

128

Timeline: exorcizing the animal spirits: Jan Swammerdam on nerve function.  

PubMed

For more than 1,500 years, nerves were thought to function through the action of 'animal spirits'. In the seventeenth century, René Descartes conceived of these 'spirits' as liquids or gases, and used the idea to explain reflex action. But he was rapidly proven wrong by a young Dutchman, Jan Swammerdam. Swammerdam's elegant experiments pioneered the frog nerve muscle preparation and laid the foundation of our modern understanding of nerve function. PMID:11988778

Cobb, M

2002-05-01

129

Intraoperative Facial Nerve Monitoring in the Surgery of Cerebellopontine Angle Tumors: Improved Preservation of Nerve Function  

Microsoft Academic Search

The surgery of cerebellopontine angle tumors has shown remarkable progress over the last 20 years due to improved microsurgical techniques. However, the dissection of the facial nerve may lead to postoperative paresis as the result of the surgical trauma and the disruption of blood supply over a large distance. The functional status of the nerve can be intraoperatively monitored by

Thomas Lenarz; Arne Ernst

1994-01-01

130

A semi-automated analysis method of small sensory nerve fibers in human skin-biopsies.  

PubMed

Computerized detection method (CDM) software programs have been extensively developed in the field of astronomy to process and analyze images from nearby bright stars to tiny galaxies at the edge of the Universe. These object-recognition algorithms have potentially broader applications, including the detection and quantification of cutaneous small sensory nerve fibers (SSNFs) found in the dermal and epidermal layers, and in the intervening basement membrane of a skin punch biopsy. Here, we report the use of astronomical software adapted as a semi-automated method to perform density measurements of SSNFs in skin-biopsies imaged by Laser Scanning Confocal Microscopy (LSCM). In the first half of the paper, we present a detailed description of how the CDM is applied to analyze the images of skin punch biopsies. We compare the CDM results to the visual classification results in the second half of the paper. Abbreviations used in the paper, description of each astronomical tools, and their basic settings and how-tos are described in the appendices. Comparison between the normalized CDM and the visual classification results on identical images demonstrates that the two density measurements are comparable. The CDM therefore can be used - at a relatively low cost - as a quick (a few hours for entire processing of a single biopsy with 8-10 scans) and reliable (high-repeatability with minimum user-dependence) method to determine the densities of SSNFs. PMID:19852982

Tamura, Kazuyuki; Mager, Violet A; Burnett, Lindsey A; Olson, John H; Brower, Jeremy B; Casano, Ashley R; Baluch, Debra P; Targovnik, Jerome H; Windhorst, Rogier A; Herman, Richard M

2010-01-15

131

Phenotyping the function of TRPV1-expressing sensory neurons by targeted axonal silencing.  

PubMed

Specific somatosensations may be processed by different subsets of primary afferents. C-fibers expressing heat-sensitive TRPV1 channels are proposed, for example, to be heat but not mechanical pain detectors. To phenotype in rats the sensory function of TRPV1(+) afferents, we rapidly and selectively silenced only their activity, by introducing the membrane-impermeant sodium channel blocker QX-314 into these axons via the TRPV1 channel pore. Using tandem mass spectrometry we show that upon activation with capsaicin, QX-314 selectively accumulates in the cytosol only of TRPV1-expressing cells, and not in control cells. Exposure to QX-314 and capsaicin induces in small DRG neurons a robust sodium current block within 30 s. In sciatic nerves, application of extracellular QX-314 with capsaicin persistently reduces C-fiber but not A-fiber compound action potentials and this effect does not occur in TRPV1(-/-) mice. Behavioral phenotyping after selectively silencing TRPV1(+) sciatic nerve axons by perineural injections of QX-314 and capsaicin reveals deficits in heat and mechanical pressure but not pinprick or light touch perception. The response to intraplantar capsaicin is substantially reduced, as expected. During inflammation, silencing TRPV1(+) axons abolishes heat, mechanical, and cold hyperalgesia but tactile and cold allodynia remain following peripheral nerve injury. These results indicate that TRPV1-expressing sensory neurons process particular thermal and mechanical somatosensations, and that the sensory channels activated by mechanical and cold stimuli to produce pain in naive/inflamed rats differ from those in animals after peripheral nerve injury. PMID:23283344

Brenneis, Christian; Kistner, Katrin; Puopolo, Michelino; Segal, David; Roberson, David; Sisignano, Marco; Labocha, Sandra; Ferreirós, Nerea; Strominger, Amanda; Cobos, Enrique J; Ghasemlou, Nader; Geisslinger, Gerd; Reeh, Peter W; Bean, Bruce P; Woolf, Clifford J

2013-01-01

132

Exploring developmental, functional, and evolutionary aspects of amphioxus sensory cells  

PubMed Central

Amphioxus has neither elaborated brains nor definitive sensory organs, so that the two may have evolved in a mutually affecting manner and given rise to the forms seen in extant vertebrates. Clarifying the developmental and functional aspects of the amphioxus sensory system is thus pivotal for inferring the early evolution of vertebrates. Morphological studies have identified and classified amphioxus sensory cells; however, it is completely unknown whether the morphological classification makes sense in functional and evolutionary terms. Molecular markers, such as gene expression, are therefore indispensable for investigating the developmental and functional aspects of amphioxus sensory cells. This article reviews recent molecular studies on amphioxus sensory cells. Increasing evidence shows that the non-neural ectoderm of amphioxus can be subdivided into molecularly distinct subdomains by the combinatorial code of developmental cues involving the RA-dependent Hox code, suggesting that amphioxus epithelial sensory cells developed along positional information. This study focuses particularly on research involving the molecular phylogeny and expression of the seven-transmembrane, G protein-coupled receptor (GPCR) genes and discusses the usefulness of this information for characterizing the sensory cells of amphioxus. PMID:16763674

Satoh, Gouki

2006-01-01

133

Interaction between selective cyclooxygenase inhibitors and capsaicin-sensitive afferent sensory nerves in pathogenesis of stress-induced gastric lesions. Role of oxidative stress.  

PubMed

Gastric microcirculation plays an important role in the maintenance of the mucosal gastric integrity and the mechanism of injury as well as providing protection to the gastric mucosa. Disturbances in the blood perfusion, through the microcapillaries within the gastric mucosa may result in the formation of mucosal damage. Acute gastric mucosal lesions constitute an important clinical problem. Originally, one of the essential component of maintaining the gastric mucosal integrity was the biosynthesis of prostaglandins (PGs), an issue that has captured the attention of numerous investigations. PGs form due to the activity of cyclooxygenase (COX), an enzyme which is divided into 2 isoforms: constitutive (COX-1) and inducible (COX-2) ones. The inhibition of COX-1 by SC-560, or COX-2 by rofecoxib, reduces gastric blood flow (GBF) and impairs gastric mucosal integrity. Another detrimental effect on the gastric mucosal barrier results from the ablation of sensory afferent nerves by neurotoxic doses of capsaicin. Functional ablation of the sensory afferent nerves by capsaicin attenuates GBF and also renders the gastric mucosa more susceptible to gastric mucosal damage induced by ethanol, aspirin and stress. However, the role of reactive oxygen species (ROS) in the interaction between COX specific inhibitors and afferent sensory nerves has not been extensively studied. The aim of our present study was to determine the participation of ROS in pathogenesis of stress-induced gastric lesions in rats administered with SC-560 or rofecoxib, with or without ablation of the sensory afferent nerves. ROS were estimated by measuring the gastric mucosal tissue level of MDA and 4-HNE, the products of lipid peroxidation by ROS as well as the SOD activity and reduced glutathione (GSH) levels, both considered to be scavengers of ROS. It was demonstrated that exposure to 3.5 h of WRS resulted in gastric lesions, causing a significant increase of MDA and 4-HNE in the gastric mucosa, accompanied by a decrease of SOD activity and mucosal GSH level. Pretreatment with COX-1 and COX-2 inhibitors (SC-560 and rofecoxib, respectively) aggravated the number of gastric lesions, decreased GBF, attenuated GSH level without further significant changes in MDA and 4-HNE tissue levels and SOD activity. Furthermore, the capsaicin--nactivation of sensory nerves resulted in exaggeration of gastric mucosal damage induced by WRS and this was further augmented by rofecoxib. We conclude that oxidative stress, as reflected by an increase of MDA and 4-HNE tissue concentrations (an index of lipid peroxidation), as well as decrease of SOD activity and the fall in GSH tissue level, may play an important role in the mechanism of interaction between the inhibition of COX activity and afferent sensory nerves releasing vasoactive neuropeptides. This is supported by the fact that the addition of specific COX-1 or COX-2 inhibitors to animals with capsaicin denervation led to exacerbation of gastric lesions, and further fall in the antioxidizing status of gastric mucosa exposed to stress. PMID:22653901

Kwiecien, S; Konturek, P C; Sliwowski, Z; Mitis-Musiol, M; Pawlik, M W; Brzozowski, B; Jasnos, K; Magierowski, M; Konturek, S J; Brzozowski, T

2012-04-01

134

Histopathologic and functional effects of facial nerve following electrical stimulation  

Microsoft Academic Search

The aim of the study is to investigate the functional and histopathologic changes in facial nerve due to the application of\\u000a various violent and numerous electrical stimuli to the facial nerve. The study was carried out with Wistar rats weighing between\\u000a 200 and 300 g. The facial nerves of the subjects were located and stimulated with electrical stimulator. Then five groups

Emrah Sapmaz; Irfan Kaygusuz; Hayrettin Cengiz Alpay; Nusret Akpolat; Erol Keles; Turgut Karlidag; Israfil Orhan; Sinasi Yalcin

2010-01-01

135

Motor function recovery during peripheral nerve multiple regeneration.  

PubMed

Neuronal functional compensation and multiple regenerating axon sprouting occur during peripheral nerve regeneration. Sprouting nerve buds were quantitatively maintained and had matured when multiple injured distal nerves were anastomosed to smaller number of proximal nerve stumps; this has positive clinical significance for proximal stump damage. This study investigated whether sprouting axon buds would reinnervate the distal neuromuscular junction and maintain the function of the target organ under compensation conditions. The results showed that the sprouting axon buds maintained the numbers and morphology of motor end plates repaired by a smaller number of proximal nerve stumps, and recovered 80.0% tetanic muscle force compared with the normal side. Meanwhile, nerve conduction velocity, compound muscle action potential and diameter of muscular fibres declined 72.7%, 73.2% and 61.8%, respectively, compared with normal. This observation indicates the potential functional reserve of neurons and that it is feasible to repair nerve fibre injury through anastomosis of multiple distal nerve stumps with a smaller number of proximal nerve stumps, within the limits of compensation. Copyright © 2013 John Wiley & Sons, Ltd. PMID:24323657

An, Shuai; Zhang, Peixun; Peng, Jianping; Deng, Lei; Wang, Zhenwei; Wang, Zhiyong; Wang, Yanhua; Yin, Xiaofeng; Kou, Yuhui; Ha, Na; Jiang, Baoguo

2015-04-01

136

Effect of Remote Sensory Noise on Hand Function Post Stroke  

PubMed Central

Hand motor impairment persists after stroke. Sensory inputs may facilitate recovery of motor function. This pilot study tested the effectiveness of tactile sensory noise in improving hand motor function in chronic stroke survivors with tactile sensory deficits, using a repeated measures design. Sensory noise in the form of subthreshold, white noise, mechanical vibration was applied to the wrist skin during motor tasks. Hand dexterity assessed by the Nine Hole Peg Test and the Box and Block Test and pinch strength significantly improved when the sensory noise was turned on compared with when it was turned off in chronic stroke survivors. The subthreshold sensory noise to the wrist appears to induce improvements in hand motor function possibly via neuronal connections in the sensoriomotor cortex. The approach of applying concomitant, unperceivable mechanical vibration to the wrist during hand motor tasks is easily adoptable for clinic use as well as unsupervised home use. This pilot study suggests a potential for a wristband-type assistive device to complement hand rehabilitation for stroke survivors with sensorimotor deficit. PMID:25477806

Seo, Na Jin; Kosmopoulos, Marcella Lyn; Enders, Leah R.; Hur, Pilwon

2014-01-01

137

A comparison of nerve conduction velocities and current perception thresholds as correlates of clinical severity of diabetic sensory neuropathy.  

PubMed Central

Nerve conduction velocities (NCVs) are the standard measurements used to confirm the presence or absence of diabetic neuropathy. NCVs were contrasted with the newer technique of measurement of alternating current perception thresholds (CPTs) in assessing the quantitative level of correlation with severity of diabetic sensory neuropathy. A very detailed, scored neurological history (symptoms) and physical examination, emphasising sensory assessment, was conducted on 71 individuals with diabetic neuropathy of varying degrees of severity. Sensory and motor NCVs and CPTs at 5, 250, and 2000 Hz of the upper and lower extremities were determined for these individuals. In addition, vibration thresholds (VTs) were measured as a third modality. Twenty eight individuals underwent repeated evaluations at 2, 6, 10 and 12 months after the initial procedures. Using the results of 169 complete evaluations, correlations were determined between physical scores (PS) and symptoms scores (SS) and NCVs. NCV correlations with the SS were weaker than with the PS. The strongest of the correlations were found between the PS and motor NCVs of the median nerve (rho = 0.29) and the tibial nerve (rho = 0.38). Normal NCVs were present in the face of very significant historical and physical abnormality. Correlations of the SS and PS with both VTs and CPTs were higher than with the NCVs. CPTs proved the more effective as predictors of both symptomatic and physical impairment. NCVs appear to lack the resolving power necessary to evaluate subtle differences in clinical state of diabetic sensory neuropathy. The supplementary use of current perception testing may improve the quantitative assessment of this condition. PMID:2738593

Rendell, M S; Katims, J J; Richter, R; Rowland, F

1989-01-01

138

Edaravone promotes functional recovery after mechanical peripheral nerve injury  

PubMed Central

Edaravone has been shown to reduce ischemia/reperfusion-induced peripheral nerve injury. However, the therapeutic effect of edaravone on peripheral nerve injury caused by mechanical factors is unknown. In the present study, we established a peripheral nerve injury model by crushing the sciatic nerve using hemostatic forceps, and then administered edaravone 3 mg/kg intraperitoneally. The sciatic functional index and superoxide dismutase activity of the sciatic nerve were increased, and the malondialdehyde level was decreased in animals in the edaravone group compared with those in the model group. Bcl-2 expression was increased, but Bax expression was decreased in anterior horn cells of the L4-6 spinal cord segments. These results indicated that edaravone has a neuroprotective effect following peripheral nerve injury caused by mechanical factors through alleviating free radical damage to cells and inhibiting lipid peroxidation, as well as regulating apoptosis-related protein expression. PMID:25374594

Zhang, Teng; Li, Zhengwei; Dong, Jianli; Nan, Feng; Li, Tao; Yu, Qing

2014-01-01

139

Median-ulnar nerve communications: electrophysiological demonstration of motor and sensory fibre cross-over  

Microsoft Academic Search

In a 33-year-old female with carpal tunnel syndrome the presence of anomalous communications between median and ulnar nerves was electrophysiologically demonstrated in the forearm. Motor latencies from proximal and distal stimulation sites along the median nerve fibres to the abductor pollicis brevis were identical. Proximal latency “increased” after procaine infiltration of the ulnar nerve at the wrist. Normal latency to

L. Santoro; R. Rosato; G. Caruso

1983-01-01

140

Glycomimetic functionalized collagen hydrogels for peripheral nerve repair  

NASA Astrophysics Data System (ADS)

Despite the innate regenerative potential of the peripheral nervous system, functional recovery is often limited. The goal of this dissertation was to develop a clinically relevant biomaterial strategy to (1) encourage the regrowth of axons and (2) direct them down their appropriate motor tracts. To this end, we use peptide mimics of two glycans, polysialic acid (PSA) and an epitope first discovered on human natural killer cells (HNK-1), to functionalize type I collagen hydrogels. Previous studies have shown that these molecules, in their glycan and glycomimetic form, are associated with acceleration of neurite outgrowth, glial cell proliferation, and motoneuron targeting. In vitro, we demonstrated the retained functionality of the peptide glycomimetics after conjugation to a type I collagen backbone. While HNK-functionalized collagen increased motor neurite outgrowth, PSA-functionalized collagen encouraged motor and sensory neurite outgrowth and Schwann cell extension and proliferation. When we introduce these glycomimetic-functionalized collagen hydrogels into a critical gap femoral nerve model, we show that both PSA and HNK-functionalized hydrogels yielded a significant increase in functional recovery when compared to saline, native and scramble-coupled hydrogels. However, there was an interesting divergence in the morphological results: PSA-functionalized hydrogels increased axon count and HNK-functionalized hydrogels increased motoneuron targeting and myelination. We believed that these differences may be attributed to distinct mechanisms by which the glycomimetics impart their benefit. Interestingly, however, we found no synergistic gain in recovery with the use of our composite hydrogels which we speculated may be due to an inadequate dose of the individual glycomimetic. To address this possibility, we show that increasing the amount of functionalized peptide functionalized in our composite hydrogels led to increases in axon count and area of regeneration, but does not affect the degree of functional recovery. Finally, in order to assess potential mechanisms by which our glycomimetics impart benefit, we describe a novel platform for studying neural cell/biomaterial interaction through the use of two types of motoneuron cultures, dissociated spinal cord neurons and organotypic spinal cord slices. We show promising evidence that this strategy can be used to probe signaling pathways potentially involved in the action of these bioactives.

Masand, Shirley Narain

141

Peripheral nerve lengthening as a regenerative strategy  

PubMed Central

Peripheral nerve injury impairs motor, sensory, and autonomic function, incurring substantial financial costs and diminished quality of life. For large nerve gaps, proximal lesions, or chronic nerve injury, the prognosis for recovery is particularly poor, even with autografts, the current gold standard for treating small to moderate nerve gaps. In vivo elongation of intact proximal stumps towards the injured distal stumps of severed peripheral nerves may offer a promising new strategy to treat nerve injury. This review describes several nerve lengthening strategies, including a novel internal fixator device that enables rapid and distal reconnection of proximal and distal nerve stumps. PMID:25317163

Vaz, Kenneth M.; Brown, Justin M.; Shah, Sameer B.

2014-01-01

142

Technical Aspects of Intraoperative Monitoring of Lower Cranial Nerve Function  

PubMed Central

The efficacy of monitoring facial nerve activity in decreasing long-term morbidity has promoted an interest in monitoring other at-risk cranial nerves during procedures that involve manipulation of the basal cranial nerves. This presentation details practical techniques for monitoring the lower cranial nerves, which have been experientially developed over the past 9 years. Emphasis is placed on the selection of electrodes and procedural changes required for reliable and safe stimulation of the basal cranial nerves. Either paired hook-wire or tethered needle electrodes can be used for monitoring glossopharyageal, accessory, and hypoglossal nerve function. Several options for monitoring vagus nerve function are discussed. Of these, the transoral placement of paired hook-wire electrodes remains the most reliable, cost-effective, and least morbid technique. Electrical stimulation of the glossopharyngeal and vagus nerves carries the risk of unanticipated, potentially irreversible disturbances in cardiovascular function. Guidelines for type and optimal placement of stimulating electrodes and recommended intensity levels to prevent unfavorable reactions are presented. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:17170965

Mishler, E. Tracy; Smith, Peter G.

1995-01-01

143

[Peripheral nerve lesions of experimental leprosy in monkeys. V. Histopathological finding of cutaneous nerves and cutaneous sensory organs].  

PubMed

The skin samples of each palm side and dorsum side of finger, nose and peripheral nerves running under the finger skin at the area between proximal phalanx and distal phalanx of mangabey monkey A022 and rhesus monkey A125 were studied by histopathological methods (semithin section and light microscopic findings). Results found about this study were as follows. 1. In spite of the existence of a large amount of leprosy bacilli at the areas of corium and subcutis, some of Meissner's corpuscles, Vater-Pacinian corpuscles (or Golgi-Mazzoni's corpuscles) and Krauze's end bulbs-like structures were observed. 2. Occasionally, several intracytoplasmic foamy structures containing a large amount of leprosy bacilli were observed at the shallow and deep layers of stratum papillare of corium, where leprosy bacilli were not so remarkable as shown on Figure 4. So, it was thought that the affinity of leprosy bacilli to free nerve endings should be exist there. 3. Some of M. arrector pili were kept in good condition in spite of the existence of multiplying leprosy bacilli around the hair follicles. 4. It was thought that the histopathological findings of the fascicles of cutaneous nerves were classified to 4 patterns. The first pattern of histopathological finding of the cutaneous nerve was shown as A on Figure 25. In this pattern observed in almost of all the fascicles locating at the subcutis, no leprosy bacillus was observed inside the fascicles, and the nerve fibers were kept in good condition. The second pattern observed in almost of all the fascicles located at the corium, was shown as B on Figure 25. In this pattern, a large amount of leprosy bacilli were observed inside the fascicles, and the nerve fibers were often kept in good condition. The third pattern observed in almost of all the fascicles located at the deep layer of corium and subcutis, was shown as C on Figure 25. In this pattern, not only multiplying leprosy bacilli but also remarkable fibrosis were found inside one fascicle, and many nerve fibers disappeared by the existence of the bacilli and fibrosis. The final pattern observed in almost of all the fascicles located at the deep layer of corium and subcutis, was shown as D on Figure 25. In this pattern, remarkable fibrosis was observed inside the fascicles, and the nerve fibers often disappeared by the existence of fibrosis.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2697712

Fukunishi, Y

1989-01-01

144

Balance function and sensory integration after mild traumatic brain injury.  

PubMed

Abstract Objective: This study examined the disparities in balance functions and sensory integration in patients with mild traumatic brain injuries (mTBIs) and healthy controls. Participants: One hundred and seven patients with mTBI and 107 age- and sex-matched controls were recruaited for this study. Primary measures: Symptoms of dizziness, balance functions and the ability to perform daily activities were assessed using the dizziness handicap inventory (DHI). This study also performed the postural-stability test and a modified clinical test of sensory integration by using the Biodex Stability System (BBS). Results: DHI scores (functional, emotional, physical and total self-reported scores) were substantially increased in patients following an mTBI compared with the scores of the controls (p?sensory-integration test index (eyes-open-firm-surface index) (p?=?0.006) were substantially lower in patients with mTBI than in the controls. However, indices of two other postural-stability test indices (overall and medial-lateral) and three other sensory-integration tests indices (eyes-closed-firm-surface, eyes-open-foam-surface and eyes-closed-foam-surface) measured for the mTBI group did not differ from those of the control group. Conclusion: Activities of daily living, balance in postural stability and sensory integration were strongly impaired in patients with mTBI. PMID:25265292

Lin, Li-Fong; Liou, Tsan-Hon; Hu, Chaur-Jong; Ma, Hon-Ping; Ou, Ju-Chi; Chiang, Yung-Hsiao; Chiu, Wen-Ta; Tsai, Shin-Han; Chu, Woei-Chyn

2015-01-01

145

Evaluation of phrenic nerve and diaphragm function with peripheral nerve stimulation and M-mode ultrasonography in potential pediatric phrenic nerve or diaphragm pacing candidates.  

PubMed

Assessing phrenic nerve function in the setting of diaphragmatic paralysis in diaphragm pacing candidates can be challenging. Traditional imaging modalities and electrodiagnostic evaluations are technically difficult. Either modality alone is not a direct measure of the function of the phrenic nerve and diaphragm unit. In this article, the authors present their method for evaluating phrenic nerve function and the resulting diaphragm function. Stimulating the phrenic nerve with transcutaneous stimulation and directly observing the resulting movement of the hemidiaphragm with M-mode ultrasonography provides quantitative data for predicting the success of advancing technologies such as phrenic nerve pacing and diaphragm pacing. PMID:25479785

Skalsky, Andrew J; Lesser, Daniel J; McDonald, Craig M

2015-02-01

146

The method of isolation of the crayfish abdominal stretch receptor maintaining a connection of the sensory neuron to the ventral nerve cord ganglion.  

PubMed

The crayfish stretch receptor consisting of the single mechanoreceptor neurons enveloped by satellite glial cells is the simplest functioning neuroglial preparation. However, during isolation, its axons are usually transected that eliminates afferent regulation and induces complex axotomy-related signaling responses in neurons and satellite glia. We developed new microsurgical method of crayfish stretch receptor isolation, which preserves connections of sensory neurons to the ventral nerve cord ganglion. The stretch receptor may either remain on the abdominal carapace, or be completely isolated. In both cases, it may be either intact, or axotomized. The integrity of axons was confirmed by firing recording from proximal and distal axon points. Normal, necrotic and apoptotic cells were visualized using double fluorochroming with Hoechst 33342 and propidium iodide. The isolated mechanoreceptor neurons maintain regular firing during 8-10 or more hours. Glial cells surrounding non-axotomized neurons demonstrate lower necrosis and apoptosis levels than the axotomized ones. Unlike the existing method, in which the sensory neurons were axotomized, the present method preserves links between the sensory neurons and the ganglion and makes possible to avoid consequences of axotomy in neurons and satellite glia. The present neuroglial preparation may be used as a simple but informative model object in studies of axotomy-induced degeneration and survival of peripheral neurons, the role of glia in neuron injury, the signaling mechanisms of neuroglial interactions, and the effects of diverse physical and chemical factors on neuronal and glial cells. PMID:25374161

Khaitin, Andrej M; Rudkovskii, Mikhail V; Uzdensky, Anatoly B

2015-03-01

147

Selective decrease of small sensory neurons in lumbar dorsal root ganglia labeled with horseradish peroxidase after ND:YAG laser irradiation of the tibial nerve in the rat  

SciTech Connect

Recent electrophysiological evidence indicates that Q-switched Nd:YAG laser irradiation might have selective effects on neural impulse transmission in small slow conducting sensory nerve fibers as compared to large diameter afferents. In an attempt to clarify the ultimate fate of sensory neurons after laser application to their peripheral axons, we have used horseradish peroxidase (HRP) as a cell marker to retrogradely label sensory neurons innervating the distal hindlimb in the rat. Pulsed Nd:YAG laser light was applied to the tibial nerve at pulse energies of 70 or 80 mJ/pulse for 5 min in experimental rats. Seven days later HRP was applied to the left (laser-treated) and to the contralateral (untreated) tibial nerve proximal to the site of laser irradiation. In control animals the numbers of HRP-labeled dorsal root ganglion cells were not significantly different between the right and the left side. In contrast, after previous laser irradiation labeling was always less on the laser-treated side (2183 +/- 513 cells, mean +/- SEM) as compared to the untreated side (3937 +/- 225). Analysis of the dimensions of labeled cells suggested that the reduction of labeled cells on the laser-treated side was mainly due to a deficit in small sensory neurons. Since the conduction velocity of nerve fibers is related to the size of their somata, our histological data imply that laser light selectively affects retrograde transport mechanisms for HRP in slow conducting sensory nerve fibers.

Wesselmann, U.; Lin, S.F.; Rymer, W.Z. (Northwestern Univ. Medical School, Chicago, IL (USA))

1991-02-01

148

Electrophysiological aspects of sensory conduction velocity in healthy adults. 1. Conduction velocity from digit to palm, from palm to wrist, and across the elbow, as a function of age.  

PubMed Central

The sensory conduction velocity from digit to palm and from palm to wrist was determined in median (digit 3) and ulnar (digit 5) nerves in 47 healthy subjects with age range from 21 to 77 years. The decrement of the sensory conduction as a function of age was more marked in the palm to wrist than in the digit to palm segment. Sensory conduction velocity of the ulnar nerve across the elbow was also studied. Irregularities in the shape of the sensory evoked potential recorded above the cubital sulcus were found in 12.76% of cases, especially in subjects over 50 years of age. These results suggest that aging causes decrement in sensory conduction and changes in the shape of the evoked potentials, especially at points where the nerves are more frequently compressed. Images PMID:731254

Cruz Martínez, A; Barrio, M; Pérez Conde, M C; Gutiérrez, A M

1978-01-01

149

Roles of prostaglandins, nitric oxide and the capsaicin-sensitive sensory nerves in gastroprotection produced by ecabet sodium.  

PubMed

We determined the mechanism of the gastroprotective effects of ecabet sodium (ecabet), a new antiulcer drug. Ecabet (12.5-100 mg/kg p.o.) dose-dependently protected gastric mucosa from ethanol-induced injuries in rats, as determined with the use of both macroscopic and microscopic analyses. Both inhibition of prostaglandin (PG) formation by indomethacin (5 mg/kg s.c.) and functional ablation of capsaicin-sensitive sensory nerves (CPSN) by systemic administration of capsaicin (125 mg/kg s.c.) partly reduced the gastroprotective activity of ecabet (25 and 100 mg/kg p.o.). Ecabet increased rat gastric mucosal PGE2 formation. The treatment with indomethacin but not capsaicin decreased the ecabet-induced increase in PGE2 formation. Inhibition of nitric oxide (NO) formation by NG-monomethyl-L-arginine (L-NMMA; 100 mg/kg i.v.) partly reversed the gastroprotective effect of ecabet and completely reversed that of capsaicin at an oral dose of 0.5 mg/kg, respectively. The effect of L-NMMA was abolished by pretreatment with L-arginine (100 mg/kg i.v.) but not with D-arginine (100 mg/kg i.v.). The gastroprotective activity of ecabet (25 mg/kg p.o.) was fully reversed by pretreatment with indomethacin in combination with L-NMMA or CPSN ablation. On the contrary, a combination of L-NMMA and CPSN ablation did not have additional effect on the suppression by either treatment alone. These findings indicate that the gastroprotection by ecabet is cooperatively mediated by endogenous PGs and CPSN-related endogenous NO. PMID:7562591

Kinoshita, M; Kume, E; Tamaki, H

1995-10-01

150

Neuroselective Current Perception Threshold Evaluation of Bladder Mucosal Sensory Function  

Microsoft Academic Search

Objective: To evaluate human bladder mucosal sensory function by neuroselective Current Perception Threshold (CPT) measures from healthy and neuropathic bladders.Methods: Eight healthy volunteers and 38 patients with urinary symptoms underwent conventional urodynamic tests including water-filling cystometry and ice water test. Standardized neuroselective CPT measures were obtained from the left index finger and the mucosa of the posterior bladder wall. Three

Osamu Ukimura; So Ushijima; Hisashi Honjo; Tsuyoshi Iwata; Kei Suzuki; Naoki Hirahara; Koji Okihara; Yoichi Mizutani; Akihiro Kawauchi; Tsuneharu Miki

2004-01-01

151

From the Cover: Gangliosides are functional nerve cell ligands for myelin-associated glycoprotein (MAG), an inhibitor of nerve regeneration  

Microsoft Academic Search

Myelin-associated glycoprotein (MAG) binds to the nerve cell surface and inhibits nerve regeneration. The nerve cell surface ligand(s) for MAG are not established, although sialic acid-bearing glycans have been implicated. We identify the nerve cell surface gangliosides GD1a and GT1b as specific functional ligands for MAG-mediated inhibition of neurite outgrowth from primary rat cerebellar granule neurons. MAG-mediated neurite outgrowth inhibition

Alka A. Vyas; Himatkumar V. Patel; Susan E. Fromholt; Marija Heffer-Lauc; Kavita A. Vyas; Jiyoung Dang; Melitta Schachner; Ronald L. Schnaar

2002-01-01

152

Microelectronic neural bridging of toad nerves to restore leg function?  

PubMed Central

The present study used a microelectronic neural bridge comprised of electrode arrays for neural signal detection, functional electrical stimulation, and a microelectronic circuit including signal amplifying, processing, and functional electrical stimulation to bridge two separate nerves, and to restore the lost function of one nerve. The left leg of one spinal toad was subjected to external mechanical stimulation and functional electrical stimulation driving. The function of the left leg of one spinal toad was regenerated to the corresponding leg of another spinal toad using a microelectronic neural bridge. Oscilloscope tracings showed that the electromyographic signals from controlled spinal toads were generated by neural signals that controlled the spinal toad, and there was a delay between signals. This study demonstrates that microelectronic neural bridging can be used to restore neural function between different injured nerves. PMID:25206698

Shen, Xiaoyan; Wang, Zhigong; Lv, Xiaoying; Huang, Zonghao

2013-01-01

153

Parasympathetic Functions in Children with Sensory Processing Disorder  

PubMed Central

The overall goal of this study was to determine if parasympathetic nervous system (PsNS) activity is a significant biomarker of sensory processing difficulties in children. Several studies have demonstrated that PsNS activity is an important regulator of reactivity in children, and thus, it is of interest to study whether PsNS activity is related to sensory reactivity in children who have a type of condition associated with sensory processing disorders termed sensory modulation dysfunction (SMD). If so, this will have important implications for understanding the mechanisms underlying sensory processing problems of children and for developing intervention strategies to address them. The primary aims of this project were: (1) to evaluate PsNS activity in children with SMD compared to typically developing (TYP) children, and (2) to determine if PsNS activity is a significant predictor of sensory behaviors and adaptive functions among children with SMD. We examine PsNS activity during the Sensory Challenge Protocol; which includes baseline, the administration of eight sequential stimuli in five sensory domains, recovery, and also evaluate response to a prolonged auditory stimulus. As a secondary aim we examined whether subgroups of children with specific physiological and behavioral sensory reactivity profiles can be identified. Results indicate that as a total group the children with severe SMD demonstrated a trend for low baseline PsNS activity, compared to TYP children, suggesting this may be a biomarker for SMD. In addition, children with SMD as a total group demonstrated significantly poorer adaptive behavior in the communication and daily living subdomains and in the overall Adaptive Behavior Composite of the Vineland than TYP children. Using latent class analysis, the subjects were grouped by severity and the severe SMD group had significantly lower PsNS activity at baseline, tones and prolonged auditory. These results provide preliminary evidence that children who demonstrate severe SMD may have physiological activity that is different from children without SMD, and that these physiological and behavioral manifestations of SMD may affect a child's ability to engage in everyday social, communication, and daily living skills. PMID:20300470

Schaaf, Roseann C.; Benevides, Teal; Blanche, Erna Imperatore; Brett-Green, Barbara A.; Burke, Janice P.; Cohn, Ellen S.; Koomar, Jane; Lane, Shelly J.; Miller, Lucy Jane; May-Benson, Teresa A.; Parham, Diane; Reynolds, Stacey; Schoen, Sarah A.

2009-01-01

154

Sympathetic skin response in acute sensory ataxic neuropathy  

Microsoft Academic Search

Sympathetic skin response (SSR) is a recently described objective method of studying sudomotor sympathetic nerve function and has been studied in a variety of peripheral neuropathies. We report SSR changes in nine patients with acute sensory ataxic neuropathy (ASAN). All had severe sensory and mild motor nerve conduction abnormalities; five had dysautonomia. SSR, elicited by electric shock and cough stimuli,

G. R. Arunodaya; A. B. Taly; H. S. Swamy

1995-01-01

155

Putative neurotrophic factors and functional recovery from peripheral nerve damage in the rat.  

PubMed Central

1. In rats, recovery of sensory-motor function following a crush lesion of the sciatic or tibial nerve was monitored by measuring foot reflex withdrawal from a local noxious stimulation of the foot sole. 2. Putative neurotrophic compounds were tested on this functional recovery model: melanocortins (peptides derived from ACTH (corticotropin) and alpha-MSH (melanotropin], gangliosides and nimodipine were effective whereas isaxonine and TRH (thyrotropin releasing hormone) were not. 3. Structure-activity studies with melanocortins revealed a similar effectiveness of alpha-MSH, [N-Leu4, D-Phe7]-alpha-MSH, desacetyl-alpha-MSH and the ACTH analogue ORG 2766, questioning the validity of the previously suggested notion that the melanotrophic properties of these peptides are responsible for their neurotrophic effect. 4. As recovery of function after peripheral nerve damage follows a similar time course in hypophysectomized (five days post operation) and sham-operated rats, effective melanocortin therapy does not mimic an endogenous peptide signal in the repair process from pituitary origin. 5. Subcutaneous treatment with ORG 2766 (7.5 micrograms kg-1 48 h-1) facilitates recovery of function following peripheral nerve damage in young (6-7 weeks old), mature (5 month old) and old (20 month old) rats. 6. In view of the diversity in structure of the effective neurotrophic factors and the complexity of nerve repair, the present data support the notion that peripheral nerve repair may be facilitated by different humoral factors likely to be active on different aspects of the recovery process. PMID:1678980

Van der Zee, C. E.; Brakkee, J. H.; Gispen, W. H.

1991-01-01

156

Comparison of second lumbrical and interosseus latencies with standard measures of median nerve function across the carpal tunnel: a prospective study of 450 hands  

Microsoft Academic Search

The second lumbrical-interosseus distal motor latency (2LI-DML) was compared prospectively in 450 hands. Median nerve function\\u000a was assessed by standard motor and sensory electrophysiological tests. In a control group of 100 hands the upper limit of\\u000a normal for the 2LI-DML was 0.5 ms. In all hands studied the correlation coefficients of 2LI-DML were higher with sensory nerve\\u000a tests than with

Wolfgang N. Löscher; Michaela Auer-Grumbach; Eugen Trinka; Gunther Ladurner; Hans-Peter Hartung

2000-01-01

157

Nerve growth factor/p75 neurotrophin receptor–mediated sensitization of rat sensory neurons depends on membrane cholesterol  

PubMed Central

Nerve growth factor (NGF) is an important mediator in the initiation of the inflammatory response and NGF via activation of the p75 neurotrophin receptor (p75NTR) and downstream sphingomyelin signaling leads to significant enhancement of the excitability of small diameter sensory neurons. Because of the interaction between sphingomyelin and cholesterol in creating membrane liquid-ordered domains known as membrane or lipid rafts, we examined whether neuronal NGF-induced sensitization via p75NTR was dependent on the integrity of membrane rafts. Here, we demonstrate that the capacity of NGF to enhance the excitability of sensory neurons may result from the interaction of p75NTR with its downstream signaling partner(s) in membrane rafts. Two agents known to disrupt membrane rafts, edelfosine and methyl-?-cyclodextrin (M?CD), block the increase in excitability produced by NGF. In contrast, treatment with M?CD containing saturated amounts of cholesterol does not alter the capacity of NGF to augment excitability. In addition, adding back M?CD with cholesterol restored the NGF-induced sensitization in previously cholesterol-depleted neurons, suggesting that cholesterol and the structural integrity of rafts are key in promoting NGF-mediated sensitization. Using established protocols to isolate detergent-resistant membranes, both p75NTR and the neuronal membrane raft marker, flotillin, localize to raft fractions. These results suggest that downstream signaling partners interacting with p75NTR in sensory neurons are associated with membrane raft signaling platforms. PMID:23811397

Zhang, Y.H.; Khanna, R.; Nicol, G.D.

2013-01-01

158

Intracerebroventricular Administration of Nerve Growth Factor Induces Gliogenesis in Sensory Ganglia, Dorsal Root, and within the Dorsal Root Entry Zone  

PubMed Central

Previous studies indicated that intracerebroventricular administration of nerve growth factor (NGF) leads to massive Schwann cell hyperplasia surrounding the medulla oblongata and spinal cord. This study was designed to characterize the proliferation of peripheral glial cells, that is, Schwann and satellite cells, in the trigeminal ganglia and dorsal root ganglia (DRG) of adult rats during two weeks of NGF infusion using bromodeoxyuridine (BrdU) to label dividing cells. The trigeminal ganglia as well as the cervical and lumbar DRG were analyzed. Along the entire neuraxis a small number of dividing cells were observed within these regions under physiological condition. NGF infusion has dramatically increased the generation of new cells in the neuronal soma and axonal compartments of sensory ganglia and along the dorsal root and the dorsal root entry zone. Quantification of BrdU positive cells within sensory ganglia revealed a 2.3- to 3-fold increase in glial cells compared to controls with a similar response to NGF for the different peripheral ganglia examined. Immunofluorescent labeling with S100? revealed that Schwann and satellite cells underwent mitosis after NGF administration. These data indicate that intracerebroventricular NGF infusion significantly induces gliogenesis in trigeminal ganglia and the spinal sensory ganglia and along the dorsal root entry zone as well as the dorsal root. PMID:24738070

Schlachetzki, Johannes C. M.; Pizzo, Donald P.; Morrissette, Debbi A.; Winkler, Jürgen

2014-01-01

159

Sensory integration functions of children with cochlear implants.  

PubMed

OBJECTIVE. We investigated sensory integration (SI) function in children with cochlear implants (CIs). METHOD. We analyzed deidentified records from 49 children ages 7 mo to 83 mo with CIs. Records included Sensory Integration and Praxis Tests (SIPT), Sensory Processing Measure (SPM), Sensory Profile (SP), Developmental Profile 3 (DP-3), and Peabody Developmental Motor Scales (PDMS), with scores depending on participants' ages. We compared scores with normative population mean scores and with previously identified patterns of SI dysfunction. RESULTS. One-sample t tests revealed significant differences between children with CIs and the normative population on the majority of the SIPT items associated with the vestibular and proprioceptive bilateral integration and sequencing (VPBIS) pattern. Available scores for children with CIs on the SPM, SP, DP-3, and PDMS indicated generally typical ratings. CONCLUSION. SIPT scores in a sample of children with CIs reflected the VPBIS pattern of SI dysfunction, demonstrating the need for further examination of SI functions in children with CIs during occupational therapy assessment and intervention planning. PMID:25184469

Koester, AnjaLi Carrasco; Mailloux, Zoe; Coleman, Gina Geppert; Mori, Annie Baltazar; Paul, Steven M; Blanche, Erna; Muhs, Jill A; Lim, Deborah; Cermak, Sharon A

2014-01-01

160

TRPM8 on mucosal sensory nerves regulates colitogenic responses by innate immune cells via CGRP.  

PubMed

TRPM8 is the molecular sensor for cold; however, the physiological role of TRPM8+ neurons at mucosal surfaces is unclear. Here we evaluated the distribution and peptidergic properties of TRPM8+ fibers in naive and inflamed colons, as well as their role in mucosal inflammation. We found that Trpm8(-/-) mice were hypersusceptible to dextran sodium sulfate (DSS)-induced colitis, and that Trpm8(-/-) CD11c+ DCs (dendritic cells) showed hyperinflammatory responses to toll-like receptor (TLR) stimulation. This was phenocopied in calcitonin gene-related peptide (CGRP) receptor-deficient mice, but not in substance P receptor-deficient mice, suggesting a functional link between TRPM8 and CGRP. The DSS phenotype of CGRP receptor-deficient mice could be adoptively transferred to wild-type (WT) mice, suggesting that CGRP suppresses the colitogenic activity of bone marrow-derived cells. TRPM8+ mucosal fibers expressed CGRP in human and mouse colon. Furthermore, neuronal CGRP contents were increased in colons from naive and DSS-treated Trpm8(-/-) mice, suggesting deficient CGRP release in the absence of TRPM8 triggering. Finally, treatment of Trpm8(-/-) mice with CGRP reversed their hyperinflammatory phenotype. These results suggest that TRPM8 signaling in mucosal sensory neurons is indispensable for the regulation of innate inflammatory responses via the neuropeptide CGRP.Mucosal Immunology advance online publication, 1 October 2014; doi:10.1038/mi.2014.82. PMID:25269705

de Jong, P R; Takahashi, N; Peiris, M; Bertin, S; Lee, J; Gareau, M G; Paniagua, A; Harris, A R; Herdman, D S; Corr, M; Blackshaw, L A; Raz, E

2014-10-01

161

Olfactory Cilia: Linking Sensory Cilia Function and Human Disease  

PubMed Central

The olfactory system gives us an awareness of our immediate environment by allowing us to detect airborne stimuli. The components necessary for detection of these odorants are compartmentalized in the cilia of olfactory sensory neurons. Cilia are microtubule-based organelles, which can be found projecting from the surface of almost any mammalian cell, and are critical for proper olfactory function. Mislocalization of ciliary proteins and/or the loss of cilia cause impaired olfactory function, which is now recognized as a clinical manifestation of a broad class of human diseases, termed ciliopathies. Future work investigating the mechanisms of olfactory cilia function will provide us important new information regarding the pathogenesis of human sensory perception diseases. PMID:19406873

Jenkins, Paul M.; McEwen, Dyke P.

2009-01-01

162

Mesenchymal stem cells and their secretome partially restore nerve and urethral function in a dual muscle and nerve injury stress urinary incontinence model.  

PubMed

Childbirth injures muscles and nerves responsible for urinary continence. Mesenchymal stem cells (MSCs) or their secretome given systemically could provide therapeutic benefit for this complex multisite injury. We investigated whether MSCs or their secretome, as collected from cell culture, facilitate recovery from simulated childbirth injury. Age-matched female Sprague-Dawley rats received pudendal nerve crush and vaginal distension (PNC+VD) and a single intravenous (iv) injection of 2 million MSCs or saline. Controls received sham injury and iv saline. Additional rats received PNC+VD and a single intraperitoneal (ip) injection of concentrated media conditioned by MSCs (CCM) or concentrated control media (CM). Controls received a sham injury and ip CM. Urethral and nerve function were assessed with leak point pressure (LPP) and pudendal nerve sensory branch potential (PNSBP) recordings 3 wk after injury. Urethral and pudendal nerve anatomy were assessed qualitatively by blinded investigators. Quantitative data were analyzed using one-way ANOVA and Holm-Sidak post hoc tests with P < 0.05 indicating significant differences. Both LPP and PNSBP were significantly decreased 3 wk after PNC+VD with saline or CM compared with sham-injured rats, but not with MSC or CCM. Elastic fiber density in the urethra increased and changed in orientation after PNC+VD, with a greater increase in elastic fibers with MSC or CCM. Pudendal nerve fascicles were less dense and irregularly shaped after PNC+VD and had reduced pathology with MSC or CCM. MSC and CCM provide similar protective effects after PNC+VD, suggesting that MSCs act via their secretions in this dual muscle and nerve injury. PMID:25377914

Deng, Kangli; Lin, Dan Li; Hanzlicek, Brett; Balog, Brian; Penn, Marc S; Kiedrowski, Matthew J; Hu, Zhiquan; Ye, Zhangqun; Zhu, Hui; Damaser, Margot S

2015-01-15

163

The effect of glycomimetic functionalized collagen on peripheral nerve repair  

PubMed Central

Increasing evidence suggests that the improper synaptic reconnection of regenerating axons is a significant cause of incomplete functional recovery following peripheral nerve injury. In this study, we evaluate the use of collagen hydrogels functionalized with two peptide glycomimetics of naturally occurring carbohydrates—polysialic acid (PSA) and human natural killer cell epitope epitope (HNK-1)—that have been independently shown to encourage nerve regeneration and axonal targeting. Our novel biomaterial was used to bridge a critical gap size (5 mm) in a mouse femoral nerve injury model. Functional recovery was assessed using gait and hind limb extension, and was significantly better in all glycomimetic peptide-coupled collagen conditions versus non-functional scrambled peptide-coupled collagen, native collagen, and saline controls. Analysis of cross-sections of the regenerated nerve demonstrated that hydrogels coupled with the PSA glycomimetic, but not HNK, had significant increases in the number of myelinated axons over controls. Conversely, hydrogels coupled with HNK, but not PSA, showed improvement in myelination. Additionally, significantly more correctly projecting motoneurons were observed in groups containing coupled HNK-1 mimicking peptide, but not PSA mimicking peptide. Given the distinct morphological outcomes between the two glycomimetics, our study indicates that the enhancement of recovery following peripheral nerve injury induced by PSA- and HNK-functionalized collagen hydrogels likely occurs through distinct mechanisms. PMID:22917737

Masand, Shirley N.; Chen, Jian; Perron, Isaac J.; Hammerling, Babette C.; Loers, Gabriele; Schachner, Melitta; Shreiber, David I.

2012-01-01

164

Reciprocal sympatho-sensory control: functional role of nucleotides and calcitonin gene-related peptide in a peripheral neuroeffector junction.  

PubMed

The rat vas deferens has scattered sensory afferens plus a dense network of sympathetic motor efferens; these fibers are not known to interact functionally. We ascertained whether sensory fibers modulate the release of sympathetic transmitters through the release of calcitonin gene-related peptide (CGRP) and reciprocally assessed whether sympathetic transmitters modulate the overflow of ir-CGRP from sensory fibers. The tissue overflow of electrically evoked sympathetic co-transmitters (ATP/metabolites, noradrenaline (NA), and immunoreactive neuropeptide tyrosine (ir-NPY)) and the motor responses elicited were quantified following either exogenous CGRP or capsaicin application to elicit peptide release. Conversely, the outflow of ir-CGRP was examined in the presence of sympathetic transmitters. Exogenous CGRP reduced in a concentration-dependent manner the electrically evoked outflow of ATP/metabolites, NA, and ir-NPY with EC(50) values of 1.3, 0.18, and 1.9 nM, respectively. CGRP also reduced the basal NA overflow. The CGRP-evoked modulation was blocked by CGRP8-37 or H-89. Release of endogenous CGRP by capsaicin significantly reduced the basal overflow of NA, ir-NPY, and the electrically evoked sympathetic transmitter release. ADP, 2-methylthioadenosine-5'-O-diphosphate (2-MeSADP), or UTP decreased the electrically evoked ir-CGRP overflow, whereas clonidine, ?,?-methyleneadenosine 5'-triphosphate (?,?-mATP), or adenosine (ADO) were inactive. CGRP acting postjunctionally also reduced the motor responses elicited by exogenous NA, ATP, or electrically evoked contractions. We conclude that CGRP exerts a presynaptic modulator role on sympathetic nerve endings and reciprocally ATP or related nucleotides influence the release of ir-CGRP from sensory fibers, highlighting a dynamic sympatho-sensory control between sensory fibers and sympathetic nerve ending. Postjunctional CGRP receptors further contribute to reduce the tissue sympathetic motor tone implying a pre and postjunctional role of CGRP as a sympathetic tone modulator. PMID:22178987

Donoso, M V; Hermosilla, D; Navarrete, C; Álvarez, P; Lillo, J G; Huidobro-Toro, J P

2012-02-17

165

Peripheral nerve stimulation in neurological rehabilitation  

Microsoft Academic Search

An injury to the central nervous system can result in a permanent loss of the voluntary motor function and sensation. However, the peripheral motor and sensory nerves below the level of lesion often remain intact, and so do the muscles. Functional Electrical Stimulation (FES) is a technique to restore motor and sensory functions after such injuries. The forces generated in

T. Sinkjaer; D. Popovic

2003-01-01

166

Thermographic evaluation of hind paw skin temperature and functional recovery of locomotion after sciatic nerve crush in rats  

PubMed Central

INTRODUCTION: Peripheral nerves are often damaged by direct mechanical injury, diseases, and tumors. The peripheral nerve injuries that result from these conditions can lead to a partial or complete loss of motor, sensory, and autonomic functions, which in turn are related to changes in skin temperature, in the involved segments of the body. The aim of this study was to evaluate the changes in hind paw skin temperature after sciatic nerve crush in rats in an attempt to determine whether changes in skin temperature correlate with the functional recovery of locomotion. METHODS: Wistar rats were divided into three groups: control (n?=?7), sham (n?=?25), and crush (n?=?25). All groups were subjected to thermographic, functional, and histological assessments. RESULTS: ?T in the crush group was different from the control and sham groups at the 1st, 3rd and 7rd postoperative days (p<0.05). The functional recovery from the crush group returned to normal values between the 3rd and 4th week post-injury, and morphological analysis of the nerve revealed incomplete regeneration at the 4th week after injury. DISCUSSION: This study is the first demonstration that sciatic nerve crush in rats induces an increase in hind paw skin temperature and that skin temperature changes do not correlate closely with functional recovery PMID:21876984

Z. Sacharuk, Viviane; A. Lovatel, Gisele; Ilha, Jocemar; Marcuzzo, Simone; Severo do Pinho, Alexandre; L. Xavier, Léder; A. Zaro, Milton; Achaval, Matilde

2011-01-01

167

A new paradigm of electrical stimulation to enhance sensory neural function.  

PubMed

The ability to improve peripheral neural transmission would have significant therapeutic potential in medicine. A technology of this kind could be used to restore and/or enhance sensory function in individuals with depressed sensory function, such as older adults or patients with peripheral neuropathies. The goal of this study was to investigate if a new paradigm of subsensory electrical noise stimulation enhances somatosensory function. Vibration (50Hz) was applied with a Neurothesiometer to the plantar aspect of the foot in the presence or absence of subsensory electrical noise (1/f type). The noise was applied at a proximal site, on a defined region of the tibial nerve path above the ankle. Vibration perception thresholds (VPT) of younger adults were measured in control and experimental conditions, in the absence or presence of noise respectively. An improvement of ?16% in VPT was found in the presence of noise. These are the first data to demonstrate that modulation of axonal transmission with externally applied electrical noise improves perception of tactile stimuli in humans. PMID:24894033

Breen, Paul P; ÓLaighin, Gearóid; McIntosh, Caroline; Dinneen, Sean F; Quinlan, Leo R; Serrador, Jorge M

2014-08-01

168

Chronic intraneural electrical stimulation for prosthetic sensory feedback  

Microsoft Academic Search

The functionality of prosthetic limbs is restricted by the limited availability of sensory feedback. The goal of the present research is the development of a multichannel microelectrode array for the presentation of sensory information directly to the sensory afferent neurons of the transected peripheral nerve of an amputee. Intraneural electrode arrays were developed and implanted in the proximal stump of

Daniel J. DiLorenzo; David J. Edell; Mark J. Koris; Ron R. Riso

2003-01-01

169

Impact of carpal tunnel surgery according to pre-operative abnormality of sensory conduction in median nerve: a longitudinal study  

PubMed Central

Background We have previously proposed that sensory nerve conduction (SNC) in the median nerve should be classed as abnormal when the difference between conduction velocities in the little and index fingers is > 8 m/s. In a prospective longitudinal study, we investigated whether this case definition distinguished patients who were more likely to benefit from surgical treatment. Methods We followed up 394 patients (response rate 56%), who were investigated by a neurophysiology service for suspected carpal tunnel syndrome. Information about symptoms, treatment and other possible determinants of outcome was obtained through questionnaires at baseline and after follow-up for a mean of 19.2 months. Analysis focused on 656 hands with numbness, tingling or pain at baseline. Associations of surgical treatment with resolution of symptoms were assessed by Poisson regression, and summarised by prevalence rate ratios (PRRs) and associated 95% confidence intervals (95% CIs). Results During follow-up, 154 hands (23%) were treated surgically, and sensory symptoms resolved in 241 hands (37%). In hands with abnormal median SNC, surgery was associated with resolution of numbness, tingling and pain (PRR 1.5, 95% CI 1.0-2.2), and of numbness and tingling specifically (PRR 1.8, 95% CI 1.3-2.6). In contrast, no association was apparent for either outcome when median SNC was classed as normal. Conclusions Our definition of abnormal median SNC distinguished a subset of patients who appeared to benefit from surgical treatment. This predictive capacity gives further support to its validity as a diagnostic criterion in epidemiological research. PMID:23947746

2013-01-01

170

Tiotropium modulates transient receptor potential V1 (TRPV1) in airway sensory nerves: A beneficial off-target effect???  

PubMed Central

Background Recent studies have suggested that the long-acting muscarinic receptor antagonist tiotropium, a drug widely prescribed for its bronchodilator activity in patients with chronic obstructive pulmonary disease and asthma, improves symptoms and attenuates cough in preclinical and clinical tussive agent challenge studies. The mechanism by which tiotropium modifies tussive responses is not clear, but an inhibition of vagal tone and a consequent reduction in mucus production from submucosal glands and bronchodilation have been proposed. Objective The aim of this study was to investigate whether tiotropium can directly modulate airway sensory nerve activity and thereby the cough reflex. Methods We used a conscious cough model in guinea pigs, isolated vagal sensory nerve and isolated airway neuron tissue– and cell-based assays, and in vivo single-fiber recording electrophysiologic techniques. Results Inhaled tiotropium blocked cough and single C-fiber firing in the guinea pig to the transient receptor potential (TRP) V1 agonist capsaicin, a clinically relevant tussive stimulant. Tiotropium and ipratropium, a structurally similar muscarinic antagonist, inhibited capsaicin responses in isolated guinea pig vagal tissue, but glycopyrrolate and atropine did not. Tiotropium failed to modulate other TRP channel–mediated responses. Complementary data were generated in airway-specific primary ganglion neurons, demonstrating that tiotropium inhibited capsaicin-induced, but not TRPA1-induced, calcium movement and voltage changes. Conclusion For the first time, we have shown that tiotropium inhibits neuronal TRPV1-mediated effects through a mechanism unrelated to its anticholinergic activity. We speculate that some of the clinical benefit associated with taking tiotropium (eg, in symptom control) could be explained through this proposed mechanism of action. PMID:24506933

Birrell, Mark A.; Bonvini, Sara J.; Dubuis, Eric; Maher, Sarah A.; Wortley, Michael A.; Grace, Megan S.; Raemdonck, Kristof; Adcock, John J.; Belvisi, Maria G.

2014-01-01

171

Sensory impairment of the lingual and inferior alveolar nerves following removal of impacted mandibular third molars  

Microsoft Academic Search

Abstract.In a prospective study 1106 impacted mandibular third molars were removed from 687 patients. Clinical, radiographic, and surgical factors were recorded. Postoperatively, we examined the modalities of common sensation in order to assess sensory deficit. The patients were followed up, until complete restitution occurred, or, if the sensibility failed to recover, for at least 6 months. A total of 3.6%

D. Gülicher; K. L. Gerlach

2001-01-01

172

Phoneutria nigriventer spider venom induces oedema in rat skin by activation of capsaicin sensitive sensory nerves  

Microsoft Academic Search

Phoneeutria nigriventer venom induces oedema formation when injected in the rat dorsal skin and such oedema is, in part, dependent on the stimulation of tachykinin NK1 receptors. This study investigated whether Phoneutria nigriventer venom acts directly on tachykinin NK1 receptors, or indirectly to activate sensory neurones which in turn release a tachykinin NK1 receptor agonist. The plasma extravasation induced by

Soraia K. P Costa; Gilberto de Nucci; Edson Antunes; Susan D Brain

1997-01-01

173

Modified Quad surgery significantly improves the median nerve conduction and functional outcomes in obstetric brachial plexus nerve injury  

PubMed Central

Background Nerve conduction studies or somatosensory evoked potentials (SSEPs) have become an important tool in the investigation of peripheral nerve lesions, and is sensitive in detecting brachial plexus nerve injury, and other nerve injuries. To investigate whether the modified Quad surgical procedure improves nerve conductivity and functional outcomes in obstetric brachial plexus nerve injury (OBPI) patients. Methods All nerves were tested with direct functional electrical stimulation. A Prass probe was used to stimulate the nerves, and recording the response, the compound motor action potential (CMAP) in the muscle. SSEP monitoring was performed pre- and post modified Quad surgery, stimulating the median and ulnar nerves at the wrist, the radial nerve over the dorsum of the hand, recording the peripheral, cervical and cortical responses. All patients have had the modified Quad surgery (n?=?19). The modified Quad surgery is a muscle release and transfer surgery with nerve decompressions. All patients were assessed preoperatively and postoperatively by evaluating video recordings of standardized movements, the modified Mallet scale to index active shoulder movements. Results The cervical responses were significantly lower in amplitude in the affected arm than the un-affected arm. The median nerve conduction was significantly improved from 8.04 to 9.26 (P?nerve conduction, and shoulder abduction were significantly improved in OBPI children, who have undergone the modified Quad procedure with neuroplasty, internal microneurolysis and tetanic stimulation of the median nerve. PMID:23714699

2013-01-01

174

[Clinical diagnosis of the olfactory nerve transport function].  

PubMed

Nasal administration of macromolecular drugs (peptides, nanoparticles) has a possibility to enable a drug delivery system beyond the blood brain barrier via olfactory nerve transport. Basic research on nasal drug delivery to the brain has been well studied. However, evaluation of the olfactory nerve transport function in patients with olfactory disorders has yet to be done, although such an evaluation is important in selecting candidates for clinical trials. Current olfactory function tests are useful for the analysis of olfactory thresholds in olfaction-impaired patients. However, the usefulness of using the increase in olfactory thresholds in patients as an index for evaluating olfactory nerve damage has not been confirmed because of the difficulty in directly evaluating the viability of the peripheral olfactory nerves. Nasally administered thallium-201 migrates to the olfactory bulb, as has been shown in healthy volunteers. Furthermore, transection of olfactory nerve fibers in mice significantly decreases migration of nasally administered thallium-201 to the olfactory bulb. The migration of thallium-201 to the olfactory bulb is reduced in patients with impaired olfaction due to head trauma, upper respiratory tract infections, and chronic rhinosinusitis, relative to the values in healthy volunteers. Nasally administrating thallium-201 followed by single photon emission computed tomography, X-ray computed tomography and magnetic resonance imaging might be useful in choosing candidates for clinical trials of nasal drug delivery methods to the brain. PMID:23123717

Shiga, Hideaki; Yamamoto, Junpei; Miwa, Takaki

2012-01-01

175

Influence of antagonist sensory and sympathetic nerves on smooth muscle cell differentiation in hypercholesterolemic rat.  

PubMed

The effect of sympathectomy and sensory denervation on vascular smooth muscle cell (SMC) differentiation was investigated in hypercholesterolemic rats. Newborn rats received injections of guanethidine, capsaicin or both for denervations. Shams received injections of vehicles. The four groups were fed 1% cholesterol diet for 3 months. Intact normocholesterolemic rats were also exploited. Serum total cholesterol and systolic blood pressure (SBP) were measured. Lipid presence in the arterial wall was shown by Red-Oil-O staining. Catecholamine- and CGRP-containing fibres, vimentin and the adult SMC markers alpha-SMC-actin, desmin and h-caldesmon were analysed in abdominal aorta by western blot and confocal microscope. The sympathetic (catecholamine) fibres and SBP increased after sensory denervation while the sensory (CGRP) fibres increased and SBP decreased after sympathectomy. SBP was not changed after double denervation. Total cholesterol increased in sham and rose further after sympathectomy. Vimentin and the three adult SMC markers were not influenced by hypercholesterolemia. However, in the sympathectomized aorta, vimentin increased, desmin did not change, whereas alpha-SMC-actin and h-caldesmon decreased. In the sensory-denervated aorta, vimentin decreased, desmin increased, alpha-SMC-actin did not change and h-caldesmon decreased but less than in sympathectomized aorta. In the doubly denervated aorta, vimentin did not change and the three adult SMC markers decreased, although less than in sympathectomized aorta for alpha-SMC-actin and h-caldesmon. Thickened intima was identified by Red-Oil-O staining in the sympathectomized and (less remarkably) doubly denervated aortas containing SMCs not fully dedifferentiated. Our findings suggest that sympathectomy induces intimal thickening and favours SMC dedifferentiation, whereas sensory denervation favours SMC differentiation. PMID:20181536

Hachani, Rafik; Dab, Houcine; Sakly, Mohsen; Vicaut, Eric; Callebert, Jacques; Sercombe, Richard; Kacem, Kamel

2010-06-24

176

The Association between Sensory Impairment and Functional Limitations in Balance in Community-Dwelling Older Adults  

E-print Network

for falls. The Fullerton Advanced Balance (FAB) Scale is a functional limitation test that measures multipleThe Association between Sensory Impairment and Functional Limitations in Balance in Community contribute to the ability to control balance (e.g.,peripheral sensory, central sensory processing

de Lijser, Peter

177

Semantic Relevance, Domain Specificity and the Sensory/Functional Theory of Category-Specificity  

ERIC Educational Resources Information Center

According to the sensory/functional theory of semantic memory, Living items rely more on Sensory knowledge than Non-living ones. The sensory/functional explanation of category-specificity assumes that semantic features are organised on the basis of their content. We report here a study on DAT patients with impaired performance on Living items and…

Sartori, Giuseppe; Gnoato, Francesca; Mariani, Ilenia; Prioni, Sara; Lombardi, Luigi

2007-01-01

178

Hyperalgesia and functional sensory loss in restless legs syndrome.  

PubMed

Pain and other sensory signs in patients with restless legs syndrome (RLS) are still poorly understood, as most investigations focus on motor system dysfunctions. This study aimed to investigate somatosensory changes in patients with primary RLS and the restoration of somatosensory function by guideline-based treatment. Forty previously untreated RLS patients were investigated unilaterally over hand and foot using quantitative sensory testing (QST) and were compared with 40 age- and gender-matched healthy subjects. The predominant finding in RLS patients was 3- to 4-fold increase of sensitivity to pinprick stimuli in both extremities (hand: P<.05; foot: P<.001), a sensory pathway involved in withdrawal reflexes. Pinprick hyperalgesia was not paralleled by dynamic mechanical allodynia. Additional significant sensory changes were tactile hypoesthesia in both extremities (hand: P<.05; foot P<.01) and dysesthesia to non-noxious cold stimuli (paradoxical heat sensation), which was present in the foot in an unusually high proportion (14 of 40 patients; P<.01). In 8 patients, follow-up QST 2 to 20 months after treatment with l-DOPA (L-3,4-dihydroxyphenylalanine) revealed a significant reduction of pinprick hyperalgesia (-60%, P<.001), improved tactile detection (+50%, P<.05), and disappearance of paradoxical heat sensation in half of the patients. QST suggested a type of spinal or supraspinal central sensitization differing from neuropathic pain or human experimental models of central sensitization by the absence of dynamic mechanical allodynia. Reversal of pinprick hyperalgesia by l-DOPA may be explained by impaired descending inhibitory dopaminergic control on spinal nociceptive neurons. Restoration of tactile sensitivity and paradoxical heat sensations suggest that they were functional disturbances resulting from central disinhibition. PMID:23707286

Stiasny-Kolster, Karin; Pfau, Doreen B; Oertel, Wolfgang H; Treede, Rolf-Detlef; Magerl, Walter

2013-08-01

179

Characterization of tests of functional recovery after median and ulnar nerve injury and repair in the rat forelimb.  

PubMed

The majority of human peripheral nerve injuries occur in the upper limb but the majority of studies in the rat are performed in the hindlimb. The upper and lower limbs differ in dexterity and control by supraspinal systems, so an upper limb model is a better representation of the common form of human injury. The purpose of this study was to further develop a rat model involving lesions of the median and ulnar nerves. To produce different degrees of misdirection of axons following nerve repair, we studied nerve crush, cut and repair of the two nerves, and cut and repair with crossover. Assessment of functional recovery was performed using a battery of motor and sensory tests: the staircase test, which assesses skilled forepaw reaching; grip strength meter, which assesses grip strength; pawprint analysis, which assesses toe spread and print length; horizontal ladder, which assesses forepaw placement during skilled locomotion; modified Randall-Selitto device and electronic von Frey probes, which assess fine touch; and cold probes, which assess temperature sensation. All tests revealed deficits in forepaw function after nerve injury except the print length and modified Randall-Selitto device. The time course of functional recovery was observed over 15 weeks. The final degree of functional recovery achieved was related to the misdirection of axon regeneration. The tests that most clearly revealed the effects of axon misdirection on function were the skilled paw reaching and grip strength tests. The lesion model and functional tests that we have developed will be useful in testing therapeutic strategies for treating the consequences of inaccurate axon regeneration following peripheral nerve injury in humans. PMID:17374098

Galtrey, Clare M; Fawcett, James W

2007-03-01

180

Yield of the sural/radial ratio versus the medial plantar nerve in sensory neuropathies with a normal sural response.  

PubMed

The electrodiagnostic yield of the medial plantar nerve action potential (NAP) amplitude versus the sural/radial amplitude ratio (SRAR) was determined in 110 consecutive patients with clinically diagnosed distal sensory polyneuropathy (SN) and normal sural responses. Forty-five consecutive patients with clinically diagnosed lumbosacral radiculopathy served as disease controls. Of the 110 SN patients, 32 were classified clinically as SN with large-fiber involvement (SN-LFI), whereas 78 had clinically pure small-fiber SN. Plantar NAP amplitudes were abnormal in 18 of 32 patients (56%) with SN-LFI, and 15 of 78 (19%) with small-fiber SN. A SRAR <0.21 (fifth percentile of normal) was found in 7 of 32 patients (22%) with SN-LFI and 8 of 78 (10%) with small-fiber SN. In the control group, the medial plantar NAP was normal in all 45 subjects (100%), whereas the SRAR was >0.21 in 43 subjects (96%). Thus, for a 50% pretest probability of SN-LFI, the positive predictive value of an abnormal medial plantar was 100% versus 85% for a SRAR <0.21. The medial plantar NAP amplitude is a more useful measure of SN, than is the SRAR, in patients under age 70, with suspected SN-LFI. The yield of the SRAR and plantar NAP amplitude is poor when clinical signs of large-fiber sensory dysfunction are lacking. PMID:18340276

Sullivan, John P; Logigian, Eric L; Kocharian, Naira; Herrmann, David N

2008-04-01

181

A biomaterials approach to peripheral nerve regeneration: bridging the peripheral nerve gap and enhancing functional recovery  

PubMed Central

Microsurgical techniques for the treatment of large peripheral nerve injuries (such as the gold standard autograft) and its main clinically approved alternative—hollow nerve guidance conduits (NGCs)—have a number of limitations that need to be addressed. NGCs, in particular, are limited to treating a relatively short nerve gap (4 cm in length) and are often associated with poor functional recovery. Recent advances in biomaterials and tissue engineering approaches are seeking to overcome the limitations associated with these treatment methods. This review critically discusses the advances in biomaterial-based NGCs, their limitations and where future improvements may be required. Recent developments include the incorporation of topographical guidance features and/or intraluminal structures, which attempt to guide Schwann cell (SC) migration and axonal regrowth towards their distal targets. The use of such strategies requires consideration of the size and distribution of these topographical features, as well as a suitable surface for cell–material interactions. Likewise, cellular and molecular-based therapies are being considered for the creation of a more conductive nerve microenvironment. For example, hurdles associated with the short half-lives and low stability of molecular therapies are being surmounted through the use of controlled delivery systems. Similarly, cells (SCs, stem cells and genetically modified cells) are being delivered with biomaterial matrices in attempts to control their dispersion and to facilitate their incorporation within the host regeneration process. Despite recent advances in peripheral nerve repair, there are a number of key factors that need to be considered in order for these new technologies to reach the clinic. PMID:22090283

Daly, W.; Yao, L.; Zeugolis, D.; Windebank, A.; Pandit, A.

2012-01-01

182

Expression of p-Akt in Sensory Neurons and Spinal Cord after Peripheral Nerve Injury  

Microsoft Academic Search

Akt has been implicated in pro-survival and anti-apoptotic activities in many cell types, including dorsal root ganglion (DRG) and spinal motor neurons. In this immunohistochemical study we have monitored phosphorylated Akt (p-Akt) levels in adult mouse DRGs and spinal cord following unilateral peripheral sciatic nerve transection (axotomy) or carrageenan-induced inflammation. In control animals around half of the lumbar DRG neuron

Tie-Jun Sten Shi; Ping Huang; Jan Mulder; Sandra Ceccatelli; Tomas Hökfelt

2009-01-01

183

The impact and specificity of nerve perturbation on novel vibrotactile sensory letter learning.  

PubMed

The purposes of this study were to determine if induced radiating paresthesia interferes with (a) acquisition and/or (b) utilization of complex tactile information, and (c) identify whether interference reflects tactile masking or response competition. Radiating ulnar (experiment 1) and median (experiment 2) nerve paresthesia was quantified on ulnar innervated vibrotactile Morse code letter acquisition and recollection tasks. Induced paresthesia differentially impacted letter acquisition and recollection, but only when presented to the same anatomical spatial location. PMID:24844345

Passmore, Steven R; Bosse, Jessica; Murphy, Bernadette; Lee, Timothy D

2014-12-01

184

Sciatic nerve resection in the thigh: a functional evaluation.  

PubMed

Patients with a soft tissue malignancy involving the sciatic nerve who present with neurologic loss generally are advised to have an amputation. Twenty patients who underwent limb-sparing procedures with complete resection of the sciatic nerve as treatment for neurofibrosarcomas (12 patients), liposarcomas (four patients), malignant fibrous histiocytomas (two patients), recurrent desmoid tumor (one patient), and epithelioid hemangioendothelioma (one patient) were reviewed retrospectively. The mean age of these nine women and 11 men at the time of surgery was 51 years (range, 28-84 years). The right sciatic nerve was affected in 12 patients. These tumors were large and high grade. A mean of 22 cm of the nerve had to be resected (range, 8-42 cm). Ten patients received preoperative radiotherapy and 16 patients had intraoperative or postoperative radiotherapy. At a mean followup of 35 months (range, 7-97 months), 14 of the 20 patients were alive. Two patients had local recurrences develop (10%), whereas 12 patients had distant metastases. The function of the 10 patients as assessed by the Toronto Extremity Salvage Score averaged 74%. Most patients indicated that walking in the house is not difficult, but walking is compromised as soon as an effort is needed. Four patients walk without a cane, four needed one cane, and two needed two canes. The patients experienced stiffness, a sense of numbness, and premature fatigue. The use of analgesics was infrequent. Generally, patients rated themselves to be mildly to moderately disabled. From this small number of patients, it is shown that a tumor involving the sciatic nerve can be treated by limb-sparing surgery, including complete nerve resection, as an alternative to hip disarticulation or hindquarter amputation because the limb salvage option provides an acceptable functional outcome. PMID:11154002

Fuchs, B; Davis, A M; Wunder, J S; Bell, R S; Masri, B A; Isler, M; Turcotte, R; Rock, M G

2001-01-01

185

Effect of Lead Exposure and Ergonomic Stressors on Peripheral Nerve Function  

PubMed Central

In this study we investigated the effect of recent and chronic lead exposure, and its interaction with ergonomic stressors, on peripheral nerve function. In a cross-sectional design, we used retrospective exposure data on 74 primary lead smelter workers. We measured blood and bone lead levels and, from historical records, calculated lead dose metrics reflecting cumulative lead exposure: working-lifetime integrated blood lead (IBL) and working-lifetime weighted-average blood lead (TWA). We additionally created five metrics related to IBL that cumulated exposure only above increasing blood lead levels ranging from 20 to 60 ?g/dL (IBL20–IBL60). Current perception threshold (CPT) assessed large myelinated (CPT2000), small myelinated (CPT250), and unmyelinated (CPT5) sensory nerve fibers. Using multiple linear regression, we modeled CPT on the different measures of lead dose after adjusting for relevant covariates. CPT had a curvilinear relationship with TWA, with a minimum at a TWA of 28 ?g/dL. Both TWA and IBL accounted for a significant percentage of the variance of CPT2000 (?R2 = 8.7% and 3.9%, respectively). As the criterion blood lead level increased from IBL20 through IBL60, so did the percentage of CPT2000 variance explained, with ?R2 ranging from 5.8% (p < 0.03) for IBL20 to 23.3% (p < 0.00) for IBL60. IBL60 also significantly contributed to the explanation of variance of CPT250 and significantly interacted with ergonomic stressors. Measures of chronic blood lead exposure are associated with impairment of large and small myelinated sensory nerve fibers. This effect is enhanced at the highest doses by ergonomic stressors. PMID:16330355

Bleecker, Margit L.; Ford, D. Patrick; Vaughan, Christopher G.; Lindgren, Karen N.; Tiburzi, Michael J.; Walsh, Karin Scheetz

2005-01-01

186

Substitution of natural sensory input by artificial neurostimulation of an amputated trigeminal nerve does not prevent the degeneration of basal forebrain cholinergic circuits projecting to the somatosensory cortex  

PubMed Central

Peripheral deafferentation downregulates acetylcholine (ACh) synthesis in sensory cortices. However, the responsible neural circuits and processes are not known. We irreversibly transected the rat infraorbital nerve and implanted neuroprosthetic microdevices for proximal stump stimulation, and assessed cytochrome-oxidase and choline- acetyl-transferase (ChAT) in somatosensory, auditory and visual cortices; estimated the number and density of ACh-neurons in the magnocellular basal nucleus (MBN); and localized down-regulated ACh-neurons in basal forebrain using retrograde labeling from deafferented cortices. Here we show that nerve transection, causes down regulation of MBN cholinergic neurons. Stimulation of the cut nerve reverses the metabolic decline but does not affect the decrease in cholinergic fibers in cortex or cholinergic neurons in basal forebrain. Artifical stimulation of the nerve also has no affect of ACh-innervation of other cortices. Cortical ChAT depletion is due to loss of corticopetal MBN ChAT-expressing neurons. MBN ChAT downregulation is not due to a decrease of afferent activity or to a failure of trophic support. Basalocortical ACh circuits are sensory specific, ACh is provided to each sensory cortex “on demand” by dedicated circuits. Our data support the existence of a modality-specific cortex-MBN-cortex circuit for cognitive information processing. PMID:25452715

Herrera-Rincon, Celia; Panetsos, Fivos

2014-01-01

187

Strabismus and sensory-motor function of eye muscles.  

PubMed

Paul Bach-y-Rita and coworkers at the Smith-Kettlewell Institute of Visual Science of San Francisco were among the first to record activity in the muscle fibers of the eye muscles in animals. With their newly developed methods, they could describe fast and slow muscle fibers types and present possible patterns of recruitment of the fibers in different eye movements. These studies have been critical for continued animal research on eye muscle fibers and motor units in different species and in animals of different ages. Bach-y-Rita and coworkers also recorded from receptors in the muscles and demonstrated stretch reflexes different from those of skeletal muscles. Further research in animals revealed that it was difficult to delineate the functional role of the muscle receptors in oculomotor control. However, recent studies on sensory functions of human extra ocular muscles have suggested that proprioception participates in space localization, and the functions may differ in normal and strabismic subjects. The eye muscle studies initiated by Bach-y-Rita have enabled analysis of the sensory-motor components of strabismus or squint in greater detail than before. PMID:16385639

Lennerstrand, Gunnar

2005-12-01

188

Laminin Functionalized Biomimetic Nanofibers For Nerve Tissue Engineering  

PubMed Central

Large-gap peripheral nerve injuries present a significant challenge for nerve regeneration due to lack of suitable grafts, insufficient cell penetration, and repair. Biomimetic nanofibrous scaffolds, functionalized on the surface with extracellular matrix proteins, can lead to novel therapies for repair and regeneration of damaged peripheral nerves. Here, nanofibrous scaffolds electrospun from blends of poly(caprolactone) (PCL) and chitosan were fabricated. Taking advantage of the amine groups on the chitosan, the surface of the scaffolds were functionalized with laminin by carbodiimide based crosslinking. Crosslinking allowed laminin to be attached to the surfaces of the PCL-chitosan nanofibers at relatively high concentrations that were not possible using conventional adsorption methods. The nanofibrous meshes were tested for wettability, mechanical properties and cell attachment and proliferation. Blending of chitosan with PCL provided more favorable surfaces for attachment of Schwann cells due to the reduction of the contact angle in comparison to neat PCL. Proliferation rates of Schwann cells grown on PCL-chitosan scaffolds with crosslinked laminin were significantly higher than the rates for PCL-chitosan nanofibrous matrices with adsorbed laminin. PCL-chitosan scaffolds with modified surfaces via crosslinking of laminin could potentially serves as versatile substrates with excellent mechanical and surface properties for in vivo cell delivery for nerve tissue engineering applications. PMID:24083073

Junka, Radoslaw; Valmikinathan, Chandra M; Kalyon, Dilhan M; Yu, Xiaojun

2013-01-01

189

Evolutionary origins of sensation in metazoans: functional evidence for a new sensory organ in sponges  

PubMed Central

Background One of the hallmarks of multicellular organisms is the ability of their cells to trigger responses to the environment in a coordinated manner. In recent years primary cilia have been shown to be present as ‘antennae’ on almost all animal cells, and are involved in cell-to-cell signaling in development and tissue homeostasis; how this sophisticated sensory system arose has been little-studied and its evolution is key to understanding how sensation arose in the Animal Kingdom. Sponges (Porifera), one of the earliest evolving phyla, lack conventional muscles and nerves and yet sense and respond to changes in their fluid environment. Here we demonstrate the presence of non-motile cilia in sponges and studied their role as flow sensors. Results Demosponges excrete wastes from their body with a stereotypic series of whole-body contractions using a structure called the osculum to regulate the water-flow through the body. In this study we show that short cilia line the inner epithelium of the sponge osculum. Ultrastructure of the cilia shows an absence of a central pair of microtubules and high speed imaging shows they are non-motile, suggesting they are not involved in generating flow. In other animals non-motile, ‘primary’, cilia are involved in sensation. Here we show that molecules known to block cationic ion channels in primary cilia and which inhibit sensory function in other organisms reduce or eliminate sponge contractions. Removal of the cilia using chloral hydrate, or removal of the whole osculum, also stops the contractions; in all instances the effect is reversible, suggesting that the cilia are involved in sensation. An analysis of sponge transcriptomes shows the presence of several transient receptor potential (TRP) channels including PKD channels known to be involved in sensing changes in flow in other animals. Together these data suggest that cilia in sponge oscula are involved in flow sensation and coordination of simple behaviour. Conclusions This is the first evidence of arrays of non-motile cilia in sponge oscula. Our findings provide support for the hypothesis that the cilia are sensory, and if true, the osculum may be considered a sensory organ that is used to coordinate whole animal responses in sponges. Arrays of primary cilia like these could represent the first step in the evolution of sensory and coordination systems in metazoans. PMID:24410880

2014-01-01

190

Endogenous Prostaglandins and Afferent Sensory Nerves in Gastroprotective Effect of Hydrogen Sulfide against Stress-Induced Gastric Lesions  

PubMed Central

Hydrogen sulfide (H2S) plays an important role in human physiology, exerting vasodilatory, neuromodulatory and anti-inflammatory effects. H2S has been implicated in the mechanism of gastrointestinal integrity but whether this gaseous mediator can affect hemorrhagic lesions induced by stress has been little elucidated. We studied the effect of the H2S precursor L-cysteine, H2S-donor NaHS, the H2S synthesizing enzyme (CSE) activity inhibitor- D,L-propargylglycine (PAG) and the gastric H2S production by CSE/CBS/3-MST activity in water immersion and restraint stress (WRS) ulcerogenesis and the accompanying changes in gastric blood flow (GBF). The role of endogenous prostaglandins (PGs) and sensory afferent nerves releasing calcitonin gene-related peptide (CGRP) in the mechanism of gastroprotection induced by H2S was examined in capsaicin-denervated rats and those pretreated with capsazepine to inhibit activity of vanilloid receptors (VR-1). Rats were pretreated with vehicle, NaHS, the donor of H2S and or L-cysteine, the H2S precursor, with or without the concurrent treatment with 1) nonselective (indomethacin) and selective cyclooxygenase (COX)-1 (SC-560) or COX-2 (rofecoxib) inhibitors. The expression of mRNA and protein for COX-1 and COX-2 were analyzed in gastric mucosa pretreated with NaHS with or without PAG. Both NaHS and L-cysteine dose-dependently attenuated severity of WRS-induced gastric lesions and significantly increased GBF. These effects were significantly reduced by pretreatment with PAG and capsaicin denervation. NaHS increased gastric H2S production via CSE/CBS but not 3-MST activity. Inhibition of COX-1 and COX-2 activity significantly diminished NaHS- and L-cysteine-induced protection and hyperemia. NaHS increased expression of COX-1, COX-2 mRNAs and proteins and raised CGRP mRNA expression. These effects of NaHS on COX-1 and COX-2 protein contents were reversed by PAG and capsaicin denervation. We conclude that H2S exerts gastroprotection against WRS-induced gastric lesions by the mechanism involving enhancement in gastric microcirculation mediated by endogenous PGs, sensory afferent nerves releasing CGRP and the activation of VR-1 receptors. PMID:25774496

Magierowski, Marcin; Jasnos, Katarzyna; Kwiecien, Slawomir; Drozdowicz, Danuta; Surmiak, Marcin; Strzalka, Malgorzata; Ptak-Belowska, Agata; Wallace, John L.; Brzozowski, Tomasz

2015-01-01

191

Endogenous Prostaglandins and Afferent Sensory Nerves in Gastroprotective Effect of Hydrogen Sulfide against Stress-Induced Gastric Lesions.  

PubMed

Hydrogen sulfide (H2S) plays an important role in human physiology, exerting vasodilatory, neuromodulatory and anti-inflammatory effects. H2S has been implicated in the mechanism of gastrointestinal integrity but whether this gaseous mediator can affect hemorrhagic lesions induced by stress has been little elucidated. We studied the effect of the H2S precursor L-cysteine, H2S-donor NaHS, the H2S synthesizing enzyme (CSE) activity inhibitor- D,L-propargylglycine (PAG) and the gastric H2S production by CSE/CBS/3-MST activity in water immersion and restraint stress (WRS) ulcerogenesis and the accompanying changes in gastric blood flow (GBF). The role of endogenous prostaglandins (PGs) and sensory afferent nerves releasing calcitonin gene-related peptide (CGRP) in the mechanism of gastroprotection induced by H2S was examined in capsaicin-denervated rats and those pretreated with capsazepine to inhibit activity of vanilloid receptors (VR-1). Rats were pretreated with vehicle, NaHS, the donor of H2S and or L-cysteine, the H2S precursor, with or without the concurrent treatment with 1) nonselective (indomethacin) and selective cyclooxygenase (COX)-1 (SC-560) or COX-2 (rofecoxib) inhibitors. The expression of mRNA and protein for COX-1 and COX-2 were analyzed in gastric mucosa pretreated with NaHS with or without PAG. Both NaHS and L-cysteine dose-dependently attenuated severity of WRS-induced gastric lesions and significantly increased GBF. These effects were significantly reduced by pretreatment with PAG and capsaicin denervation. NaHS increased gastric H2S production via CSE/CBS but not 3-MST activity. Inhibition of COX-1 and COX-2 activity significantly diminished NaHS- and L-cysteine-induced protection and hyperemia. NaHS increased expression of COX-1, COX-2 mRNAs and proteins and raised CGRP mRNA expression. These effects of NaHS on COX-1 and COX-2 protein contents were reversed by PAG and capsaicin denervation. We conclude that H2S exerts gastroprotection against WRS-induced gastric lesions by the mechanism involving enhancement in gastric microcirculation mediated by endogenous PGs, sensory afferent nerves releasing CGRP and the activation of VR-1 receptors. PMID:25774496

Magierowski, Marcin; Jasnos, Katarzyna; Kwiecien, Slawomir; Drozdowicz, Danuta; Surmiak, Marcin; Strzalka, Malgorzata; Ptak-Belowska, Agata; Wallace, John L; Brzozowski, Tomasz

2015-01-01

192

The quantitative contribution of nitric oxide and sensory nerves to bradykinin-induced inflammation in rat skin microvasculature.  

PubMed

Using a blister model in the rat hind footpad, the present study undertook to examine the relative contribution of sensory nerves and nitric oxide (NO) to the inflammatory response induced by bradykinin (BK). Using this model, combined with laser Doppler flowmetry, we were able to simultaneously monitor two parameters of the inflammatory response, namely vasodilatation (VD) and plasma extravasation (PE). Perfusion of BK (1, 10 or 100 microM) over the blister base elicited both VD and PE responses which were dose-dependent. The VD response was of rapid onset, sustained at the lowest concentration (1 microM), and showed tachyphylaxis at the highest two concentrations (10 and 100 microM). The PE response, however, was delayed in onset at the lower concentration but the response was maintained at all concentrations. The endothelium-independent vasodilator, sodium nitroprusside. (SNP, 100 microM), was used as an internal control and elicited a rapid maintained VD response. In rats pretreated as neonates with capsaicin to destroy primary sensory afferents, the inflammatory response to 10 microM BK was significantly smaller (50% and 64% decrease in VD and PE, respectively). The selective inhibitor of NO synthase, NG-nitro-L-arginine (L-NORAG) at 100 microM significantly attenuated the inflammatory response to BK in control rats (76% and 60% decrease in VD and PE, respectively) with a further decrease in the response in capsaicin pretreated rats. The inactive stereoisomer NG-nitro-D-arginine (D-NORAG) (100 microM) did not affect the inflammatory response to BK. The vasodilator response to SNP was intact in capsaicin pretreated rats and was not affected by either L-NORAG or D-NORAG.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1384924

Khalil, Z; Helme, R D

1992-08-28

193

Evolution of peripheral nerve function in humans: novel insights from motor nerve excitability  

PubMed Central

While substantial alterations in myelination and axonal growth have been described during maturation, their interactions with the configuration and activity of axonal membrane ion channels to achieve impulse conduction have not been fully elucidated. The present study utilized axonal excitability techniques to compare the changes in nerve function across healthy infants, children, adolescents and adults. Multiple excitability indices (stimulus–response curve, strength–duration time constant, threshold electrotonus, current–threshold relationship and recovery cycle) combined with conventional neurophysiological measures were investigated in 57 subjects (22 males, 35 females; age range 0.46–24 years), stimulating the median motor nerve at the wrist. Maturational changes in conduction velocity were paralleled by significant alterations in multiple excitability parameters, similarly reaching steady values in adolescence. Maturation was accompanied by reductions in threshold (P < 0.005) and rheobase (P= 0.001); depolarizing and hyperpolarizing electrotonus progressively reduced (P < 0.001), or ‘fanned-in’; resting current–threshold slope increased (P < 0.0001); accommodation to depolarizing currents prolonged (P < 0.0001); while greater threshold changes in refractoriness (P= 0.001) and subexcitability (P < 0.01) emerged. Taken together, the present findings suggest that passive membrane conductances and the activity of K+ conductances decrease with formation of the axo-glial junction and myelination. In turn, these functional alterations serve to enhance the efficiency and speed of impulse conduction concurrent with the acquisition of motor skills during childhood, and provide unique insight into the evolution of postnatal human peripheral nerve function. Significantly, these findings bring the dynamics of axonal development to the clinical domain and serve to further illuminate pathophysiological mechanisms that occur during development. PMID:23006483

Farrar, Michelle A; Park, Susanna B; Lin, Cindy S-Y; Kiernan, Matthew C

2013-01-01

194

Relationship of estimated dietary intake of n-3 polyunsaturated fatty acids from fish with peripheral nerve function after adjusting for mercury exposure  

PubMed Central

Background Some clinical studies have suggested that ingestion of n-3 polyunsaturated fatty acids (PUFA) has neuroprotective effects on peripheral nerve function. However, few epidemiological studies have examined the effect of dietary n-3 PUFA intake from fish consumption on peripheral nerve function, and none have controlled for co-occurrence of methylmercury exposure from fish consumption. Objectives We evaluated the effect of estimated dietary n-3 PUFA intake on peripheral nerve function after adjusting for biomarkers of methylmercury and elemental mercury in a convenience sample of 515 dental professionals. Methods We measured sensory nerve conduction (peak latency and amplitude) of the median, ulnar and sural nerves and total mercury concentrations in hair and urine samples. We estimated daily intake (mg/day) of the total n-3 PUFA, n-3 docosahexaenoic acid (DHA), and n-3 eicosapentaenoic acid (EPA) based on a self-administrated fish consumption frequency questionnaire. We also collected information on mercury exposure, demographics and other covariates. Results The estimated median intakes of total n-3 PUFA, n-3 EPA, and n-3 DHA were 447, 105, and 179 mg/day, respectively. The mean mercury concentrations in urine (1.05?g/L) and hair (0.49?g/g) were not significantly different from the US general population. We found no consistent association between n-3 PUFA intake and sensory nerve conduction after adjusting for mercury concentrations in hair and urine although some positive associations were observed with the sural nerve. Conclusions In a convenience sample of dental professionals, we found little evidence suggesting that dietary intake of n-3 PUFAs from fish has any impact on peripheral nerve function after adjustment for methylmercury exposure from fish and elemental mercury exposure from dental amalgam. PMID:23538138

Wang, Yi; Goodrich, Jaclyn M.; Werner, Robert; Gillespie, Brenda; Basu, Niladri; Franzblau, Alfred

2013-01-01

195

Functional Recovery After Facial and Sciatic Nerve Crush Injury in the Rat  

Microsoft Academic Search

Objectives: To systematically record rat facial nerve re- covery following crush injury to the main trunk with re- spect to ocular and vibrissial function and to compare the rates of facial and sciatic nerve recovery from crush injury in the same animals. This serves as a means of vali- dating the functional parameters of facial nerve recov- ery against the

Tessa A. Hadlock; James Heaton; Mack Cheney; Susan E. Mackinnon

2005-01-01

196

Long term functional plasticity of sensory inputs mediated by olfactory learning  

PubMed Central

Sensory inputs are remarkably organized along all sensory pathways. While sensory representations are known to undergo plasticity at the higher levels of sensory pathways following peripheral lesions or sensory experience, less is known about the functional plasticity of peripheral inputs induced by learning. We addressed this question in the adult mouse olfactory system by combining odor discrimination studies with functional imaging of sensory input activity in awake mice. Here we show that associative learning, but not passive odor exposure, potentiates the strength of sensory inputs up to several weeks after the end of training. We conclude that experience-dependent plasticity can occur in the periphery of adult mouse olfactory system, which should improve odor detection and contribute towards accurate and fast odor discriminations. DOI: http://dx.doi.org/10.7554/eLife.02109.001 PMID:24642413

Abraham, Nixon M; Vincis, Roberto; Lagier, Samuel; Rodriguez, Ivan; Carleton, Alan

2014-01-01

197

?-Synuclein in cutaneous autonomic nerves  

PubMed Central

Objective: To develop a cutaneous biomarker for Parkinson disease (PD). Methods: Twenty patients with PD and 14 age- and sex-matched control subjects underwent examinations, autonomic testing, and skin biopsies at the distal leg, distal thigh, and proximal thigh. ?-Synuclein deposition and the density of intraepidermal, sudomotor, and pilomotor nerve fibers were measured. ?-Synuclein deposition was normalized to nerve fiber density (the ?-synuclein ratio). Results were compared with examination scores and autonomic function testing. Results: Patients with PD had a distal sensory and autonomic neuropathy characterized by loss of intraepidermal and pilomotor fibers (p < 0.05 vs controls, all sites) and morphologic changes to sudomotor nerve fibers. Patients with PD had greater ?-synuclein deposition and higher ?-synuclein ratios compared with controls within pilomotor nerves and sudomotor nerves (p < 0.01, all sites) but not sensory nerves. Higher ?-synuclein ratios correlated with Hoehn and Yahr scores (r = 0.58–0.71, p < 0.01), with sympathetic adrenergic function (r = ?0.40 to ?0.66, p < 0.01), and with parasympathetic function (r = ?0.66 to ?0.77, p > 0.01). Conclusions: We conclude that ?-synuclein deposition is increased in cutaneous sympathetic adrenergic and sympathetic cholinergic fibers but not sensory fibers of patients with PD. Higher ?-synuclein deposition is associated with greater autonomic dysfunction and more advanced PD. These data suggest that measures of ?-synuclein deposition in cutaneous autonomic nerves may be a useful biomarker in patients with PD. PMID:24089386

Wang, Ningshan; Gibbons, Christopher H.; Lafo, Jacob

2013-01-01

198

Improvement of Sciatic Nerve Regeneration Using Laminin-Binding Human NGF-beta  

Microsoft Academic Search

BackgroundSciatic nerve injuries often cause partial or total loss of motor, sensory and autonomic functions due to the axon discontinuity, degeneration, and eventual death which finally result in substantial functional loss and decreased quality of life. Nerve growth factor (NGF) plays a critical role in peripheral nerve regeneration. However, the lack of efficient NGF delivery approach limits its clinical applications.

Wenjie Sun; Changkai Sun; Hui Zhao; Hang Lin; Qianqian Han; Jingyu Wang; Hui Ma; Bing Chen; Zhifeng Xiao; Jianwu Dai; Xiao-Jiang Li

2009-01-01

199

Assessment of Brainstem Function with Auricular Branch of Vagus Nerve Stimulation in Parkinson’s Disease  

PubMed Central

Background The efferent dorsal motor nucleus of the vagal nuclei complex may degenerate early in the course of Parkinson’s disease (PD), while efferent nucleus ambiguous, the principal source of parasympathetic vagal neurons innervating the heart, and afferent somatosensory nuclei remain intact. Objective To obtain neurophysiological evidence related to this pattern, we tested processing of afferent sensory information transmitted via the auricular branch of the vagus nerve (ABVN) which is known to be connected to autonomic regulation of cardiac rhythm. Methods In this cross-sectional observational study, we recorded (i) somatosensory evoked potentials (ABVN-SEP) and (ii) cutaneo-cardioautonomic response elicited by stimulation of the ABVN (modulation of heart-rate variability (HRV index; low frequency power, ln(LF), high frequency power, ln(HF); ln(LF/HF) ratio)) in 50 PD patients and 50 age and sex matched healthy controls. Additionally, auditory evoked potentials and trigeminal nerve SEP were assessed. Results Neither ABVN-SEP nor any of the other functional brainstem parameters differed between patients and controls. Although HRV index was decreased in PD patients, modulation of ln(LF/HF) by ABVN-stimulation, likely indicating cardiac parasympathetic activation, did not differ between both groups. Conclusions Findings do not point to prominent dysfunction of processing afferent information from ABVN and its connected parasympathetic cardiac pathway in PD. They are consistent with the known pattern of degeneration of the vagal nuclei complex of the brainstem. PMID:25849807

Weise, David; Adamidis, Melanie; Pizzolato, Fabio; Rumpf, Jost-Julian; Fricke, Christopher; Classen, Joseph

2015-01-01

200

Low-Level Laser Irradiation Improves Functional Recovery and Nerve Regeneration in Sciatic Nerve Crush Rat Injury Model  

PubMed Central

The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm2 and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm2. Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm2 had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm2. Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm2. Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm2 and 8 J/cm2) is capable of enhancing sciatic nerve regeneration following a crush injury. PMID:25119457

Wang, Chau-Zen; Chen, Yi-Jen; Wang, Yan-Hsiung; Yeh, Ming-Long; Huang, Mao-Hsiung; Ho, Mei-Ling; Liang, Jen-I; Chen, Chia-Hsin

2014-01-01

201

Partial Recovery of Respiratory Function and Diaphragm Reinnervation following Unilateral Vagus Nerve to Phrenic Nerve Anastomosis in Rabbits  

PubMed Central

Respiratory dysfunction is the leading cause of mortality following upper cervical spinal cord injury (SCI). Reinnervation of the paralyzed diaphragm via an anastomosis between phrenic nerve and a donor nerve is a potential strategy to mitigate ventilatory deficits. In this study, anastomosis of vagus nerve (VN) to phrenic nerve (PN) in rabbits was performed to assess the potential capacity of the VN to compensate for lost PN inputs. At first, we compared spontaneous discharge pattern, nerve thickness and number of motor fibers between these nerves. The PN exhibited a highly rhythmic discharge while the VN exhibited a variable frequency discharge pattern. The rabbit VN had fewer motor axons (105.3±12.1 vs. 268.1±15.4). Nerve conduction and respiratory function were measured 20 weeks after left PN transection with or without left VN-PN anastomosis. Compared to rabbits subjected to unilateral phrenicotomy without VN-PN anastomosis, diaphragm muscle action potential (AP) amplitude was improved by 292%, distal latency by 695%, peak inspiratory flow (PIF) by 22.6%, peak expiratory flow (PRF) by 36.4%, and tidal volume by 21.8% in the anastomosis group. However, PIF recovery was only 28.0%, PEF 28.2%, and tidal volume 31.2% of Control. Our results suggested that VN-PN anastomosis is a promising therapeutic strategy for partial restoration of diaphragm reinnervation, but further modification and improvements are necessary to realize the full potential of this technique. PMID:24265777

Li, Lijun; Sun, Guixin; Tan, Jun

2013-01-01

202

Leptin in gastroprotection induced by cholecystokinin or by a meal. Role of vagal and sensory nerves and nitric oxide.  

PubMed

Leptin, detected recently in the stomach, is a product of the ob gene released by cholecystokinin (CCK) and plays an important role in the control of food intake but its influence on gastroprotection against the damage caused by noxious agents has not been studied. This study was designed to compare the effects of leptin and cholecystokinin-8 (CCK-8) on gastric mucosal lesions induced by topical application of 75% ethanol or acidified aspirin. Four series of Wistar rats (A, B, C and D) were used to determine the effects of: (A) suppression of prostaglandin biosynthesis by indomethacin (5 mg/kg i.p.); (B) inhibition of nitric oxide (NO)-synthase by nitro-L-arginine methyl ester (L-NAME) (5 mg/kg i.v.); (C) blockade of sensory nerves by capsaicin (125 mg/kg s.c.) and (D) bilateral vagotomy, on the gastric lesions induced by intragastric (i.g.) application of ethanol with or without pretreatment with CCK-8, a known gastroprotective substance or leptin. CCK-8 (1-100 microg/kg i.p.) and leptin (0.1-50 microg/kg i.p.) dose dependently attenuated gastric lesions induced by 75% ethanol; the dose reducing these lesions by 50% being about 10 microg/kg and 8 microg/kg, respectively. The protective effects of CCK-8 and leptin were accompanied by a significant rise in gastric blood flow (GBF) and luminal NO concentration. Leptin was also effective to attenuate aspirin-induced damage and the accompanying fall in the GBF, whereas CCK-8 dose dependently worsened aspirin damage and failed to influence GBF. CCK (1-100 microg/kg i.p.), given in graded doses, produced a dose-dependent increase in the plasma leptin level and a rise of the expression of ob messenger RNA (mRNA) in gastric mucosa, the maximum being reached at a dose of 100 microg/kg. Pretreatment with CCK-8 (10 microg/kg i.p.) or with 8% peptone, that is known to stimulate CCK release, also produced a significant rise in plasma leptin levels and up-regulation of ob mRNA while reducing significantly the gastric lesions induced by 75% ethanol to the same extent as that induced by exogenous leptin (10 microg/kg i.p.). Indomethacin, which suppressed prostaglandin generation by approximately 90%, failed to influence leptin- or CCK-8-induced protection against ethanol, whereas L-NAME attenuated significantly CCK-8- and leptin-induced protection and hyperemia but addition to L-NAME of L-arginine, but not D-arginine, restored the protective and hyperemic effects of both hormones. The ob mRNA was detected as a weak signal in the intact gastric mucosa and in that exposed to ethanol alone but this was further enhanced after treatment with graded doses of CCK-8 or peptone meal applied prior to ethanol. We conclude that: (1) exogenous leptin or that released endogenously by CCK or meal exerts a potent gastroprotective action depending upon vagal activity, and involving hyperemia probably mediated by NO and sensory nerves but unrelated to endogenous prostaglandins; (2) leptin mimics the gastroprotective effect of CCK and probably mediates the protective and hyperemic actions of CCK in the rat stomach. PMID:10422768

Brzozowski, T; Konturek, P C; Konturek, S J; Pajdo, R; Duda, A; Pierzchalski, P; Biela?ski, W; Hahn, E G

1999-06-18

203

The involvement of CGRP, adrenomedullin, and sensory nerves in remote vasomotor responses within the hamster cheek pouch microcirculation.  

PubMed

Previous work from our laboratory demonstrated a role for sensory nerves in remote dilations to microapplied methacholine by blocking the response with CGRP8-37 and concluded CGRP was the neurotransmitter. Recently, a more specific CGRP receptor antagonist, BIBN4096BS, was developed. The goals of the present study are to characterize the effects of BIBN4096BS on vasomotor responses in the hamster cheek pouch microcirculation, and to verify the role of CGRP in remote dilations to capsaicin and methacholine and to test adrenomedullin as an alternative neurotransmitter. BIBN4096BS pretreatment inhibits dilation to CGRP while having no significant effect on baseline diameter, it shifts the EC(50) to superfused CGRP from 1.5+/-0.3 pM to 2.5+/-0.6 nM and it shifts the apparent EC(50) to capsaicin from 31.5 nM to 171 nM. Local and remote dilations caused by the microapplication of methacholine are not inhibited by 300 nM BIBN4096BS (Local: 9.7+/-1.2 versus 9.7+/-1.5; 500:5.5+/-0.4 versus 5.7+/-0.5; 1000:4.4+/-0.6 versus 4.8+/-0.5). Remote dilations to methacholine were significantly inhibited however when adrenomedullin receptor antagonist adrenomedullin-(26-52) was microapplied to the remote site. Perivascular neurons containing adrenomedullin can be detected with immunohistochemistry. The results, combined with previous work, suggest that adrenomedullin, and not CGRP, is involved in remote dilations to methacholine. PMID:19084542

Miriel, Victor A; Chen, Yifan; Rivers, Richard J

2009-03-01

204

Role of prostaglandins, nitric oxide, sensory nerves and gastrin in acceleration of ulcer healing by melatonin and its precursor, L-tryptophan.  

PubMed

Melatonin, a major hormone of pineal gland, was recently shown to attenuate acute gastric lesions induced by strong irritants because of the scavenging of free radicals but its role in ulcer healing has been little investigated. In this study we compared the effects of intragastric (i.g.) administration of melatonin and its precursor, L-tryptophan, with or without concurrent treatment with luzindole, a selective antagonist of melatonin MT2 receptors, on healing of chronic gastric ulcers induced by serosal application of acetic acid (ulcer area 28 mm2). The involvement of endogenous prostaglandins (PG), nitric oxide (NO) and sensory nerves in ulcer healing action of melatonin and L-tryptophan was studied in rats treated with indomethacin and NG-nitro-L-arginine (L-NNA) to suppress, respectively, cyclo-oxygenases (COX) and NO synthases or in those with functionally deactivated sensory nerves with capsaicin. The influence of melatonin on gastric secretion during ulcer healing was tested in separate group of rats with gastric ulcer equipped with gastric fistulas (GF). At day 8 and 15 upon the ulcer induction, the area of gastric ulcers was measured by planimetry, the mucosal blood flow (GBF) was determined by H2-gas clearance technique and gastric luminal NO2-/NO3- levels was assessed by Griess reaction. Plasma melatonin and gastrin levels were measured by specific radioimmunoassay (RIA). Biopsy mucosal samples were taken for expression of constitutive NO-synthase (cNOS) and inducible NOS (iNOS) by reverse transcriptase-polymerase chain reaction (RT-PCR). Melatonin (2.5-20 mg/kg-d i.g.) and L-tryptophan (25-100 mg/kg-d i.g.) dose-dependently accelerated ulcer healing, the dose inhibiting by 50% (ED50) of ulcer area being 10 and 115 mg/kg, respectively. This inhibitory effect of melatonin (10 mg/kg-d i.g.) and L-tryptophan (100 mg/kg-d i.g.) on ulcer healing was accompanied by a significant rise in the GBF at ulcer margin and an increase of plasma melatonin. luminal NO2-/NO3- and plasma gastrin levels. Gastric acid and pepsin outputs were significantly inhibited during the ulcer healing in melatonin-treated gastric mucosa as compared with those in vehicle-treated animals. Luzindole abolished completely the healing effects of melatonin and L-tryptophan and attenuated significantly the rise in plasma gastrin evoked by the hormone and its precursor. Indomethacin (5 mg/kg-d i.p). that blocked PG biosynthesis by 90% or L-NAME (20 mg/kg i.v), inhibitor of NOS. that suppressed luminal NO release, attenuated significantly melatonin and L-tryptophan-induced acceleration of ulcer healing and accompanying rise in GBF at ulcer margin and luminal NO release. The melatonin-induced acceleration of ulcer healing, hyperemia at ulcer margin and increase in the release of NO were enhanced when L-arginine but not D-arginine was added to L-NAME. The ulcer healing and the GBF effects of melatonin and L-tryptophan were significantly impaired in rats with capsaicin-induced denervation of sensory nerves and both, ulcer healing and the hyperemia at ulcer margin were restored in these rats by addition of exogenous CGRP to melatonin and L-tryptophan. Expression of cNOS mRNA was detected by RT-PCR in the intact gastric mucosa as well as at the edge of gastric ulcers treated with both, vehicle and melatonin, while iNOS mRNA that was undetectable in the intact gastric mucosa, appeared during ulcer healing and especially this was strongly up-regulated in the melatonin-treated gastric mucosa. We conclude that (1) exogenous melatonin and that derived from its precursor, L-tryptophan, accelerate ulcer healing probably via interaction with MT2 receptors; (2) this ulcer healing action is caused by an enhancement by melatonin of the microcirculation at the ulcer margin possibly mediated by COX-derived PG and NO because of overexpression of iNOS and (3) gastrin, which exhibits trophic activity in the gastric mucosa and calcitonin gene related peptide (CGRP), released from sensory nerves, may also contribute to the ulcer healing action of melatonin. PMID:12074098

Brzozowska, Iwona; Konturek, Peter C; Brzozowski, Tomasz; Konturek, Stanislaw J; Kwiecien, Slawomir; Pajdo, Robert; Drozdowicz, Danuta; Pawlik, Michal; Ptak, Agata; Hahn, Eckhart G

2002-04-01

205

Sensory axon guidance with semaphorin 6A and nerve growth factor in a biomimetic choice point model.  

PubMed

The direct effect of guidance cues on developing and regenerating axons in vivo is not fully understood, as the process involves a multiplicity of attractive and repulsive signals, presented both as soluble and membrane-bound ligands. A better understanding of axon guidance is critical to functional recovery following injury to the nervous system through improved outgrowth and mapping of damaged nerves. Due to their implications as inhibitors to central nervous system regeneration, we investigated the repulsive properties of semaphorin 6A and ephrin-B3 on E15 rat dorsal root ganglion explants, as well as possible interactions with soluble gradients of chemoattractive nerve growth factor (NGF). We employed a 3D biomimetic in vitro choice point model, which enabled the simple and rapid preparation of patterned gel growth matrices with quantifiable presentation of guidance cues in a specifiable manner that resembles the in vivo presentation of soluble and/or immobilized ligands. Neurites demonstrated an inhibitory response to immobilized Sema6A by lumbosacral dorsal root ganglion explants, while no such repulsion was observed for immobilized ephrin-B3 by explants at any spinal level. Interestingly, Sema6A inhibition could be partially attenuated in a concentration-dependent manner through the simultaneous presentation of soluble NGF gradients. The in vitro model described herein represents a versatile and valuable investigative tool in the quest for understanding developmental processes and improving regeneration following nervous system injury. PMID:25189126

Curley, J Lowry; Catig, Gary C; Horn-Ranney, Elaine L; Moore, Michael J

2014-09-01

206

Long-Term Functional Recovery after Facial Nerve Transection and Repair in the Rat  

PubMed Central

Background The rodent model is commonly used to study facial nerve injury. Because of the exceptional regenerative capacity of the rodent facial nerve, it is essential to consider the timing when studying facial nerve regeneration and functional recovery. Short-term functional recovery data following transection and repair of the facial nerve has been documented by our laboratory. However, because of the limitations of the head fixation device, there is a lack of long-term data following facial nerve injury. The objective of this study was to elucidate the long-term time course and functional deficit following facial nerve transection and repair in a rodent model. Methods Adult rats were divided into group 1 (controls) and group 2 (experimental). Group 1 animals underwent head fixation, followed by a facial nerve injury, and functional testing was performed from day 7 to day 70. Group 2 animals underwent facial nerve injury, followed by delayed head fixation, and then underwent functional testing from months 6 to 8. Results There was no statistical difference between the average whisking amplitudes in group 1 and group 2 animals. Conclusion Functional whisking recovery 6 months after facial nerve injury is comparable to recovery within 1 to 4 months of transection and repair, thus the ideal window for evaluating facial nerve recovery falls within the 4 months after injury. PMID:25629206

Banks, Caroline A.; Knox, Christopher; Hunter, Daniel A.; Mackinnon, Susan E.; Hohman, Marc H.; Hadlock, Tessa A.

2015-01-01

207

Long-term functional recovery after facial nerve transection and repair in the rat.  

PubMed

Background?The rodent model is commonly used to study facial nerve injury. Because of the exceptional regenerative capacity of the rodent facial nerve, it is essential to consider the timing when studying facial nerve regeneration and functional recovery. Short-term functional recovery data following transection and repair of the facial nerve has been documented by our laboratory. However, because of the limitations of the head fixation device, there is a lack of long-term data following facial nerve injury. The objective of this study was to elucidate the long-term time course and functional deficit following facial nerve transection and repair in a rodent model. Methods?Adult rats were divided into group 1 (controls) and group 2 (experimental). Group 1 animals underwent head fixation, followed by a facial nerve injury, and functional testing was performed from day 7 to day 70. Group 2 animals underwent facial nerve injury, followed by delayed head fixation, and then underwent functional testing from months 6 to 8. Results?There was no statistical difference between the average whisking amplitudes in group 1 and group 2 animals. Conclusion?Functional whisking recovery 6 months after facial nerve injury is comparable to recovery within 1 to 4 months of transection and repair, thus the ideal window for evaluating facial nerve recovery falls within the 4 months after injury. PMID:25629206

Banks, Caroline A; Knox, Christopher; Hunter, Daniel A; Mackinnon, Susan E; Hohman, Marc H; Hadlock, Tessa A

2015-03-01

208

Expression and Function of Nerve Growth Factor and Nerve Growth Factor Receptor on Cultured Keratinocytes  

Microsoft Academic Search

Keratinocytes, a key cellular component both for homeostasis and pathophysiologic processes of the skin, secrete a number of cytokines and are stimulated by several growth factors. Nerve growth factor (NGF) is synthesized in the skin and basal keratinocytes express the low-affinity nerve growth factor receptor (NGF-R). We present evidence that normal human keratinocytes in culture express the low- and the

Carlo Pincelli; Cinzia Sevignani; Rossella Manfredini; Alexis Grande; Fabrizio Fantini; Luisa Bracci-Laudiero; Luigi Aloe; Sergio Ferrari; Andrea Cossarizza; Alberto Giannetti

1994-01-01

209

Bladder and cutaneous sensory neurons of the rat express different functional p2x receptors  

Microsoft Academic Search

The expression and functional responses of P2X receptors in bladder and cutaneous sensory neurons of adult rats and mice have been studied using immunohistochemistry and patch clamp techniques. Cell bodies of bladder pelvic afferents were identified in L6 and S1 dorsal root ganglia (DRG), following Fast Blue injection into the muscle wall of the urinary bladder. Similarly, cutaneous sensory neurons

Y Zhong; A. S Banning; D. A Cockayne; A. P. D. W Ford; G Burnstock; S. B Mcmahon

2003-01-01

210

Functionally Approached Body (FAB) Strategies for Young Children Who Have Behavioral and Sensory Processing Challenges  

ERIC Educational Resources Information Center

Functionally Approached Body (FAB) Strategies offer a clinical approach to help parents of young children with behavioral and sensory processing strategies. This article introduces the FAB Strategies, clinical strategies developed by the author for understanding and addressing young children's behavioral and sensory processing challenges. The FAB…

Pagano, John

2005-01-01

211

NonRandom Distribution and Sensory Functions of Primary Cilia in Vascular Smooth Muscle Cells  

Microsoft Academic Search

Although primary cilia are increasingly recognized to play sensory roles in several cellular systems, their role in vascular smooth muscle cells (VSMCs) has not been defined. We examined in situ position\\/orientation of primary cilia and ciliary proteins in VSMCs and tested the hypothesis that primary cilia of VSMCs exert sensory functions. By immunofluorescence and electron microscopic imaging, primary cilia of

C. J. Lu; H. Du; J. Wu; D. A. Jansen; K. L. Jordan; N. Xu; G. C. Sieck; Q. Qian

2008-01-01

212

Biomechanical and functional variation in rat sciatic nerve following cuff electrode implantation  

PubMed Central

Background Nerve cuff electrodes are commonly and successfully used for stimulating peripheral nerves. On the other hand, they occasionally induce functional and morphological changes following chronic implantation, for reasons not always clear. We hypothesize that restriction of nerve mobility due to cuff implantation may alter nerve conduction. Methods We quantified acute changes in nerve-muscle electrophysiology, using electromyography, and nerve kinematics in anesthetized Sprague Dawley rat sciatic nerves during controlled hindlimb joint movement. We compared electrophysiological and biomechanical response in uncuffed nerves and those secured within a cuff electrode using analysis of variance (ANOVA) and regression analysis. Results Tethering resulting from cuff implantation resulted in altered nerve strain and a complex biomechanical environment during joint movement. Coincident with biomechanical changes, electromyography revealed significantly increased variability in the response of conduction latency and amplitude in cuffed, but not free, nerves following joint movement. Conclusion Our findings emphasize the importance of the mechanical interface between peripheral nerves and their devices on neurophysiological performance. This work has implications for nerve device design, implantation, and prediction of long-term efficacy. PMID:24758405

2014-01-01

213

Manual stimulation of facial muscles improves functional recovery after hypoglossal–facial anastomosis and interpositional nerve grafting of the facial nerve in adult rats  

Microsoft Academic Search

The facial nerve in humans is often prone to injuries requiring surgical intervention. In the best case, nerve reconstruction is achieved by a facial–facial anastomosis (FFA), i.e. suture of the proximal and distal stumps of the severed facial nerve. Although a method of choice, FFA rarely leads to a satisfactory functional recovery. We have recently devised and validated, in an

Orlando Guntinas-Lichius; Gregor Hundeshagen; Thomas Paling; Michael Streppel; Maria Grosheva; Andrey Irintchev; Emmanouil Skouras; Athanasia Alvanou; Srebrina K. Angelova; Stefanie Kuerten; Nektarios Sinis; Sarah A. Dunlop; Doychin N. Angelov

2007-01-01

214

Differential activation of mitogen-activated protein kinases and glial cells in the trigeminal sensory nuclear complex following lingual nerve injury.  

PubMed

Mitogen-activated protein kinases (MAPKs) play a pivotal role in the mediation of cellular responses to a variety of signaling molecules. The current study demonstrates phosphorylation of extracellular signal-regulated kinase (ERK) and p38 MAPK in each subdivision of the trigeminal sensory nuclear complex (TSNC) following lingual nerve injury. Immunohistochemical labeling for phosphorylated ERK (p-ERK) or phosphorylated p38 (p-p38) MAPK was performed in histological sections of the brainstem. A transient increase in the immunoreactivity for p-ERK was found in each subdivision of the TSNC followed by a prolonged increase in the immunoreactivity for p-p38 MAPK after nerve injury. Double immunofluorescence labeling with cell-specific markers revealed that ERK and p38 MAPK were phosphorylated predominantly by OX-42-positive microglia or GFAP-positive astrocytes. Increased immunofluorescence labeling for OX-42 and GFAP indicated that microglia and astrocytes were activated by nerve injury in the TSNC. Activation of MAPKs and glial cells in the rostral subdivisions of the TSNC was comparable with that in the subnucleus caudalis of the trigeminal spinal tract nucleus (Vc). We conclude that differential activation of MAPKs and glial cells in the rostral subdivisions of the TSNC as well as the Vc may have a substantial role in the pathogenesis of neuropathic pain following trigeminal nerve injury. PMID:21087641

Terayama, Ryuji; Fujisawa, Naoko; Yamaguchi, Daisuke; Omura, Shinji; Ichikawa, Hiroyuki; Sugimoto, Tomosada

2011-02-01

215

Dexamethasone Enhanced Functional Recovery after Sciatic Nerve Crush Injury in Rats  

PubMed Central

Dexamethasone is currently used for the treatment of peripheral nerve injury, but its mechanisms of action are not completely understood. Inflammation/immune response at the site of nerve lesion is known to be an essential trigger of the pathological changes that have a critical impact on nerve repair and regeneration. In this study, we observed the effects of various doses of dexamethasone on the functional recovery after sciatic nerve crush injury in a rat model. Motor functional recovery was monitored by walking track analysis and gastrocnemius muscle mass ratio. The myelinated axon number was counted by morphometric analysis. Rats administered dexamethasone by local intramuscular injection had a higher nerve function index value, increased gastrocnemius muscle mass ratio, reduced Wallerian degeneration severity, and enhanced regenerated myelinated nerve fibers. Immunohistochemical analysis was performed for CD3 expression, which is a marker for T-cell activation, and infiltration in the sciatic nerve. Dexamethasone-injected rats had fewer CD3-positive cells compared to controls. Furthermore, we found increased expression of GAP-43, which is a factor associated with development and plasticity of the nervous system, in rat nerves receiving dexamethasone. These results provide strong evidence that dexamethasone enhances sciatic nerve regeneration and function recovery in a rat model of sciatic nerve injury through immunosuppressive and potential neurotrophic effects.

Feng, Xinhong; Yuan, Wei

2015-01-01

216

Preserved sensory-motor function despite large-scale morphological alterations in a series of patients with holocord syringomyelia.  

PubMed

Although the central nervous system has a limited capacity for regeneration after acute brain and spinal cord injuries, it can reveal extensive morphological changes. Occasionally, the formation of an extensive syrinx in the spinal cord can be observed that causes no or only limited signs of functional impairment. This condition creates a unique opportunity to evaluate the mismatch between substantial morphological changes and functional outcomes. We identified seven patients with holocord syringomyelia affecting the cervical cord following chronic traumatic thoracic/lumbar spinal cord injury (19-34 years after injury) or holocord syringomyelia of non-traumatic origin, and anatomical syrinx dimensions (length, cross-sectional area) were determined using sagittal and axial magnetic resonance imaging scans. Motor- and sensory-pathway integrity were evaluated using electrophysiological assessments (i.e., motor, dermatomal sensory, and dermatomal contact-heat [dCHEP] evoked potentials, as well as nerve conduction studies). These were specifically compared to clinical measures of upper-limb strength and grasping performance, including three-dimensional motion analysis. Despite extensive anatomical changes of the cervical cord (on average 26% reduction of residual spinal cord area and intrusion of almost the entire cervical spinal cord), a clinically relevant impairment of upper-limb motor function was absent while only subtle sensory deficits could be detected. dCHEPs revealed the highest sensitivity by disclosing impairments of spinothalamic pathways. Comparable to that of the brain, extensive anatomical changes of the spinal cord can occur with only subtle functional impairment. The time scale of slowly-emerging morphological alterations is essential to permit an enormous capacity for plasticity of the spinal cord. PMID:25219978

Awai, Lea; Curt, Armin

2015-03-15

217

Quantitative Evaluation of Median Nerve Motor Function in Carpal Tunnel Syndrome Using Load Cell : Correlation with Clinical, Electrodiagnostic, and Ultrasonographic Findings  

PubMed Central

Objective Major complaints of carpal tunnel syndrome (CTS) are sensory components. However, motor deficit also impedes functional status of hand. Contrary to evaluation of sensory function, the objective, quantitative evaluation of median nerve motor function is not easy. The motor function of median was evaluated quantitatively using load cell and its correlation with findings of electrodiagnostic study (EDS) was evaluated. Methods Objective motor function of median nerve was evaluated by load cell and personal computer-based measurement system. All of the measurement was done in patients diagnosed as having idiopathic CTS by clinical features and EDS findings. The strength of thumb abduction and index finger flexion was measured in each hand three times, and the average value was used to calculate thumb index ratio (TIR). The correlation of TIR with clinical, EDS, and ultrasonographic findings were evaluated. Results The TIR was evaluated in 67 patients (119 hands). There were 14 males and 53 females, mean age were 57.6 years (range 28 to 81). The higher preoperative nerve conductive studies grade of the patients, the lower TIR was observed [p<0.001, analysis of variance (ANOVA)]. TIR of cases with thenar atrophy were significantly lower than those without (p<0.001, t-test). TIR were significantly lower in patients with severe median nerve swelling in ultrasonography (p=0.042, ANOVA). Conclusion Measurements of median nerve motor function using load cell is a valuable evaluation tool in CTS. It might be helpful in detecting subclinical motor dysfunction before muscle atrophy develops. PMID:24278653

Kim, Dong Hwan; Park, Sung Bae; Lee, Sang Hyung; Son, Young-Je; Chung, Gih Sung

2013-01-01

218

Ipsilateral facial sensory and motor responses to basal fronto-temporal cortical stimulation: Evidence suggesting direct activation of cranial nerves  

Microsoft Academic Search

To clarify the generator mechanism of sensory and motor facial responses ipsilateral to electrical stimulation of the inferior fronto-temporal cortex in epilepsy patients. Out of 30 patients who have been evaluated with chronically implanted subdural electrodes for medically intractable partial seizure or brain tumor involving the basal frontal or temporal cortex, 4 patients (age ranging 24–57 years) showed sensory and

Tahamina Begum; Akio Ikeda; Masao Matsuhashi; Nobuhiro Mikuni; Susumu Miyamoto; Nobuo Hashimoto; Takashi Nagamine; Hidenao Fukuyama; Hiroshi Shibasaki

2006-01-01

219

Vascularization of the dorsal root ganglia and peripheral nerve of the mouse: Implications for chemical-induced peripheral sensory neuropathies  

Microsoft Academic Search

Although a variety of industrial chemicals, as well as several chemotherapeutic agents used to treat cancer or HIV, preferentially induce a peripheral sensory neuropathy what remains unclear is why these agents induce a sensory vs. a motor or mixed neuropathy. Previous studies have shown that the endothelial cells that vascularize the dorsal root ganglion (DRG), which houses the primary afferent

Juan M Jimenez-Andrade; Monica B Herrera; Joseph R Ghilardi; Marina Vardanyan; Ohannes K Melemedjian; Patrick W Mantyh

2008-01-01

220

VEGF-B selectively regenerates injured peripheral neurons and restores sensory and trophic functions  

PubMed Central

VEGF-B primarily provides neuroprotection and improves survival in CNS-derived neurons. However, its actions on the peripheral nervous system have been less characterized. We examined whether VEGF-B mediates peripheral nerve repair. We found that VEGF-B induced extensive neurite growth and branching in trigeminal ganglia neurons in a manner that required selective activation of transmembrane receptors and was distinct from VEGF-A–induced neuronal growth. VEGF-B–induced neurite elongation required PI3K and Notch signaling. In vivo, VEGF-B is required for normal nerve regeneration: mice lacking VEGF-B showed impaired nerve repair with concomitant impaired trophic function. VEGF-B treatment increased nerve regeneration, sensation recovery, and trophic functions of injured corneal peripheral nerves in VEGF-B–deficient and wild-type animals, without affecting uninjured nerves. These selective effects of VEGF-B on injured nerves and its lack of angiogenic activity makes VEGF-B a suitable therapeutic target to treat nerve injury. PMID:25404333

Guaiquil, Victor H.; Pan, Zan; Karagianni, Natalia; Fukuoka, Shima; Alegre, Gemstonn; Rosenblatt, Mark I.

2014-01-01

221

Enhanced release of adenosine in rat hind paw following spinal nerve ligation: involvement of capsaicin-sensitive sensory afferents  

Microsoft Academic Search

Modulation of endogenous adenosine levels by inhibition of adenosine metabolism produces a peripheral antinociceptive effect in a neuropathic pain model. The present study used microdialysis to investigate the neuronal mechanisms modulating extracellular adenosine levels in the rat hind paw following tight ligation of the L5 and L6 spinal nerves. Subcutaneous injection of 50 ?l saline into the nerve-injured paw induced

X. J Liu; T. D White; J Sawynok

2002-01-01

222

TRPA1 receptor localisation in the human peripheral nervous system and functional studies in cultured human and rat sensory neurons  

Microsoft Academic Search

TRPA1 is a receptor expressed by sensory neurons, that is activated by low temperature (<17°C) and plant derivatives such as cinnamaldehyde and isoeugenol, to elicit sensations including pain. Using immunohistochemistry, we have, for the first time, localised TRPA1 in human DRG neurons, spinal cord motoneurones and nerve roots, peripheral nerves, intestinal myenteric plexus neurones, and skin basal keratinocytes. TRPA1 co-localised

U. Anand; W. R. Otto; P. Facer; N. Zebda; I. Selmer; M. J. Gunthorpe; I. P. Chessell; M. Sinisi; R. Birch; P. Anand

2008-01-01

223

Electrical Stimulation as a Therapeutic Option to Improve Eyelid Function in Chronic Facial Nerve Disorders  

Microsoft Academic Search

PURPOSE. TO establish whether it is possible to improve orbicularis oculi muscle function in the eyelids of patients with a chronic seventh cranial nerve palsy by using transcutaneous electrical stimulation to the point at which electrical stimulation induces a functional blink. METHODS. Ten subjects (one woman, nine men) aged 36 to 76 with chronic, moderate to severe facial nerve palsy

John Gittins; Kevin Martin; James Sbeldrick; Ashwin Reddy; Leonard Tbean

224

Sensory fusion in Physarum polycephalum and implementing multi-sensory functional computation.  

PubMed

Surface electrical potential and observational growth recordings were made of a protoplasmic tube of the slime mould Physarum polycephalum in response to a multitude of stimuli with regards to sensory fusion or multisensory integration. Each stimulus was tested alone and in combination in order to evaluate for the first time the effect that multiple stimuli have on the frequency of streaming oscillation. White light caused a decrease in frequency whilst increasing the temperature and applying a food source in the form of oat flakes both increased the frequency. Simultaneously stimulating P. polycephalum with light and oat flake produced no net change in frequency, while combined light and heat stimuli showed an increase in frequency smaller than that observed for heat alone. When the two positive stimuli, oat flakes and heat, were combined, there was a net increase in frequency similar to the cumulative increases caused by the individual stimuli. Boolean logic gates were derived from the measured frequency change. PMID:24695059

Whiting, James G H; de Lacy Costello, Ben P J; Adamatzky, Andrew

2014-05-01

225

Nerve Growth Factor Mediates a Switch in Intracellular Signaling for PGE2-Induced Sensitization of Sensory Neurons from Protein Kinase A to Epac  

PubMed Central

We examined whether nerve growth factor (NGF), an inflammatory mediator that contributes to chronic hypersensitivity, alters the intracellular signaling that mediates the sensitizing actions of PGE2 from activation of protein kinase A (PKA) to exchange proteins directly activated by cAMP (Epacs). When isolated sensory neurons are grown in the absence of added NGF, but not in cultures grown with 30 ng/ml NGF, inhibiting protein kinase A (PKA) activity blocks the ability of PGE2 to augment capsaicin-evoked release of the neuropeptide CGRP and to increase the number of action potentials (APs) evoked by a ramp of current. Growing sensory neurons in culture in the presence of increasing concentrations of NGF increases the expression of Epac2, but not Epac1. An intradermal injection of complete Freund's adjuvant into the rat hindpaw also increases the expression of Epac2, but not Epac1 in the dorsal root ganglia and spinal cord: an effect blocked by intraplantar administration of NGF antibodies. Treating cultures grown in the presence of 30 ng/ml NGF with Epac1siRNA significantly reduced the expression of Epac1, but not Epac2, and did not block the ability of PGE2 to augment capsaicin-evoked release of CGRP from sensory neurons. Exposing neuronal cultures grown in NGF to Epac2siRNAreduced the expression of Epac2, but not Epac1 and prevented the PGE2-induced augmentation of capsaicin and potassium-evoked CGRP release in sensory neurons and the PGE2-induced increase in the number of APs generated by a ramp of current. In neurons grown with no added NGF, Epac siRNAs did not attenuate PGE2-induced sensitization. These results demonstrate that NGF, through increasing Epac2 expression, alters the signaling cascade that mediates PGE2-induced sensitization of sensory neurons, thus providing a novel mechanism for maintaining PGE2-induced hypersensitivity during inflammation. PMID:25126967

Vasko, Michael R.; Habashy Malty, Ramy; Guo, Chunlu; Duarte, Djane B.; Zhang, Yihong; Nicol, Grant D.

2014-01-01

226

Analysis of osm-6, a gene that affects sensory cilium structure and sensory neuron function in Caenorhabditis elegans.  

PubMed Central

Mutation in the Caenorhabditis elegans gene osm-6 was previously shown to result in defects in the ultrastructure of sensory cilia and defects in chemosensory and mechanosensory behaviors. We have cloned osm-6 by transposon tagging and transformation rescue and have identified molecular lesions associated with five osm-6 mutations. The osm-6 gene encodes a protein that is 40% identical in amino acid sequence to a predicted mammalian protein of unknown function. We fused osm-6 with the gene for green fluorescent protein (GFP); the fusion gene rescued the osm-6 mutant phenotype and showed accumulation of GFP in ciliated sensory neurons exclusively. The OSM-6::GFP protein was localized to cytoplasm, including processes and dendritic endings where sensory cilia are situated. Mutations in other genes known to cause ciliary defects led to changes in the appearance of OSM-6::GFP in dendritic endings or, in the case of daf-19, reduced OSM-6::GFP accumulation. We conclude from an analysis of genetic mosaics that osm-6 acts cell autonomously in affecting cilium structure. PMID:9475731

Collet, J; Spike, C A; Lundquist, E A; Shaw, J E; Herman, R K

1998-01-01

227

A controlled trial of the retraining of the sensory function of the hand in stroke patients.  

PubMed Central

A controlled trial of retraining of the sensory function of the hand was undertaken in hemiplegic patients after the period of spontaneous recovery. Twenty hemiplegic patients with sensory deficit in the hand, two or more years after stroke, received systematic retraining three times a week for six weeks. Sensation in the plegic hand was tested before and after this period in these patients and in 19 untreated control patients. The treated group showed large and significant gains on all sensory tests (P < 0.001), while no change occurred in the control group. It is concluded that somatosensory deficit can be alleviated even years after stroke and that rehabilitation for stroke patients should include sensory retraining for those with sensory deficit. PMID:8459238

Yekutiel, M; Guttman, E

1993-01-01

228

A (heat) shock to the system promotes peripheral nerve regeneration  

PubMed Central

Peripheral nerves are easily damaged, resulting in loss of motor and sensory function. Recovery of motor and sensory function after peripheral nerve injury is suboptimal, even after appropriate surgical repair. This is due to the slow rate of axonal elongation during regeneration and atrophic changes that occur in denervated Schwann cells and target muscle with proximal lesions. One way to solve this problem is to accelerate the rate at which the axons regenerate. In this issue of the JCI, Ma and colleagues show that this can be achieved in mice by overexpression of heat shock protein 27, providing hope for enhanced functional recovery in patients after peripheral nerve damage. PMID:21965324

Höke, Ahmet

2011-01-01

229

Fluorescently Labeled Peptide Increases Identification of Degenerated Facial Nerve Branches during Surgery and Improves Functional Outcome  

PubMed Central

Nerve degeneration after transection injury decreases intraoperative visibility under white light (WL), complicating surgical repair. We show here that the use of fluorescently labeled nerve binding probe (F-NP41) can improve intraoperative visualization of chronically (up to 9 months) denervated nerves. In a mouse model for the repair of chronically denervated facial nerves, the intraoperative use of fluorescent labeling decreased time to nerve identification by 40% compared to surgeries performed under WL alone. Cumulative functional post-operative recovery was also significantly improved in the fluorescence guided group as determined by quantitatively tracking of the recovery of whisker movement at time intervals for 6 weeks post-repair. To our knowledge, this is the first description of an injectable probe that increases visibility of chronically denervated nerves during surgical repair in live animals. Future translation of this probe may improve functional outcome for patients with chronic denervation undergoing surgical repair. PMID:25751149

Hussain, Timon; Mastrodimos, Melina B.; Raju, Sharat C.; Glasgow, Heather L.; Whitney, Michael; Friedman, Beth; Moore, Jeffrey D.; Kleinfeld, David; Steinbach, Paul; Messer, Karen; Pu, Minya; Tsien, Roger Y.; Nguyen, Quyen T.

2015-01-01

230

Novel Roles for Osteopontin and Clusterin in Peripheral Motor and Sensory Axon Regeneration  

PubMed Central

Previous studies demonstrated that Schwann cells (SCs) express distinct motor and sensory phenotypes, which impact the ability of these pathways to selectively support regenerating neurons. In the present study, unbiased microarray analysis was used to examine differential gene expression in denervated motor and sensory pathways in rats. Several genes that were significantly upregulated in either denervated sensory or motor pathways were identified and two secreted factors were selected for further analysis: osteopontin (OPN) and clusterin (CLU) which were upregulated in denervated motor and sensory pathways, respectively. Sciatic nerve transection induced upregulation of OPN and CLU and expression of both returned to baseline levels with ensuing regeneration. In vitro analysis using exogenously applied OPN induced outgrowth of motor but not sensory neurons. CLU, however, induced outgrowth of sensory neurons, but not motor neurons. To assess the functional importance of OPN and CLU, peripheral nerve regeneration was examined in OPN and CLU?/? mice. When compared with OPN+/+ mice, motor neuron regeneration was reduced in OPN?/? mice. Impaired regeneration through OPN?/? peripheral nerves grafted into OPN+/+ mice indicated that loss of OPN in SCs was responsible for reduced motor regeneration. Sensory neuron regeneration was impaired in CLU?/? mice following sciatic nerve crush and impaired regeneration nerve fibers through CLU?/? nerve grafts transplanted into CLU+/+ mice indicated that reduced sensory regeneration is likely due to SC-derived CLU. Together, these studies suggest unique roles for SC-derived OPN and CLU in regeneration of peripheral motor and sensory axons. PMID:24478351

Mi, Ruifa; Connor, Emmalynn; Reed, Nicole; Vyas, Alka; Alspalter, Manula; Coppola, Giovanni; Geschwind, Daniel H.; Brushart, Thomas M.

2014-01-01

231

Methods to evaluate functional nerve recovery in adult rats: walking track analysis, video analysis and the withdrawal reflex  

Microsoft Academic Search

The aim of this study was to compare different methods for the evaluation of functional nerve recovery. Three groups of adult male Wistar rats were studied. In group A, a 12-mm gap between nerve ends was bridged by an autologous nerve graft; in rats of group B we performed a crush lesion of the sciatic nerve and group C consisted

Jeroen R. Dijkstra; Marcel F. Meek; Peter H. Robinson; Albert Gramsbergen

2000-01-01

232

Clinical nerve conduction and needle electromyography studies.  

PubMed

The electrodiagnostic study, consisting of nerve conduction studies and needle electromyography, is a useful adjunct to the clinical examination of the peripheral nervous system. The three types of nerve conduction study are motor, sensory, and mixed, of which motor is the least sensitive. Electromyography records the intrinsic electrical activity of muscle fibers, thus providing the physiologic status of muscle function. To interpret the electrodiagnostic study results, the clinician must understand the anatomic and physiologic basis of the studies. Peripheral nerve entrapment initially results in focal demyelination; thus, nerve conduction velocity slows across the site. However, with radiculopathy and nerve root compression, the nerve conduction study may be normal. Both nerve trauma and polyneuropathy show marked differences in their effect on the results of electrodiagnostic studies. PMID:15473679

Lee, Donald H; Claussen, Gwendolyn C; Oh, Shin

2004-01-01

233

Etifoxine improves peripheral nerve regeneration and functional recovery  

Microsoft Academic Search

Peripheral nerves show spontaneous regenerative responses, but recovery after injury or peripheral neuropathies (toxic, diabetic, or chronic inflammatory demyelinating polyneuropathy syndromes) is slow and often incomplete, and at present no efficient treatment is available. Using well-defined peripheral nerve lesion paradigms, we assessed the therapeutic usefulness of etifoxine, recently identified as a ligand of the translocator protein (18 kDa) (TSPO), to

Christelle Girard; Song Liu; Françoise Cadepond; David Adams; Catherine Lacroix; Marc Verleye; Jean-Marie Gillardin; Etienne-Emile Baulieu; Michael Schumacher; Ghislaine Schweizer-Groyer

2008-01-01

234

Sensory deficits of a nerve root lesion can be objectively documented by somatosensory evoked potentials elicited by painful infrared laser stimulations: a case study.  

PubMed Central

Somatosensory evoked potentials (SEPs) in response to painful laser stimuli were measured in a patient with a unilateral sensory deficit due to radiculopathy at cervical levels C7 and C8. Laser evoked potentials (LEPs) were compared with SEPs using standard electrical stimulation of median and ulnar nerves at the wrist and mechanical stimulation of the fingertips by means of a mechanical stimulator. Early and late ulnar and median nerve SEPs were normal. Mechanical stimulation resulted in w shaped early SEPs from all five fingertips with some degree of abnormality at the fourth and fifth digits of the affected hand. Late LEPs were completely absent for stimulations at affected dermatomes and normal in the unaffected control dermatomes. The border between skin areas with normal or absent LEPs was very sharp and fitted the dermatomes of intact C6 and damaged C7 and C8 nerve roots. It is suggested that pain dermatomes are narrower than tactile dermatomes because thin fibres of the nociceptive system, activated by laser stimuli, probably do not overlap between adjacent spinal segments to the same extent as thick fibres of the mechanoreceptive system, activated by standard electrical or mechanical stimulation. Images PMID:8676136

Lorenz, J; Hansen, H C; Kunze, K; Bromm, B

1996-01-01

235

Genetic inactivation and pharmacological blockade of sigma-1 receptors prevent paclitaxel-induced sensory-nerve mitochondrial abnormalities and neuropathic pain in mice  

PubMed Central

Background Paclitaxel, a widely-used antineoplastic drug, produces a painful peripheral neuropathy that in rodents is associated with peripheral-nerve mitochondrial alterations. The sigma-1 receptor (?1R) is a ligand-regulated molecular chaperone involved in mitochondrial calcium homeostasis and pain hypersensitivity. This receptor plays a key role in paclitaxel-induced neuropathic pain, but it is not known whether it also modulates mitochondrial abnormalities. In this study, we used a mouse model of paclitaxel-induced neuropathic pain to test the involvement of the ?1R in the mitochondrial abnormalities associated with paclitaxel, by using genetic (?1R knockout mice) and pharmacological (?1R antagonist) approaches. Results Paclitaxel administration to wild-type (WT) mice produced cold- and mechanical-allodynia, and an increase in the frequency of swollen and vacuolated mitochondria in myelinated A-fibers, but not in C-fibers, of the saphenous nerve. Behavioral and mitochondrial alterations were marked at 10 days after paclitaxel-administration and had resolved at day 28. In contrast, paclitaxel treatment did not induce allodynia or mitochondrial abnormalities in ?1R knockout mice. Moreover, the prophylactic treatment of WT mice with BD-1063 also prevented the neuropathic pain and mitochondrial abnormalities induced by paclitaxel. Conclusions These results suggest that activation of the ?1R is necessary for development of the sensory nerve mitochondrial damage and neuropathic pain produced by paclitaxel. Therefore, ?1R antagonists might have therapeutic value for the prevention of paclitaxel-induced neuropathy. PMID:24517272

2014-01-01

236

Functional outcome of nerve transfer for restoration of shoulder and elbow function in upper brachial plexus injury  

Microsoft Academic Search

BACKGROUND: Purpose of this study was to evaluate the functional outcome of spinal accessory to suprascapular nerve transfer (XI-SSN) done for restoration of shoulder function and partial transfer of ulnar nerve to the motor branch to the biceps muscle for the recovery of elbow flexion (Oberlin transfer). METHODS: This is a prospective study involving 15 consecutive cases of upper plexus

Hari Venkatramani; Praveen Bhardwaj; Sajedur Reza Faruquee; S Raja Sabapathy

2008-01-01

237

Proprioceptive sensory function in Parkinson's disease and Huntington's disease: evidence from proprioception-related EEG potentials  

Microsoft Academic Search

.   In both Parkinson's disease and Huntington's disease, proprioceptive sensory deficits have been suggested to contribute to\\u000a the motor manifestations of the disease. Here, proprioceptive sensory function was investigated in Parkinson's disease patients,\\u000a Huntington's disease patients, and healthy control subjects (each group n=8), using proprioception-related evoked potentials. Proprioception-related potentials were elicited by passive index finger\\u000a movements and measured with high-density

E. Seiss; P. Praamstra; C. W. Hesse; H. Rickards

2003-01-01

238

Restoration of visual function following optic nerve regeneration in bluegill ~Lepomis macrochirus!  

E-print Network

Restoration of visual function following optic nerve regeneration in bluegill ~Lepomis macrochirus ~Lepomis macrochirus! pumpkinseed ~Lepomis gibbosus! hybrid sunfish. Regenerating optic nerve axons! pumpkinseed ~Lepomis gibbosus! hybrid sunfish MICHAEL P. CALLAHAN1,2 and ALLEN F. MENSINGER1 1 Department

Mensinger, Allen F.

239

Oxidation of a potassium channel causes progressive sensory function loss during aging  

Microsoft Academic Search

Potassium channels are key regulators of neuronal excitability. Here we show that oxidation of the K+ channel KVS-1 during aging causes sensory function loss in Caenorhabditis elegans and that protection of this channel from oxidation preserves neuronal function. Chemotaxis, a function controlled by KVS-1, was significantly impaired in worms exposed to oxidizing agents, but only moderately affected in worms harboring

Shi-Qing Cai; Federico Sesti

2009-01-01

240

The Trigeminal (V) and Facial (VII) Cranial Nerves  

PubMed Central

There are close functional and anatomical relationships between cranial nerves V and VII in both their sensory and motor divisions. Sensation on the face is innervated by the trigeminal nerves (V) as are the muscles of mastication, but the muscles of facial expression are innervated mainly by the facial nerve (VII) as is the sensation of taste. This article briefly reviews the anatomy of these cranial nerves, disorders of these nerves that are of particular importance to psychiatry, and some considerations for differential diagnosis. PMID:20386632

Sanders, Richard D.

2010-01-01

241

Clinical strategies to enhance nerve regeneration in composite tissue allotransplantation.  

PubMed

Reinnervation of a hand transplant ultimately dictates functional recovery but provides a significant regenerative challenge. This article highlights interventions to enhance nerve regeneration through acceleration of axonal regeneration or augmentation of Schwann cell support and discuss their relevance to composite tissue allotransplantation. Surgical techniques that may be performed at the time of transplantation to optimize intrinsic muscle recovery--including appropriate alignment of ulnar nerve motor and sensory components, transfer of the distal anterior interosseous nerve to the recurrent motor branch of the median nerve, and prophylactic release of potential nerve entrapment points--are also presented. PMID:22051390

Glaus, Simone W; Johnson, Philip J; Mackinnon, Susan E

2011-11-01

242

Sensory Functions for Degenerin/Epithelial Sodium Channels (DEG/ENaC)  

PubMed Central

All animals use a sophisticated array of receptor proteins to sense their external and internal environments. Major advances have been made in recent years in understanding the molecular and genetic bases for sensory transduction in diverse modalities, indicating that both metabotropic and ionotropic pathways are important in sensory functions. Here, I review the historical background and recent advances in understanding the roles of a relatively newly discovered family of receptors, the degenerin/epithelial sodium channels (DEG/ENaC). These animal-specific cation channels show a remarkable sequence and functional diversity in different species and seem to exert their functions in diverse sensory modalities. Functions for DEG/ENaC channels have been implicated in mechanosensation as well as chemosensory transduction pathways. In spite of overall sequence diversity, all family members share a unique protein topology that includes just two transmembrane domains and an unusually large and highly structured extracellular domain, that seem to be essential for both their mechanical and chemical sensory functions. This review will discuss many of the recent discoveries and controversies associated with sensory function of DEG/ENaC channels in both vertebrate and invertebrate model systems, covering the role of family members in taste, mechanosensation, and pain. PMID:22099690

Ben-Shahar, Yehuda

2012-01-01

243

Comparison of the sensory threshold in healthy human volunteers with the sensory nerve response of the rat in vitro hindlimb skin and saphenous nerve preparation on cutaneous electrical stimulation  

Microsoft Academic Search

We report a comparative study of stimulation thresholds of cutaneous fibres of the rat in vitro skin and saphenous nerve preparation with psychophysical measurements of sensibility to cutaneous electrical stimulation in human volunteers. The same clinical diagnostic stimulator and modified skin electrodes were used in both animal and human experiments. Axons were recruited by increasing the stimulus strength, and correlation

R. M. R. McAllister; L. A. Urban; A. Dray; P. J. Smith

1995-01-01

244

Sport-Related Concussion and Sensory Function in Young Adults  

PubMed Central

Context: The long-term implications of concussive injuries for brain and cognitive health represent a growing concern in the public consciousness. As such, identifying measures sensitive to the subtle yet persistent effects of concussive injuries is warranted. Objective: To investigate how concussion sustained early in life influences visual processing in young adults. We predicted that young adults with a history of concussion would show decreased sensory processing, as noted by a reduction in P1 event-related potential component amplitude. Design: Cross-sectional study. Setting: Research laboratory. Patients or Other Participants: Thirty-six adults (18 with a history of concussion, 18 controls) between the ages of 20 and 28 years completed a pattern-reversal visual evoked potential task while event-related potentials were recorded. Main Outcome Measure(s): The groups did not differ in any demographic variables (all P values > .05), yet those with a concussive history exhibited reduced P1 amplitude compared with the control participants (P = .05). Conclusions: These results suggest that concussion history has a negative effect on visual processing in young adults. Further, upper-level neurocognitive deficits associated with concussion may, in part, result from less efficient downstream sensory capture. PMID:24377961

Moore, Robert D.; Broglio, Steven P.; Hillman, Charles H.

2014-01-01

245

Insect sensory systems inspired computing and communications  

Microsoft Academic Search

Insects are the most successful group of living things in terms of the number of species, the biomass and their distribution. Entomological research has revealed that the insect sensory systems are crucial for their success. Compared to human brains, the insect central nerve systems are extremely primitive and simple, both structurally and functionally, and are of minimal learning ability. Faced

Axel W. Krings

2009-01-01

246

A Silicon Model of Auditory-Nerve Response Nonlinear signal processing is an integral part of sensory transduction in  

E-print Network

5 Chapter 2 A Silicon Model of Auditory-Nerve Response Nonlinear signal processing is an integral and operation of an integrated circuit that models, to a limited degree, the evoked responses of the auditory published in (Lazzaro and Mead, 1989b). 2.1 Neural Architecture of the Cochlea Both mechanical

Lazzaro, John

247

Concordance between epidermal nerve fiber density and sensory examination in patients with symptoms of idiopathic small fiber neuropathy  

Microsoft Academic Search

Quantitation of epidermal nerve fiber (ENF) density is an objective diagnostic test of small fiber neuropathy (SFN). For a diagnostic test to be clinically useful it should correspond well with clinically meaningful physical findings. We performed a retrospective analysis of the concordance between foot ENF density and clinical findings in all patients seen at our institution with possible idiopathic SFN

David Walk; Gwen Wendelschafer-Crabb; Cynthia Davey; William R. Kennedy

2007-01-01

248

Altered rectal sensory response induced by balloon distention in patients with functional abdominal pain syndrome  

Microsoft Academic Search

BACKGROUND: Functional abdominal pain syndrome (FAPS) has chronic unexplained abdominal pain and is similar to the psychiatric diagnosis of somatoform pain disorder. A patient with irritable bowel syndrome (IBS) also has chronic unexplained abdominal pain, and rectal hypersensitivity is observed in a majority of the patients. However, no reports have evaluated the visceral sensory function of FAPS precisely. We aimed

Tsukasa Nozu; Miwako Kudaira

2009-01-01

249

Anatomical relations of the superficial sensory branches of the radial nerve: a cadaveric study with clinical implications  

PubMed Central

Background Anatomically, it is difficult to give a systematic description of the superficial branch of the radial nerve (SBRN). Our aim was to describe the exact relationship of the SBRN to fixed bony points of radial styloid and Lister's tubercle, and to the cephalic vein. We also compared our data with other international studies. Methods The study was a descriptive anatomical study. Twenty-five forearms were dissected. Measurements were made from predefined fixed reference points. Results The mean distance to the point of emergence of the nerve from the radial styloid was 8.54 cm (SD = 1.32). The nerve branched at a mean distance of 5.57 cm (SD = 1.43) from the radial styloid. The mean distance to the point where the most medial and most lateral branches of the nerve crossing the wrist joint, measured from the Lister's tubercle were 2.51 cm (SD = 0.53) and 3.90 cm (SD = 0.64). In 17 specimens(68%) cephalic vein crossed the SBRN superficially once. Mean distance from the radial styloid to the most distal point where the vein crossed the nerve was 5.10 cm. Diffefrence between mean distance to the point of emergence and branching point, when compared with other international studies were not statistically significant. (P value > 0.05) Conclusions We recommend avoiding transverse incisions in the snuffbox region between 2.51 cm and 3.90 cm from the Listers tubercle. We also recommend avoiding cannulation of the cephalic vein in the distal forearm. PMID:22054296

2011-01-01

250

Localized and Sustained Delivery of Erythropoietin from PLGA Microspheres Promotes Functional Recovery and Nerve Regeneration in Peripheral Nerve Injury  

PubMed Central

Erythropoietin (EPO) has been demonstrated to exert neuroprotective effects on peripheral nerve injury recovery. Though daily intraperitoneal injection of EPO during a long period of time was effective, it was a tedious procedure. In addition, only limited amount of EPO could reach the injury sites by general administration, and free EPO is easily degraded in vivo. In this study, we encapsulated EPO in poly(lactide-co-glycolide) (PLGA) microspheres. Both in vitro and in vivo release assays showed that the EPO-PLGA microspheres allowed sustained release of EPO within a period of two weeks. After administration of such EPO-PLGA microspheres, the peripheral nerve injured rats had significantly better recovery compared with those which received daily intraperitoneal injection of EPO, empty PLGA microspheres, or saline treatments. This was supported by the functional, electrophysiological, and histological evaluations of the recovery done at week 8 postoperatively. We conclude that sustained delivery of EPO could be achieved by using EPO-PLGA microspheres, and such delivery method could further enhance the recovery function of EPO in nerve injury recovery.

Zhang, Wei; Gao, Yuan; Zhou, Yan; Liu, Jianheng; Zhang, Licheng; Long, Anhua; Zhang, Lihai; Tang, Peifu

2015-01-01

251

A bioengineered peripheral nerve construct using aligned peptide amphiphile nanofibers.  

PubMed

Peripheral nerve injuries can result in lifelong disability. Primary coaptation is the treatment of choice when the gap between transected nerve ends is short. Long nerve gaps seen in more complex injuries often require autologous nerve grafts or nerve conduits implemented into the repair. Nerve grafts, however, cause morbidity and functional loss at donor sites, which are limited in number. Nerve conduits, in turn, lack an internal scaffold to support and guide axonal regeneration, resulting in decreased efficacy over longer nerve gap lengths. By comparison, peptide amphiphiles (PAs) are molecules that can self-assemble into nanofibers, which can be aligned to mimic the native architecture of peripheral nerve. As such, they represent a potential substrate for use in a bioengineered nerve graft substitute. To examine this, we cultured Schwann cells with bioactive PAs (RGDS-PA, IKVAV-PA) to determine their ability to attach to and proliferate within the biomaterial. Next, we devised a PA construct for use in a peripheral nerve critical sized defect model. Rat sciatic nerve defects were created and reconstructed with autologous nerve, PLGA conduits filled with various forms of aligned PAs, or left unrepaired. Motor and sensory recovery were determined and compared among groups. Our results demonstrate that Schwann cells are able to adhere to and proliferate in aligned PA gels, with greater efficacy in bioactive PAs compared to the backbone-PA alone. In vivo testing revealed recovery of motor and sensory function in animals treated with conduit/PA constructs comparable to animals treated with autologous nerve grafts. Functional recovery in conduit/PA and autologous graft groups was significantly faster than in animals treated with empty PLGA conduits. Histological examinations also demonstrated increased axonal and Schwann cell regeneration within the reconstructed nerve gap in animals treated with conduit/PA constructs. These results indicate that PA nanofibers may represent a promising biomaterial for use in bioengineered peripheral nerve repair. PMID:25064803

Li, Andrew; Hokugo, Akishige; Yalom, Anisa; Berns, Eric J; Stephanopoulos, Nicholas; McClendon, Mark T; Segovia, Luis A; Spigelman, Igor; Stupp, Samuel I; Jarrahy, Reza

2014-10-01

252

Improved gold chloride staining method for anatomical analysis of sensory nerve endings in the shoulder capsule and labrum as examples of loose and dense fibrous tissues.  

PubMed

Consistency in gold chloride staining is essential for anatomical analysis of sensory nerve endings. The gold chloride stain for this purpose has been modified by many investigators, but often yields inconsistent staining, which makes it difficult to differentiate structures and to determine nerve ending distribution in large tissue samples. We introduce additional steps and major changes to the modified Gairns' protocol. We controlled the temperature and mixing rate during tissue staining to achieve consistent staining and complete solution penetration. We subjected samples to sucrose dehydration to improve cutting efficiency. We then exposed samples to a solution containing lemon juice, formic acid and paraformaldehyde to produce optimal tissue transparency with minimal tissue deformity. We extended the time for gold chloride impregnation 1.5 fold. Gold chloride was reduced in the labrum using 25% formic acid in water for 18 h and in the capsule using 25% formic acid in citrate phosphate buffer for 2 h. Citrate binds gold nanoparticles, which minimizes aggregation in the tissue. We stored samples in fresh ultrapure water at 4° C to slow reduction and to maintain color contrast in the tissue. Tissue samples were embedded in Tissue Tek and sectioned at 80 and 100 ?m instead of using glycerin and teasing the tissue apart as in Gairns' modified gold chloride method. We attached sections directly to gelatin subbed slides after sectioning with a cryostat. The slides then were processed and coverslipped with Permount. Staining consistency was demonstrated throughout the tissue sections and neural structures were clearly identifiable. PMID:24476562

Witherspoon, J W; Smirnova, I V; McIff, T E

2014-07-01

253

Differential upregulation in DRG neurons of an ?2?-1 splice variant with a lower affinity for gabapentin after peripheral sensory nerve injury  

PubMed Central

The ?2?-1 protein is an auxiliary subunit of voltage-gated calcium channels, critical for neurotransmitter release. It is upregulated in dorsal root ganglion (DRG) neurons following sensory nerve injury, and is also the therapeutic target of the gabapentinoid drugs, which are efficacious in both experimental and human neuropathic pain conditions. ?2?-1 has 3 spliced regions: A, B, and C. A and C are cassette exons, whereas B is introduced via an alternative 3? splice acceptor site. Here we have examined the presence of ?2?-1 splice variants in DRG neurons, and have found that although the main ?2?-1 splice variant in DRG is the same as that in brain (?2?-1 ?A+B+C), there is also another ?2?-1 splice variant (?A+B?C), which is expressed in DRG neurons and is differentially upregulated compared to the main DRG splice variant ?2?-1 ?A+B+C following spinal nerve ligation. Furthermore, this differential upregulation occurs preferentially in a small nonmyelinated DRG neuron fraction, obtained by density gradient separation. The ?2?-1 ?A+B?C splice variant supports CaV2 calcium currents with unaltered properties compared to ?2?-1 ?A+B+C, but shows a significantly reduced affinity for gabapentin. This variant could therefore play a role in determining the efficacy of gabapentin in neuropathic pain. PMID:24315988

Lana, Beatrice; Schlick, Bettina; Martin, Stuart; Pratt, Wendy S.; Page, Karen M.; Goncalves, Leonor; Rahman, Wahida; Dickenson, Anthony H.; Bauer, Claudia S.; Dolphin, Annette C.

2014-01-01

254

Differential upregulation in DRG neurons of an ?2?-1 splice variant with a lower affinity for gabapentin after peripheral sensory nerve injury.  

PubMed

The ?2?-1 protein is an auxiliary subunit of voltage-gated calcium channels, critical for neurotransmitter release. It is upregulated in dorsal root ganglion (DRG) neurons following sensory nerve injury, and is also the therapeutic target of the gabapentinoid drugs, which are efficacious in both experimental and human neuropathic pain conditions. ?2?-1 has 3 spliced regions: A, B, and C. A and C are cassette exons, whereas B is introduced via an alternative 3' splice acceptor site. Here we have examined the presence of ?2?-1 splice variants in DRG neurons, and have found that although the main ?2?-1 splice variant in DRG is the same as that in brain (?2?-1 ?A+B+C), there is also another ?2?-1 splice variant (?A+B?C), which is expressed in DRG neurons and is differentially upregulated compared to the main DRG splice variant ?2?-1 ?A+B+C following spinal nerve ligation. Furthermore, this differential upregulation occurs preferentially in a small nonmyelinated DRG neuron fraction, obtained by density gradient separation. The ?2?-1 ?A+B?C splice variant supports CaV2 calcium currents with unaltered properties compared to ?2?-1 ?A+B+C, but shows a significantly reduced affinity for gabapentin. This variant could therefore play a role in determining the efficacy of gabapentin in neuropathic pain. PMID:24315988

Lana, Beatrice; Schlick, Bettina; Martin, Stuart; Pratt, Wendy S; Page, Karen M; Goncalves, Leonor; Rahman, Wahida; Dickenson, Anthony H; Bauer, Claudia S; Dolphin, Annette C

2014-03-01

255

Spontaneous intraneural hematoma of the sural nerve.  

PubMed

Symptomatic intraneural hemorrhage occurs rarely. It presents with pain and/or weakness in the distribution following the anatomic innervation pattern of the involved nerve. When a purely sensory nerve is affected, the symptoms can be subtle. We present a previously healthy 36-year-old female who developed an atraumatic, spontaneous intraneural hematoma of her sural nerve. Sural dysfunction was elicited from the patient's history and physical examination. The diagnosis was confirmed with magnetic resonance imaging, and surgical decompression provided successful resolution of her preoperative symptoms. To our knowledge, this entity has not been reported previously. Our case highlights the importance of having a high index of suspicion for nerve injury or compression in patients whose complaints follow a typical peripheral nerve distribution. Prior studies have shown that the formation of intraneural hematoma and associated compression of nerve fibers result in axonal degeneration, and surgical decompression decreases axonal degeneration and aids functional recovery. PMID:25311865

Richardson, Shawn S; McLawhorn, Alexander S; Mintz, Douglas N; DiCarlo, Edward F; Weiland, Andrew J

2015-04-01

256

Ketoprofen combined with artery graft entubulization improves functional recovery of transected peripheral nerves.  

PubMed

The objective was to assess the local effect of ketoprofen on sciatic nerve regeneration and functional recovery. Eighty healthy male white Wistar rats were randomized into four experimental groups of 20 animals each: In the transected group (TC), the left sciatic nerve was transected and nerve cut ends were fixed in the adjacent muscle. In the treatment group the defect was bridged using an artery graft (AG/Keto) filled with 10 microliter ketoprofen (0.1 mg/kg). In the artery graft group (AG), the graft was filled with phosphated-buffer saline alone. In the sham-operated group (SHAM), the sciatic nerve was exposed and manipulated. Each group was subdivided into four subgroups of five animals each and regenerated nerve fibres were studied at 4, 8, 12 and 16 weeks post operation. Behavioural testing, sciatic nerve functional study, gastrocnemius muscle mass and morphometric indices showed earlier regeneration of axons in AG/Keto than in AG group (p < 0.05). Immunohistochemical study clearly showed more positive location of reactions to S-100 in AG/Keto than in AG group. When loaded in an artery graft, ketoprofen improved functional recovery and morphometric indices of the sciatic nerve. Local usage of this easily accessible therapeutic medicine is cost saving and avoids the problems associated with systemic administration. PMID:23932540

Mohammadi, Rahim; Mehrtash, Moein; Nikonam, Nima; Mehrtash, Moied; Amini, Keyvan

2014-12-01

257

Activation of glia and microglial p38 MAPK in medullary dorsal horn contributes to tactile hypersensitivity following trigeminal sensory nerve injury.  

PubMed

Glial activation is known to contribute to pain hypersensitivity following spinal sensory nerve injury. In this study, we investigated mechanisms by which glial cell activation in medullary dorsal horn (MDH) would contribute to tactile hypersensitivity following inferior alveolar nerve and mental nerve transection (IAMNT). Activation of microglia and astrocytes was monitored at 2 h, 1, 3, 7, 14, 28, and 60 days using immunohistochemical analysis with OX-42 and GFAP antibodies, respectively. Tactile hypersensitivity was significantly increased at 1 day, and this lasted for 28 days after IAMNT. Microglial activation, primarily observed in the superficial laminae of MDH, was initiated at 1 day, maximal at 3 days, and maintained until 14 days after IAMNT. Astrocytic activation was delayed compared to that of microglia, being more profound at 7 and 14 days than at 3 days after IAMNT. Both tactile hypersensitivity and glial activation appeared to gradually reduce and then return to the basal level by 60 days after IAMNT. There was no significant loss of trigeminal ganglion neurons by 28 days following IAMNT, suggesting that degenerative changes in central terminals of primary afferents might not contribute to glial activation. Minocycline, an inhibitor of microglial activation, reduced microglial activation, inhibited p38 mitogen-activated protein kinase (MAPK) activation in microglia, and significantly attenuated the development of pain hypersensitivity in this model. These results suggest that glial activation in MDH plays an important role in the development of neuropathic pain and activation of p38 MAPK in hyperactive microglia contributes to pain hypersensitivity in IAMNT model. PMID:16495005

Piao, Zheng Gen; Cho, Ik-Hyun; Park, Chul Kyu; Hong, Jin Pyo; Choi, Se-Young; Lee, Sung Joong; Lee, Seungbok; Park, Kyungpyo; Kim, Joong Soo; Oh, Seog Bae

2006-04-01

258

Conventional and Functional MR Imaging of Peripheral Nerve Sheath Tumors: Initial Experience  

PubMed Central

BACKGROUND AND PURPOSE Differentiating benign from malignant peripheral nerve sheath tumors can be very challenging using conventional MR imaging. Our aim was to test the hypothesis that conventional and functional MR imaging can accurately diagnose malignancy in patients with indeterminate peripheral nerve sheath tumors. MATERIALS AND METHODS This institutional review board–approved, Health Insurance Portability and Accountability Act–compliant study retrospectively reviewed 61 consecutive patients with 80 indeterminate peripheral nerve sheath tumors. Of these, 31 histologically proved peripheral nerve sheath tumors imaged with conventional (unenhanced T1, fluid-sensitive, contrast-enhanced T1-weighted sequences) and functional MR imaging (DWI/apparent diffusion coefficient mapping, dynamic contrast-enhanced MR imaging) were included. Two observers independently assessed anatomic (size, morphology, signal) and functional (ADC values, early arterial enhancement by dynamic contrast-enhanced MR) features to determine interobserver agreement. The accuracy of MR imaging for differentiating malignant from benign was also determined by receiver operating characteristic analysis. RESULTS Of 31 peripheral nerve sheath tumors, there were 9 malignant (9%) and 22 benign ones (81%). With anatomic sequences, average tumor diameter (6.3 ± 1.8 versus 3.9 ± 2.3 mm, P = .009), ill-defined/infiltrative margins (77% versus 32%; P = .04), and the presence of peritumoral edema (66% versus 23%, P = .01) were different for malignant peripheral nerve sheath tumors and benign peripheral nerve sheath tumors. With functional sequences, minimum ADC (0.47 ± 0.32 × 10?3 mm2/s versus 1.08 ± 0.26 × 10?3 mm2/s; P [H11021] .0001) and the presence of early arterial enhancement (50% versus 11%; P = .03) were different for malignant peripheral nerve sheath tumors and benign peripheral nerve sheath tumors. The minimum ADC (area under receiver operating characteristic curve was 0.89; 95% confidence interval, 0.73– 0.97) and the average tumor diameter (area under the curve = 0.8; 95% CI, 0.66 – 0.94) were accurate in differentiating malignant peripheral nerve sheath tumors from benign peripheral nerve sheath tumors. With threshold values for minimum ADC ? 1.0 × 10?3 mm2/s and an average diameter of ?4.2 cm, malignancy could be diagnosed with 100% sensitivity (95% CI, 66.4%–100%). CONCLUSIONS Average tumor diameter and minimum ADC values are potentially important parameters that may be used to distinguish malignant peripheral nerve sheath tumors from benign peripheral nerve sheath tumors. PMID:24763412

Demehri, S.; Belzberg, A.; Blakeley, J.; Fayad, L.M.

2015-01-01

259

Quantitative assessment of the motor-sensory specificity of the motor and primary sensory neurons after the end-to-side neurorrhaphy.  

PubMed

We sought to evaluate the motor-sensory specificity of the motor and primary sensory neurons after the end-to-side neurorrhaphy. We divided 90 rats into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve as donor nerve and the musculocutaneous nerve as recipient nerve; (2) normal control; and (3) transected nerve with the stumps buried. At 5 months, we monitored the grooming test, the electromyographic recordings, the histologic changes in the nerve, and quantitatively evaluated motoneurons and dorsal root ganglion (DRG) neurons following their retrograde labeling by Fluoro-Gold (Sigma, St. Louis, MO) applied to the musculocutaneous nerve and its biceps brachii branch. Grooming and electrophysiological investigations recovered successfully in the end-to-side group. The implanted musculocutaneous nerve contained varying but satisfactory numbers of axons. In the end-to-side group, the proportion of motoneurons for the biceps brachii branch of musculocutaneous nerve was very similar to the musculocutaneous nerve sections proximal to this branch (17.3% ± 2.7% and 21.7% ± 3.7%, respectively), but it did not correspond with the proportion of the biceps brachii branch of musculocutaneous nerve in the normal group (28.3% ± 3.5%). The present study confirms that limited but functional reinnervation can occur after the end-to-side neurorrhaphy, and the motor-sensory specificity is not important. PMID:23757157

Yu, Qing; Chen, Chengwang; Zhang, Xiaolei; Lv, Lei; Lin, Kang; Chi, Yonglong; Gao, Weiyang

2013-11-01

260

Sensory changes in the territory of the lingual and inferior alveolar nerves following lower third molar extraction  

Microsoft Academic Search

Post-injury inflammation activates nociceptive systems and recruits normally non-nociceptive afferents into a pain processing role. During inflammation, A? low threshold mechanoreceptor afferents that usually mediate tactile sensation acquire properties of nociceptors, allowing them to participate in post-injury spontaneous pain and evoked abnormalities such as tenderness and pain to light touch. This study assessed the sensory consequences of post-injury inflammation following

Eli Eliav; Richard H Gracely

1998-01-01

261

Modelled temperature-dependent excitability behaviour of a single ranvier node for a human peripheral sensory nerve fibre  

Microsoft Academic Search

The objective of this study was to determine whether the Hodgkin–Huxley model for unmyelinated nerve fibres could be modified\\u000a to predict excitability behaviour at Ranvier nodes. Only the model parameters were modified to those of human, with the equations\\u000a left unaltered. A model of a single Ranvier node has been developed as part of a larger model to describe excitation

Jacoba E. Smit; Tania Hanekom; Johan J. Hanekom

2009-01-01

262

Extensive Sprouting of Sensory Afferents and Hyperalgesia Induced by Conditional Expression of Nerve Growth Factor in the Adult Spinal Cord  

Microsoft Academic Search

Genetic transfer of growth-promoting molecules was proposed as a potential strategy to modify the nonpermissive nature of the adult CNS to induce axonal regeneration. To evaluate whether overexpression of neurotrophins or cellular adhesion molecules would effect axonal plasticity, adenoviruses encod- ing fibroblast growth factor-2 (FGF-2\\/Adts), nerve growth factor (NGF\\/Adts), neurotrophin-3, and the cell adhesion molecules N-cadherin and L1 were injected

Mario I. Romero; Nagarathnamma Rangappa; Li Li; Ellis Lightfoot; Mary G. Garry; George M. Smith

2000-01-01

263

Peripheral Nerve Reconstruction after Injury: A Review of Clinical and Experimental Therapies  

PubMed Central

Unlike other tissues in the body, peripheral nerve regeneration is slow and usually incomplete. Less than half of patients who undergo nerve repair after injury regain good to excellent motor or sensory function and current surgical techniques are similar to those described by Sunderland more than 60 years ago. Our increasing knowledge about nerve physiology and regeneration far outweighs our surgical abilities to reconstruct damaged nerves and successfully regenerate motor and sensory function. It is technically possible to reconstruct nerves at the fascicular level but not at the level of individual axons. Recent surgical options including nerve transfers demonstrate promise in improving outcomes for proximal nerve injuries and experimental molecular and bioengineering strategies are being developed to overcome biological roadblocks limiting patient recovery. PMID:25276813

Grinsell, D.; Keating, C. P.

2014-01-01

264

Delayed functional expression of neuronal chemokine receptors following focal nerve demyelination in the rat: a mechanism for the development of chronic sensitization of peripheral nociceptors  

PubMed Central

Background Animal and clinical studies have revealed that focal peripheral nerve axon demyelination is accompanied by nociceptive pain behavior. C-C and C-X-C chemokines and their receptors have been strongly implicated in demyelinating polyneuropathies and persistent pain syndromes. Herein, we studied the degree to which chronic nociceptive pain behavior is correlated with the neuronal expression of chemokines and their receptors following unilateral lysophosphatidylcholine (LPC)-induced focal demyelination of the sciatic nerve in rats. Results Focal nerve demyelination increased behavioral reflex responsiveness to mechanical stimuli between postoperative day (POD) 3 and POD28 in both the hindpaw ipsilateral and contralateral to the nerve injury. This behavior was accompanied by a bilateral increase in the numbers of primary sensory neurons expressing the chemokine receptors CCR2, CCR5, and CXCR4 by POD14, with no change in the pattern of CXCR3 expression. Significant increases in the numbers of neurons expressing the chemokines monocyte chemoattractant protein-1 (MCP-1/CCL2), Regulated on Activation, Normal T Expressed and Secreted (RANTES/CCL5) and interferon ?-inducing protein-10 (IP-10/CXCL10) were also evident following nerve injury, although neuronal expression pattern of stromal cell derived factor-1? (SDF1/CXCL12) did not change. Functional studies demonstrated that acutely dissociated sensory neurons derived from LPC-injured animals responded with increased [Ca2+]i following exposure to MCP-1, IP-10, SDF1 and RANTES on POD 14 and 28, but these responses were largely absent by POD35. On days 14 and 28, rats received either saline or a CCR2 receptor antagonist isomer (CCR2 RA-[R]) or its inactive enantiomer (CCR2 RA-[S]) by intraperitoneal (i.p.) injection. CCR2 RA-[R] treatment of nerve-injured rats produced stereospecific bilateral reversal of tactile hyperalgesia. Conclusion These results suggest that the presence of chemokine signaling by both injured and adjacent, uninjured sensory neurons is correlated with the maintenance phase of a persistent pain state, suggesting that chemokine receptor antagonists may be an important therapeutic intervention for chronic pain. PMID:18076762

Bhangoo, Sonia; Ren, Dongjun; Miller, Richard J; Henry, Kenneth J; Lineswala, Jayana; Hamdouchi, Chafiq; Li, Baolin; Monahan, Patrick E; Chan, David M; Ripsch, Matthew S; White, Fletcher A

2007-01-01

265

Intrinsic and therapeutic factors determining the recovery of motor function after peripheral nerve transection.  

PubMed

Insufficient recovery after peripheral nerve injury has been attributed to (i) poor pathfinding of regrowing axons, (ii) excessive collateral axonal branching at the lesion site and (iii) polyneuronal innervation of the neuromuscular junctions (NMJ). The facial nerve transection model has been used initially to measure restoration of function after varying therapies and to examine the mechanisms underlying their effects. Since it is very difficult to control the navigation of several thousand axons, efforts concentrated on collateral branching and NMJ-polyinnervation. Treatment with antibodies against trophic factors to combat branching improved the precision of reinnervation, but had no positive effects on functional recovery. This suggested that polyneuronal reinnervation--rather than collateral branching--may be the critical limiting factor. The former could be reduced by pharmacological agents known to perturb microtubule assembly and was followed by recovery of function. Because muscle polyinnervation is activity-dependent and can be manipulated, attempts to design a clinically feasible therapy were performed by electrical stimulation or by soft tissue massage. Electrical stimulation applied to the transected facial nerve or to paralysed facial muscles did not improve vibrissal motor performance and failed to diminish polyinnervation. In contrast, gentle stroking of the paralysed muscles (vibrissal, orbicularis oculi, tongue musculature) resulted in full recovery of function. This manual stimulation was also effective after hypoglossal-facial nerve suture and after interpositional nerve grafting, but not after surgical reconstruction of the median nerve. All these findings raise hopes that clinically feasible and effective therapies could be soon designed and tested. PMID:21458252

Skouras, Emmanouil; Ozsoy, Umut; Sarikcioglu, Levent; Angelov, Doychin N

2011-07-01

266

Beyond traditional approaches to understanding the functional role of neuromodulators in sensory cortices  

PubMed Central

Over the last two decades, a vast literature has described the influence of neuromodulatory systems on the responses of sensory cortex neurons (review in Gu, 2002; Edeline, 2003; Weinberger, 2003; Metherate, 2004, 2011). At the single cell level, facilitation of evoked responses, increases in signal-to-noise ratio, and improved functional properties of sensory cortex neurons have been reported in the visual, auditory, and somatosensory modality. At the map level, massive cortical reorganizations have been described when repeated activation of a neuromodulatory system are associated with a particular sensory stimulus. In reviewing our knowledge concerning the way the noradrenergic and cholinergic system control sensory cortices, I will point out that the differences between the protocols used to reveal these effects most likely reflect different assumptions concerning the role of the neuromodulators. More importantly, a gap still exists between the descriptions of neuromodulatory effects and the concepts that are currently applied to decipher the neural code operating in sensory cortices. Key examples that bring this gap into focus are the concept of cell assemblies and the role played by the spike timing precision (i.e., by the temporal organization of spike trains at the millisecond time-scale) which are now recognized as essential in sensory physiology but are rarely considered in experiments describing the role of neuromodulators in sensory cortices. Thus, I will suggest that several lines of research, particularly in the field of computational neurosciences, should help us to go beyond traditional approaches and, ultimately, to understand how neuromodulators impact on the cortical mechanisms underlying our perceptual abilities. PMID:22866031

Edeline, Jean-Marc

2012-01-01

267

Functional and structural analysis of partial optic nerve avulsion due to blunt trauma: Case report  

PubMed Central

Partial optic nerve avulsion (ONA) secondary to finger gouging is an uncommon but devastating injury. A 21-year-old man who had an acute vision loss after accidentally getting poked by himself in his right eye when he fell down during jogging is reported. The patient was diagnosed with partial ONA. Magnetic resonance imaging revealed intact optic nerve. Optical coherence tomography (OCT) revealed deep cavity at the inferior-temporal half of the optic disc. Retinal nerve fiber layer thickness was also thin at the inferior quadrant with circumpapillary OCT scan. Visual field test and electrophysiological tests showed functional abnormality compatible with optic nerve lesion. Diagnostic tools for anatomical and functional evaluation may reveal the course of this injury. PMID:20952839

Mumcuoglu, Tarkan; Durukan, Hakan A; Erdurman, Cuneyt; Hurmeric, Volkan; Gundogan, Fatih C

2010-01-01

268

Functional Specialization of Sensory Cilia by an RFX Transcription Factor Isoform  

PubMed Central

In animals, RFX transcription factors govern ciliogenesis by binding to an X-box motif in the promoters of ciliogenic genes. In Caenorhabditis elegans, the sole RFX transcription factor (TF) daf-19 null mutant lacks all sensory cilia, fails to express many ciliogenic genes, and is defective in many sensory behaviors, including male mating. The daf-19c isoform is expressed in all ciliated sensory neurons and is necessary and sufficient for activating X-box containing ciliogenesis genes. Here, we describe the daf-19(n4132) mutant that is defective in expression of the sensory polycystic kidney disease (PKD) gene battery and male mating behavior, without affecting expression of ciliogenic genes or ciliogenesis. daf-19(n4132) disrupts expression of a new isoform, daf-19m (for function in male mating). daf-19m is expressed in male-specific PKD and core IL2 neurons via internal promoters and remote enhancer elements located in introns of the daf-19 genomic locus. daf-19m genetically programs the sensory functions of a subset of ciliated neurons, independent of daf-19c. In the male-specific HOB neuron, DAF-19M acts downstream of the zinc finger TF EGL-46, indicating that a TF cascade controls the PKD gene battery in this cell-type specific context. We conclude that the RFX TF DAF-19 regulates ciliogenesis via X-box containing ciliogenic genes and controls ciliary specialization by regulating non-X-box containing sensory genes. This study reveals a more extensive role for RFX TFs in generating fully functional cilia. PMID:20923979

Wang, Juan; Schwartz, Hillel T.; Barr, Maureen M.

2010-01-01

269

Using multiple high-count electrode arrays in human median and ulnar nerves to restore sensorimotor function after previous transradial amputation of the hand.  

PubMed

Peripheral nerve interfaces that can record from and stimulate large numbers of different nerve fibers selectively and independently may help restore intuitive and effective motor and sensory function after hand amputation. To this end, and extending previous work in two subjects, two 100-electrode Utah Slanted Electrode Arrays (USEAs) were implanted for four weeks in the residual ulnar and median nerves of a 50-year-old male whose left, dominant hand had been amputated 21 years previously. Subsequent experiments involved 1) recording from USEAs for real-time control of a virtual prosthetic hand; 2) stimulation to evoke somatosensory percepts; and 3) closed-loop sensorimotor control. Overall, partial motor control and sensation were achieved using USEAs. 1) Isolated action potentials recorded from nerve motor fibers, although sparse at these distal implant sites, were activated during fictive movements of the phantom hand. Unlike in our previous two subjects, electromyographic (EMG) activity contributed to most online recordings and decodes, but was reduced in offline analyses using common average referencing. Online and offline Kalman-filter decodes of thresholded neural or EMG spikes independently controlled different digits of the virtual hand with one or two degrees of freedom. 2) Microstimulation through individual electrodes of the two USEAs evoked up to 106 different percepts, covering much of the phantom hand. The subject discriminated among five perceived stimulus locations, and between two somatosensory submodalities at a single location. 3) USEA-evoked percepts, mimicking contact with either a near or distal virtual target, were used to terminate movements of the virtual hand controlled with USEA recordings comprised wholly or mostly of EMG. These results further indicate that USEAs can help restore sensory and motor function after hand loss. PMID:25570369

Clark, Gregory A; Wendelken, Suzanne; Page, David M; Davis, Tyler; Wark, Heather A C; Normann, Richard A; Warren, David J; Hutchinson, Douglas T

2014-08-01

270

Early Auditory Sensory Processing Deficits in Mouse Mutants with Reduced NMDA Receptor Function  

Microsoft Academic Search

Cognitive deficits in schizophrenia include impairments at automatic, preattentive stages of sensory information processing. These deficits are evident in the prepulse inhibition- (PPI) and habituation of the auditory startle response paradigm, the paired tone paradigm in the EEG, and the peak recovery function of auditory evoked potentials (AEP). Administration of NMDA receptor antagonists reliably disrupts PPI and habituation of the

Stephan Bickel; Hans-Peter Lipp; Daniel Umbricht

2008-01-01

271

EFFECTS OF 2,4-DITHIOBIURET ON SENSORY AND MOTOR FUNCTION  

EPA Science Inventory

2,4-Dithiobiuret exposure causes a delayed onset muscle weakness in rats that has been attributed to depressed neuromuscular transmission. he present study compares the effects of DTB on sensory and motor function in rats. dult male Long-Evans hooded rats were exposed to saline, ...

272

Use of ultrasound and fluoroscopy guidance in percutaneous radiofrequency lesioning of the sensory branches of the femoral and obturator nerves.  

PubMed

Hip pain is a common condition that is often seen in patients with multiple comorbidities. Often surgery is not an option due to these comorbidities. Percutaneous radiofrequency lesioning of the articular branches of the obturator and femoral nerves is an alternative treatment for hip pain. Traditionally, fluoroscopy is used to guide needle placement. We report a case where a novel approach was used with ultrasound guidance to visualize vascular and soft tissue structures in real time. The use of ultrasound might help to guide the needle to avoid vascular complications due to anatomical variation between patients. PMID:23656575

Chaiban, Gassan; Paradis, Tyler; Atallah, Joseph

2014-04-01

273

A novel approach for evaluating nerve function in healthy elderly persons: A pilot study  

PubMed Central

Background Motor nerve function decreases with age and can cause abnormalities in motor function. Using newly designed methods, we used evoked electromyograms to evaluate change in motor nerve function. Material/Methods Motor function was assessed by grip strength, timed up-and-go test, 5-m normal walk, and 5-m fastest walk. In addition, motor nerve conduction velocity was calculated by measuring latency differences (NCV) in elderly and young subjects. We also investigated motor nerve conduction velocity by correlation coefficient (NCVCC) and the difference between NCV and NCVCC (DNCV). Results Significant differences were observed in the motor function of elderly and young persons in grip strength, the timed up-and-go test, and the 5-m fastest walk; however, no difference was observed in the 5-m normal walk test. NCVCC was lower than NCV in both elderly and young. The correlation coefficient peak of the NCVCC calculation was lower in elderly than in young. A negative correlation was observed between correlation coefficient peak and DNCV in elderly subjects. Conclusions NCVCC compares the overall shape of compound muscle action potential and reflects not only the fastest motor unit, but also the motor nerve conduction velocity of other motor unit components. A significant negative correlation between DNCV and the correlation coefficient peak was observed only in elderly subjects, suggesting that older individuals, including those that maintain a high level of physical strength, experience a loss of motor nerve function. Thus, changes in motor nerve function among elderly persons can potentially be further examined for clinical use. PMID:23624713

Nishihara, Ken; Kawai, Hisashi; Kanemura, Naohiko; Hara, Motohiko; Naruse, Hideo; Gomi, Toshiaki

2013-01-01

274

Asymptomatic small fiber neuropathy in diabetes mellitus: investigations with intraepidermal nerve fiber density, quantitative sensory testing and laser-evoked potentials  

Microsoft Academic Search

This study aimed at evaluating the performance of a battery of morphological and functional tests for the assessment of small\\u000a nerve fiber loss in asymptomatic diabetic neuropathy (DNP). Patients diagnosed for ?10 years with type 1 (n = 10) or type 2 (n = 13) diabetes mellitus (DM) without conventional symptoms or signs of DNP were recruited and compared with healthy controls\\u000a (n = 18) and patients

Michael Ragé; Nathalie Van Acker; Michiel W. M. Knaapen; Maarten Timmers; Johannes Streffer; Michel P. Hermans; Christian Sindic; Theo Meert; Léon Plaghki

275

Recovery of laryngeal function after intraoperative injury to the recurrent laryngeal nerve  

PubMed Central

Loss of function in the recurrent laryngeal nerve (RLN) during thyroid/parathyroid surgery, despite a macroscopically intact nerve, is a challenge which highlights the sensitivity and complexity of laryngeal innervation. Furthermore, the uncertain prognosis stresses a lack of capability to diagnose the reason behind the impaired function. There is a great deal of literature considering risk factors, surgical technique and mechanisms outside the nerve affecting the incidence of RLN paresis during surgery. To be able to prognosticate recovery in cases of laryngeal dysfunction and voice changes after thyroid surgery, the surgeon would first need to define the presence, location, and type of laryngeal nerve injury. There is little data describing the events within the nerve and the neurobiological reasons for the impaired function related to potential recovery and prognosis. In addition, very little data has been presented in order to clarify any differences between the transient and permanent injury of the RLN. This review aims, from an anatomical and neurobiological perspective, to provide an update on the current understandings of surgically-induced injury to the laryngeal nerves. PMID:25713777

Hydman, Jonas; Svensson, Mikael

2015-01-01

276

Recovery of laryngeal function after intraoperative injury to the recurrent laryngeal nerve.  

PubMed

Loss of function in the recurrent laryngeal nerve (RLN) during thyroid/parathyroid surgery, despite a macroscopically intact nerve, is a challenge which highlights the sensitivity and complexity of laryngeal innervation. Furthermore, the uncertain prognosis stresses a lack of capability to diagnose the reason behind the impaired function. There is a great deal of literature considering risk factors, surgical technique and mechanisms outside the nerve affecting the incidence of RLN paresis during surgery. To be able to prognosticate recovery in cases of laryngeal dysfunction and voice changes after thyroid surgery, the surgeon would first need to define the presence, location, and type of laryngeal nerve injury. There is little data describing the events within the nerve and the neurobiological reasons for the impaired function related to potential recovery and prognosis. In addition, very little data has been presented in order to clarify any differences between the transient and permanent injury of the RLN. This review aims, from an anatomical and neurobiological perspective, to provide an update on the current understandings of surgically-induced injury to the laryngeal nerves. PMID:25713777

Mattsson, Per; Hydman, Jonas; Svensson, Mikael

2015-02-01

277

Functional role of peripheral opioid receptors in the regulation of cardiac spinal afferent nerve activity during myocardial ischemia  

PubMed Central

Thinly myelinated A?-fiber and unmyelinated C-fiber cardiac sympathetic (spinal) sensory nerve fibers are activated during myocardial ischemia to transmit the sensation of angina pectoris. Although recent observations showed that myocardial ischemia increases the concentrations of opioid peptides and that the stimulation of peripheral opioid receptors inhibits chemically induced visceral and somatic nociception, the role of opioids in cardiac spinal afferent signaling during myocardial ischemia has not been studied. The present study tested the hypothesis that peripheral opioid receptors modulate cardiac spinal afferent nerve activity during myocardial ischemia by suppressing the responses of cardiac afferent nerve to ischemic mediators like bradykinin and extracellular ATP. The nerve activity of single unit cardiac afferents was recorded from the left sympathetic chain (T2–T5) in anesthetized cats. Forty-three ischemically sensitive afferent nerves (conduction velocity: 0.32–3.90 m/s) with receptive fields in the left and right ventricles were identified. The responses of these afferent nerves to repeat ischemia or ischemic mediators were further studied in the following protocols. First, epicardial administration of naloxone (8 ?mol), a nonselective opioid receptor antagonist, enhanced the responses of eight cardiac afferent nerves to recurrent myocardial ischemia by 62%, whereas epicardial application of vehicle (PBS) did not alter the responses of seven other cardiac afferent nerves to ischemia. Second, naloxone applied to the epicardial surface facilitated the responses of seven cardiac afferent nerves to epicardial ATP by 76%. Third, administration of naloxone enhanced the responses of seven other afferent nerves to bradykinin by 85%. In contrast, in the absence of naloxone, cardiac afferent nerves consistently responded to repeated application of ATP (n = 7) or bradykinin (n = 7). These data suggest that peripheral opioid peptides suppress the responses of cardiac sympathetic afferent nerves to myocardial ischemia and ischemic mediators like ATP and bradykinin. PMID:23645463

Longhurst, John C.

2013-01-01

278

EFFICACY OF A NOVEL DEVICE FOR ASSESSMENT OF AUTONOMIC SENSORY FUNCTION IN THE RAT BLADDER  

PubMed Central

Purpose We developed and tested the efficacy of an implantable bladder device which, when combined with the Neurometer®, can be used to assess fiber-specific afferent sensation of the bladder in the rat. Materials and Methods We developed an implantable bladder device which applies selective nerve fiber stimuli (250 Hz for small myelinated (A?), and 5 Hz for unmyelinated (C) fibers) to the bladder mucosa in the rat in order to obtain the bladder sensory perception threshold (SPT) values. We performed three experiments on fifty-five female Sprague-Dawley rats, examining the effects of our device on voiding habits; assessing the inter-observer reliability of SPT; and the effects of intravesical administration of resiniferatoxin and lidocaine on the SPT. Results The SPT values obtained by two blinded, independent observers were not different from one another (p= 0.41). The SPT values obtained at both stimulation frequencies remained constant for at least 3 weeks after device implantation. A significant increase in SPT values after instillation of resiniferatoxin (p = 0.02) was noted at a stimulus frequency of 5 Hz, whereas intravesical lidocaine led to an immediate increase in SPT at both 250 and 5 Hz. Device implantation led to an early decreased voided volume and increased frequency of voids, however these parameters returned to normal after 4 days. Conclusions Assessment of bladder afferent sensation with our newly developed device is feasible in rats, and provides sensory perception thresholds that appear to be fiber-type selective for autonomic bladder afferent nerves. PMID:18206176

Abouassaly, Robert; Liu, Guiming; Yamada, Yasuhiro; Ukimura, Osamu; Daneshgari, Firouz

2014-01-01

279

Nerve and Nerve Root Biomechanics  

Microsoft Academic Search

\\u000a Together, the relationship between the mechanical response of neural tissues and the related mechanisms of injury provide\\u000a a foundation for defining relevant thresholds for injury. The nerves and nerve roots are biologic structures with specific\\u000a and important functions, and whose response to mechanical loading can have immediate, long-lasting and widespread consequences.\\u000a In particular, when nerves or nerve roots are mechanically

Kristen J. Nicholson; Beth A. Winkelstein

280

Grapefruit-seed extract attenuates ethanol-and stress-induced gastric lesions via activation of prostaglandin, nitric oxide and sensory nerve pathways  

PubMed Central

AIM: Grapefruit-seed extract (GSE) containing flavonoids, possesses antibacterial and antioxidative properties but whether it influences the gastric defense mechanism and gastroprotection against ethanol- and stress-induced gastric lesions remains unknown. METHODS: We compared the effects of GSE on gastric mucosal lesions induced in rats by topical application of 100% ethanol or 3.5 h of water immersion and restraint stress (WRS) with or without (A) inhibition of cyclooxygenase (COX)-1 activity by indomethacin and rofecoxib, the selective COX-2 inhibitor, (B) suppression of NO-synthase with L-NNA (20 mg/kg ip), and (C) inactivation by capsaicin (125 mg/kg sc) of sensory nerves with or without intragastric (ig) pretreatment with GSE applied 30 min prior to ethanol or WRS. One hour after ethanol and 3.5 h after the end of WRS, the number and area of gastric lesions were measured by planimetry, the gastric blood flow (GBF) was assessed by H2-gas clearance technique and plasma gastrin levels and the gastric mucosal generation of PGE2, superoxide dismutase (SOD) activity and malonyldialdehyde (MDA) concentration, as an index of lipid peroxidation were determined. RESULTS: Ethanol and WRS caused gastric lesions accompanied by the significant fall in the GBF and SOD activity and the rise in the mucosal MDA content. Pretreatment with GSE (8-64 mg/kg i g) dose-dependently attenuated gastric lesions induced by 100% ethanol and WRS; the dose reducing these lesions by 50% (ID50) was 25 and 36 mg/kg, respectively, and this protective effect was similar to that obtained with methyl PGE2 analog (5 ?g/kg i g). GSE significantly raised the GBF, mucosal generation of PGE2, SOD activity and plasma gastrin levels while attenuating MDA content. Inhibition of PGE2 generation with indomethacin or rofecoxib and suppression of NO synthase by L-NNA or capsaicin denervation reversed the GSE-induced protection and the accompanying hyperemia. Co-treatment of exogenous calcitonine gene-related peptide (CGRP) with GSE restored the protection and accompanying hyperemic effects of GSE in rats with capsaicin denervation. CONCLUSION: GSE exerts a potent gastroprotective activity against ethanol and WRS-induced gastric lesions via an increase in endogenous PG generation, suppression of lipid peroxidation and hyperemia possibly mediated by NO and CGRP released from sensory nerves. PMID:16425415

Brzozowski, Tomasz; Konturek, Peter C; Drozdowicz, Danuta; Konturek, Stanislaw J; Zayachivska, Oxana; Pajdo, Robert; Kwiecien, Slawomir; Pawlik, Wieslaw W; Hahn, Eckhart G

2005-01-01

281

Failure of action potential propagation in sensory neurons: mechanisms and loss of afferent filtering in C-type units after painful nerve injury  

PubMed Central

The T-junction of sensory neurons in the dorsal root ganglion (DRG) is a potential impediment to action potential (AP) propagation towards the CNS. Using intracellular recordings from rat DRG neuronal somata during stimulation of the dorsal root, we determined that the maximal rate at which all of 20 APs in a train could successfully transit the T-junction (following frequency) was lowest in C-type units, followed by A-type units with inflected descending limbs of the AP, and highest in A-type units without inflections. In C-type units, following frequency was slower than the rate at which AP trains could be produced in either dorsal root axonal segments or in the soma alone, indicating that the T-junction is a site that acts as a low-pass filter for AP propagation. Following frequency was slower for a train of 20 APs than for two, indicating that a cumulative process leads to propagation failure. Propagation failure was accompanied by diminished somatic membrane input resistance, and was enhanced when Ca2+-sensitive K+ currents were augmented or when Ca2+-sensitive Cl? currents were blocked. After peripheral nerve injury, following frequencies were increased in axotomized C-type neurons and decreased in axotomized non-inflected A-type neurons. These findings reveal that the T-junction in sensory neurons is a regulator of afferent impulse traffic. Diminished filtering of AP trains at the T-junction of C-type neurons with axotomized peripheral processes could enhance the transmission of activity that is ectopically triggered in a neuroma or the neuronal soma, possibly contributing to pain generation. PMID:23148321

Gemes, Geza; Koopmeiners, Andrew; Rigaud, Marcel; Lirk, Philipp; Sapunar, Damir; Bangaru, Madhavi Latha; Vilceanu, Daniel; Garrison, Sheldon R; Ljubkovic, Marko; Mueller, Samantha J; Stucky, Cheryl L; Hogan, Quinn H

2013-01-01

282

Misdirection of regenerating axons and functional recovery following sciatic nerve injury in rats.  

PubMed

Poor functional recovery found after peripheral nerve injury has been attributed to the misdirection of regenerating axons to reinnervate functionally inappropriate muscles. We applied brief electrical stimulation (ES) to the common fibular (CF) but not the tibial (Tib) nerve just prior to transection and repair of the entire rat sciatic nerve, to attempt to influence the misdirection of its regenerating axons. The specificity with which regenerating axons reinnervated appropriate targets was evaluated physiologically using compound muscle action potentials (M responses) evoked from stimulation of the two nerve branches above the injury site. Functional recovery was assayed using the timing of electromyography (EMG) activity recorded from the tibialis anterior (TA) and soleus (Sol) muscles during treadmill locomotion and kinematic analysis of hindlimb locomotor movements. Selective ES of the CF nerve resulted in restored M-responses at earlier times than in unstimulated controls in both TA and Sol muscles. Stimulated CF axons reinnervated inappropriate targets to a greater extent than unstimulated Tib axons. During locomotion, functional antagonist muscles, TA and Sol, were coactivated both in stimulated rats and in unstimulated but injured rats. Hindlimb kinematics in stimulated rats were comparable to untreated rats, but significantly different from intact controls. Selective ES promotes enhanced axon regeneration but does so with decreased fidelity of muscle reinnervation. Functional recovery is neither improved nor degraded, suggesting that compensatory changes in the outputs of the spinal circuits driving locomotion may occur irrespective of the extent of misdirection of regenerating axons in the periphery. PMID:21120925

Hamilton, Shirley K; Hinkle, Marcus L; Nicolini, Jennifer; Rambo, Lindsay N; Rexwinkle, April M; Rose, Sam J; Sabatier, Manning J; Backus, Deborah; English, Arthur W

2011-01-01

283

A Requirement for Commissureless2 Function during Dipteran Insect Nerve Cord Development  

PubMed Central

Background In Drosophila melanogaster, commissureless (comm) function is required for proper nerve cord development. Although comm orthologs have not been identified outside of Drosophila species, some insects possess orthologs of Drosophila comm2, which may also regulate embryonic nerve cord development. Here, this hypothesis is explored through characterization of comm2 genes in two disease vector mosquitoes. Results Culex quinquefasciatus (West Nile and lymphatic filiariasis vector) has three comm2 genes that are expressed in the developing nerve cord. Aedes aegypti (dengue and yellow fever vector) has a single comm2 gene that is expressed in commissural neurons projecting axons toward the midline. Loss of comm2 function in both A. aegypti and D. melanogaster was found to result in loss of commissure defects that phenocopy the frazzled (fra) loss of function phenotypes observed in both species. Loss of fra function in either insect was found to result in decreased comm2 transcript levels during nerve cord development. Conclusions The results of this investigation suggest that Fra downregulates repulsion in precrossing commissural axons by regulating comm2 levels in both A. aegypti and D. melanogaster, both of which require Comm2 function for proper nerve cord development, PMID:24026811

Sarro, Joseph; Andrews, Emily; Sun, Longhua; Behura, Susanta K.; Tan, John C.; Zeng, Erliang; Severson, David W.; Duman-Scheel, Molly

2013-01-01

284

The effect of memantine on functional recovery of the facial nerve after crush injury.  

PubMed

The objective of this study is to establish whether memantine is an alternative and effective treatment on facial nerve recovery after crush injury, and also to analyze the effective doses of this promising agent. This is a randomized controlled animal study. 40 rats underwent crush injury to left main trunk of the facial nerve, and divided into 4 groups; (1) control (saline treated), (2) 5-mg/kg memantine, (3) 10-mg/kg memantine, and (4) 20-mg/kg memantine group. Facial nerve functions were evaluated by eye reflex, and whisker movement compared to the unaffected side. They were scored on a 3-point scale. On day 28, the rats were sacrificed, and the facial nerves were dissected. The paraffin sections were studied with caspase-3 immunostaining. According to statistical data, the recovery in Group 4 began significantly earlier than the other groups on the basis of restoring eye blink reflexes and whisker movement. Groups 2 and 3 showed faster recovery than Group 1 on the basis of whisker movement. The caspase-3 positive staining was rarely detected in all groups. The Kruskal–Wallis test revealed that Group 4 showed fewer apoptotic cells than other groups; this was statistically significant. However, the Mann–Whitney U test with the Bonferroni correction did not reveal any significant difference between the groups. In conclusion, this study revealed that memantine acted to restore facial nerve functions, and accelerate recovery after facial nerve injury by inhibiting apoptosis. PMID:24659363

Topdag, Murat; Topdag, Deniz Ozlem; Ila, Kadri; Muezzinoglu, Bahar; Yaprak, Busra; Ozturk, Murat; Caliskan, Sebla; Iseri, Mete

2015-02-01

285

Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves  

PubMed Central

Junctional adhesion molecule-C (JAM-C) is an adhesion molecule expressed at junctions between adjacent endothelial and epithelial cells and implicated in multiple inflammatory and vascular responses. In addition, we recently reported on the expression of JAM-C in Schwann cells (SCs) and its importance for the integrity and function of peripheral nerves. To investigate the role of JAM-C in neuronal functions further, mice with a specific deletion of JAM-C in SCs (JAM-C SC KO) were generated. Compared to wild-type (WT) controls, JAM-C SC KO mice showed electrophysiological defects, muscular weakness, and hypersensitivity to mechanical stimuli. In addressing the underlying cause of these defects, nerves from JAM-C SC KO mice were found to have morphological defects in the paranodal region, exhibiting increased nodal length as compared to WTs. The study also reports on previously undetected expressions of JAM-C, namely on perineural cells, and in line with nociception defects of the JAM-C SC KO animals, on finely myelinated sensory nerve fibers. Collectively, the generation and characterization of JAM-C SC KO mice has provided unequivocal evidence for the involvement of SC JAM-C in the fine organization of peripheral nerves and in modulating multiple neuronal responses.—Colom, B., Poitelon, Y., Huang, W., Woodfin, A., Averill, S., Del Carro, U., Zambroni, D., Brain, S. D., Perretti, M., Ahluwalia, A., Priestley, J. V., Chavakis, T., Imhof, B. A., Feltri, M. L., Nourshargh, S. Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves. PMID:22090315

Colom, Bartomeu; Poitelon, Yannick; Huang, Wenlong; Woodfin, Abigail; Averill, Sharon; Del Carro, Ubaldo; Zambroni, Desirée; Brain, Susan D.; Perretti, Mauro; Ahluwalia, Amrita; Priestley, John V.; Chavakis, Triantafyllos; Imhof, Beat A.; Feltri, M. Laura; Nourshargh, Sussan

2012-01-01

286

Vanishing senses—restoration of sensory functions by electronic implants  

Microsoft Academic Search

Is the endeavour to restore perceptive brain functions by electronic implants the first step on the way to create bionic cyborgs? Can we augment or multiply our senses by directly contacting computer chips to the brain? Will bio-implants influence and permanently change human psyche? Almost 50 years ago, the foundation of the new field of neuroprosthetics propelled research aimed at

Steffen K. Rosahl

2004-01-01

287

Poor motor function is associated with reduced sensory processing after stroke.  

PubMed

The possibility to regain motor function after stroke depends on the intactness of motor and sensory pathways. In this study, we evaluated afferent sensory pathway information transfer and processing after stroke with the coherence between cortical activity and a position perturbation (position-cortical coherence, PCC). Eleven subacute stroke survivors participated in this study. Subjects performed a motor task with the affected and non-affected arm while continuous wrist position perturbations were applied. Cortical activity was measured using EEG. PCC was calculated between position perturbation and EEG at the contralateral and ipsilateral sensorimotor area. The presence of PCC was quantified as the number of frequencies where PCC is larger than zero across the sensorimotor area. All subjects showed significant contralateral PCC in affected and non-affected wrist tasks. Subjects with poor motor function had a reduced presence of contralateral PCC compared with subjects with good motor function in the affected wrist tasks. Amplitude of significant PCC did not differ between subjects with good and poor motor function. Our results show that poor motor function is associated with reduced sensory pathway information transfer and processing in subacute stroke subjects. Position-cortical coherence may provide additional insight into mechanisms of recovery of motor function after stroke. PMID:25651979

Campfens, S Floor; Zandvliet, Sarah B; Meskers, Carel G M; Schouten, Alfred C; van Putten, Michel J A M; van der Kooij, Herman

2015-04-01

288

Ageing alters perivascular nerve function of mouse mesenteric arteries in vivo.  

PubMed

Abstract? Mesenteric arteries (MAs) are studied widely in vitro but little is known of their reactivity in vivo. Transgenic animals have enabled Ca(2+) signalling to be studied in isolated MAs but the reactivity of these vessels in vivo is undefined. We tested the hypothesis that ageing alters MA reactivity to perivascular nerve stimulation (PNS) and adrenoreceptor (AR) activation during blood flow control. First- (1A), second- (2A) and third-order (3A) MAs of pentobarbital-anaesthetized Young (3-6 months) and Old (24-26 months) male and female Cx40(BAC)-GCaMP2 transgenic mice (C57BL/6 background; positive or negative for the GCaMP2 transgene) were studied with intravital microscopy. A segment of jejunum was exteriorized and an MA network was superfused with physiological salt solution (pH 7.4, 37°C). Resting tone was 10% in MAs of Young and Old mice; diameters were ?5% (1A), 20% (2A) and 40% (3A) smaller (P 0.05) in Old mice. Throughout MA networks, vasoconstriction increased with PNS frequency (1-16 Hz) but was ?20% less in Young vs. Old mice (P 0.05) and was inhibited by tetrodotoxin (1 ?m). Capsaicin (10 ?m; to inhibit sensory nerves) enhanced MA constriction to PNS (P 0.05) by ?20% in Young but not Old mice. Phenylephrine (an ?1AR agonist) potency was greater in Young mice (P 0.05) with similar efficacy (?60% constriction) across ages and MA branches. Constrictions to UK14304 (an ?2AR agonist) were less (?20%; P 0.05) and were unaffected by ageing. Irrespective of sex or transgene expression, ageing consistently reduced the sensitivity of MAs to ?1AR vasoconstriction while blunting the attenuation of sympathetic vasoconstriction by sensory nerves. These findings imply substantive alterations in splanchnic blood flow control with ageing. PMID:23247111

Westcott, Erika B; Segal, Steven S

2013-03-01

289

Increase in NGF content and nerve fiber sprouting in human allergic contact eczema  

Microsoft Academic Search

There is increasing evidence for an intimate interaction of the skin and the nervous system. As known from animal studies, nerve growth factor (NGF) is essential for the innervation density and functional properties of sensory neurons of the skin during embryogenesis and in adulthood, and possibly during cutaneous inflammation. This study examined NGF content and sprouting of nerves during the

Ilka Kinkelin; Sandra Mötzing; Martin Koltzenburg; Eva-Bettina Bröcker

2000-01-01

290

Importance of Tissue Morphology Relative to Patient Reports of Symptoms and Functional Limitations Resulting From Median Nerve Pathology  

PubMed Central

Significant data exist for the personal, environmental, and occupational risk factors for carpal tunnel syndrome. Few data, however, explain the interrelationship of tissue morphology to these factors among patients with clinical presentation of median nerve pathology. Therefore, our primary objective was to examine the relationship of various risk factors that may be predictive of subjective reports of symptoms or functional deficits accounting for median nerve morphology. Using diagnostic ultrasonography, we observed real-time median nerve morphology among 88 participants with varying reports of symptoms or functional limitations resulting from median nerve pathology. Body mass index, educational level, and nerve morphology were the primary predictive factors. Monitoring median nerve morphology with ultrasonography may provide valuable information for clinicians treating patients with symptoms of median nerve pathology. Sonographic measurements may be a useful clinical tool for improving treatment planning and provision, documenting patient status, or measuring clinical outcomes of prevention and rehabilitation interventions. PMID:23245784

Evans, Kevin D.; Li, Xiaobai; Sommerich, Carolyn M.; Case-Smith, Jane

2013-01-01

291

Double peak sensory responses at submaximal stimulation  

Microsoft Academic Search

Objective: The objective of the study was to obtain knowledge about the different physiological situations where a double peak sensory response normally occurs and to better understand the significance of this particular sensory response.Methods: In 14 healthy subjects, conventional orthodromic sensory nerve conduction studies were performed on the median and ulnar nerves using submaximal stimulation. Various stimulus strengths, polarity, electrode

Irene Aprile; Erik Stĺlberg; Pietro Tonali; Luca Padua

2003-01-01

292

Effects of the Nerve Mobilization Technique on Lower Limb Function in Patients with Poststroke Hemiparesis  

PubMed Central

[Purpose] The purpose of the study was to determine the effects of a sciatic nerve mobilization technique on improvement of lower limb function in patient with poststroke hemiparesis. [Subjects] Twenty- two stroke patients participated in this study. [Methods] They were randomly selected based on selection criteria and divided into two groups. In the subject group (n=10), sciatic nerve mobilization with conventional physical therapy was applied to patients. In the control group (n=10), only conventional physical therapy was applied to stroke patients. [Results] There were significant differences between the two groups in pressure, sway, total pressure, angle of the knee joint, and functional reaching test results in the intervention at two weeks and at four weeks. [Conclusion] The present study showed that sciatic nerve mobilization with conventional physical therapy was more effective for lower limb function than conventional physical therapy alone in patient with poststroke hemiparesis. PMID:25140078

Cha, Hyun-Kyu; Cho, Hyuk-Shin; Choi, Jong-Duk

2014-01-01

293

Functional diversity among sensory receptors in a Drosophila olfactory circuit  

PubMed Central

The ability of an animal to detect, discriminate, and respond to odors depends on the function of its olfactory receptor neurons (ORNs), which in turn depends ultimately on odorant receptors. To understand the diverse mechanisms used by an animal in olfactory coding and computation, it is essential to understand the functional diversity of its odor receptors. The larval olfactory system of Drosophila melanogaster contains 21 ORNs and a comparable number of odorant receptors whose properties have been examined in only a limited way. We systematically screened them with a panel of ?500 odorants, yielding >10,000 receptor–odorant combinations. We identify for each of 19 receptors an odorant that excites it strongly. The responses elicited by each of these odorants are analyzed in detail. The odorants elicited little cross-activation of other receptors at the test concentration; thus, low concentrations of many of these odorants in nature may be signaled by a single ORN. The receptors differed dramatically in sensitivity to their cognate odorants. The responses showed diverse temporal dynamics, with some odorants eliciting supersustained responses. An intriguing question in the field concerns the roles of different ORNs and receptors in driving behavior. We found that the cognate odorants elicited behavioral responses that varied across a broad range. Some odorants elicited strong physiological responses but weak behavioral responses or weak physiological responses but strong behavioral responses. PMID:23690583

Mathew, Dennis; Martelli, Carlotta; Kelley-Swift, Elizabeth; Brusalis, Christopher; Gershow, Marc; Samuel, Aravinthan D. T.; Emonet, Thierry; Carlson, John R.

2013-01-01

294

Olfactory stimulatory with grapefruit and lavender oils change autonomic nerve activity and physiological function.  

PubMed

This review summarizes the effects of olfactory stimulation with grapefruit and lavender oils on autonomic nerve activity and physiological function. Olfactory stimulation with the scent of grapefruit oil (GFO) increases the activity of sympathetic nerves that innervate white and brown adipose tissues, the adrenal glands, and the kidneys, decreases the activity of the gastric vagal nerve in rats and mice. This results in an increase in lipolysis, thermogenesis, and blood pressure, and a decrease in food intake. Olfactory stimulation with the scent of lavender oil (LVO) elicits the opposite changes in nerve activity and physiological variables. Olfactory stimulation with scent of limonene, a component of GFO, and linalool, a component of LVO, has similar effects to stimulation with GFO and LVO, respectively. The histamine H1-receptor antagonist, diphenhydramine, abolishes all GFO-induced changes in nerve activity and physiological variables, and the hitstamine H3-receptor antagonist, thioperamide, eliminates all LVO-induced changes. Lesions to the hypothalamic suprachiasmatic nucleus and anosmic treatment with ZnSO4 also abolish all GFO- and LVO-induced changes. These findings indicate that limonene and linalool might be the active substances in GFO and LVO, and suggest that the suprachiasmatic nucleus and histamine are involved in mediating the GFO- and LVO-induced changes in nerve activity and physiological variables. PMID:25002406

Nagai, Katsuya; Niijima, Akira; Horii, Yuko; Shen, Jiao; Tanida, Mamoru

2014-10-01

295

Prevention of paclitaxel-evoked painful peripheral neuropathy by acetyl-L-carnitine: Effects on axonal mitochondria, sensory nerve fiber terminal arbors, and cutaneous Langerhans cells  

PubMed Central

Prophylactic treatment with acetyl-L-carnitine (ALCAR) prevents the neuropathic pain syndrome that is evoked by the chemotherapeutic agent, paclitaxel. The paclitaxel-evoked pain syndrome is associated with degeneration of the intraepidermal terminal arbors of primary afferent neurons, with the activation of cutaneous Langerhans cells, and with an increased incidence of swollen and vacuolated axonal mitochondria in A-fibers and C-fibers. Previous work suggests that ALCAR is neuroprotective in other nerve injury models and that it improves mitochondrial dysfunction. Thus, we examined whether the prophylactic efficacy of ALCAR was associated with the prevention of intraepidermal terminal arbor degeneration, the inhibition of Langerhans cell activation, or the inhibition of swelling and vacuolation of axonal mitochondria. In animals with a confirmed ALCAR effect, we found no evidence of a neuroprotective effect on the paclitaxel-evoked degeneration of sensory terminal arbors or an inhibition of the paclitaxel-evoked activation of Langerhans cells. However, ALCAR treatment completely prevented the paclitaxel-evoked increase in the incidence of swollen and vacuolated C-fiber mitochondria, while having no effect on the paclitaxel-evoked changes in A-fiber mitochondria. Our results suggest that the efficacy of prophylactic ALCAR treatment against the paclitaxel-evoked pain may be related to a protective effect on C-fiber mitochondria. PMID:18078936

Jin, Hai Wei; Flatters, Sarah J.L.; Xiao, Wen Hua; Mulhern, Howard L.; Bennett, Gary J.

2008-01-01

296

Structural and functional association between substance P- and calcitonin gene-related peptide-immunoreactive nerves and accessory cells in the rat dental pulp.  

PubMed

Defense mechanisms of the dentin/pulp complex involve a variety of biological systems in which immunocompetent cells, the nervous system, and the vascular supply play important roles. In the present study, pulpal accessory cells were examined regarding (i) their structural relationship to nerves and (ii) how the functional capacities of these cells were affected by neuropeptides. Micro-anatomic association was investigated in the normal rat molar pulp with the use of double-immunofluorescence staining and dual-channel confocal laser scanning microscopy. Examinations of confocal laser scanning microscopic images from single focal planes revealed the presence of apparent contacts between thin, varicose nerve fibers and immunocompetent cells, indicating proximity between these two structures. The close associations were most frequently observed in the para-odontoblastic region of the coronal pulp, where more than 70% of class II antigen-expressing (OX6+) cells showed proximity to nerve fibers immunoreactive to calcitonin gene-related peptide. The corresponding figure for substance P was about 50%. ED2+ macrophages closely associated with nerves were less frequently observed. Functional studies conducted in vitro demonstrated that 10(-9) to 10(-7) mol/L of substance P significantly increased (p < 0.05), while 10(-7) to 10(-6) mol/L of calcitonin gene-related peptide suppressed (p < 0.01) proliferation of purified T-lymphocytes stimulated with sub-optimal concentrations of concanavalin A in the presence of rat incisor pulpal cells as accessory cells. These data suggest that pulpal sensory nerve fibers and their products may have an influence upon the immune defense of the dental pulp. PMID:9390474

Okiji, T; Jontell, M; Belichenko, P; Dahlgren, U; Bergenholtz, G; Dahlström, A

1997-12-01

297

Immunohistochemical analysis of the adhesive papillae of Botrylloides leachi (Chordata, Tunicata, Ascidiacea): Implications for their sensory function  

Microsoft Academic Search

Most ascidian larvae settle and begin adhesion by means of three mucus secreting and sensory organs, the adhesive papillae or palps. However, the adhesive papillae of Botrylloides genus larvae, despite their name, have only a sensory function. By immunohistochemical localization of serotonin and ??tubulin, we demonstrated that the adhesive papillae of Botrylloides leachi contain two distinct types of neurons with

R. Pennati; G. Zega; S. Groppelli; F. De Bernardi

2007-01-01

298

Free vascularized deep peroneal nerve grafts.  

PubMed

An ideal donor site for vascularized nerve grafts should have a constant anatomy, minimal functional loss after the nerve has been sacrificed, and a dependable blood supply parallel to the nerve over a relatively long distance. Creating a pedicle for a free vascularized deep peroneal nerve graft with the anterior tibial vessels seems to be a most suitable method for repairing long nerve gaps of over 20 cm and digital nerve defects with severe finger damage. Applications of this nerve graft to digital nerve losses with severely scarred beds created by avulsion injury, and two-stage reconstruction in some partial brachial plexus palsies (free vascularized nerve graft in the first stage and free vascularized muscle graft in the second stage) are well indicated. Advantages of this technique are: (1) A long nerve graft (up to 25 cm) can be obtained, and anomalies are rare (the nerve is absent in only 4 percent of cases). (2) The caliber of the vascular pedicle is large (approximately equal to 3 mm). (3) The nerve has a sufficient blood supply from the collateral blood vessels. (4) The graft can be easily obtained in the supine position. (5) A monitoring skin flap, based on the inferior lateral peroneal artery, can be attached to the nerve graft. (6) Sensory loss resulting from the sacrifice of the nerve covers a minimal area. (7) A donor scar on the anterior aspect of the lower leg is more acceptable than one on the posterior aspect because of less movement in walking. Disadvantages of this technique are: (1) Sacrifice of the large vessels in the lower leg may result in circulatory complications in the donor foot; to avoid this problem, preoperative angiography is recommended. (2) The donor scar is in an exposed area in female patients. (3) There may be temporary postoperative edema and disability in the donor leg. PMID:8726331

Koshima, I; Okumoto, K; Umeda, N; Moriguchi, T; Ishii, R; Nakayama, Y

1996-04-01

299

Redox and Nitric Oxide-Mediated Regulation of Sensory Neuron Ion Channel Function  

PubMed Central

Abstract Significance: Reactive oxygen and nitrogen species (ROS and RNS, respectively) can intimately control neuronal excitability and synaptic strength by regulating the function of many ion channels. In peripheral sensory neurons, such regulation contributes towards the control of somatosensory processing; therefore, understanding the mechanisms of such regulation is necessary for the development of new therapeutic strategies and for the treatment of sensory dysfunctions, such as chronic pain. Recent Advances: Tremendous progress in deciphering nitric oxide (NO) and ROS signaling in the nervous system has been made in recent decades. This includes the recognition of these molecules as important second messengers and the elucidation of their metabolic pathways and cellular targets. Mounting evidence suggests that these targets include many ion channels which can be directly or indirectly modulated by ROS and NO. However, the mechanisms specific to sensory neurons are still poorly understood. This review will therefore summarize recent findings that highlight the complex nature of the signaling pathways involved in redox/NO regulation of sensory neuron ion channels and excitability; references to redox mechanisms described in other neuron types will be made where necessary. Critical Issues: The complexity and interplay within the redox, NO, and other gasotransmitter modulation of protein function are still largely unresolved. Issues of specificity and intracellular localization of these signaling cascades will also be addressed. Future Directions: Since our understanding of ROS and RNS signaling in sensory neurons is limited, there is a multitude of future directions; one of the most important issues for further study is the establishment of the exact roles that these signaling pathways play in pain processing and the translation of this understanding into new therapeutics. Antioxid. Redox Signal. 22, 486–504. PMID:24735331

2015-01-01

300

Sensoric Protection after Median Nerve Injury: Babysitter-Procedure Prevents Muscular Atrophy and Improves Neuronal Recovery  

PubMed Central

The babysitter-procedure might offer an alternative when nerve reconstruction is delayed in order to overcome muscular atrophy due to denervation. In this study we aimed to show that a sensomotoric babysitter-procedure after median nerve injury is capable of preserving irreversible muscular atrophy. The median nerve of 20 female Wistar rats was denervated. 10 animals received a sensory protection with the N. cutaneous brachii. After six weeks the median nerve was reconstructed by autologous nerve grafting from the contralateral median nerve in the babysitter and the control groups. Grasping tests measured functional recovery over 15 weeks. At the end of the observation period the weight of the flexor digitorum sublimis muscle was determined. The median nerve was excised for histological examinations. Muscle weight (P < 0.0001) was significantly superior in the babysitter group compared to the control group at the end of the study. The histological evaluation revealed a significantly higher diameter of axons (P = 0.0194), nerve fiber (P = 0.0409), and nerve surface (P = 0.0184) in the babysitter group. We conclude that sensory protection of a motor nerve is capable of preserving muscule weight and we may presume that metabolism of the sensory nerve was sufficient to keep the target muscle's weight and vitality. PMID:25133176

Beck-Broichsitter, Benedicta E.; Becker, Stephan T.; Lamia, Androniki; Fregnan, Federica; Sinis, Nektarios

2014-01-01

301

Sensoric protection after median nerve injury: babysitter-procedure prevents muscular atrophy and improves neuronal recovery.  

PubMed

The babysitter-procedure might offer an alternative when nerve reconstruction is delayed in order to overcome muscular atrophy due to denervation. In this study we aimed to show that a sensomotoric babysitter-procedure after median nerve injury is capable of preserving irreversible muscular atrophy. The median nerve of 20 female Wistar rats was denervated. 10 animals received a sensory protection with the N. cutaneous brachii. After six weeks the median nerve was reconstructed by autologous nerve grafting from the contralateral median nerve in the babysitter and the control groups. Grasping tests measured functional recovery over 15 weeks. At the end of the observation period the weight of the flexor digitorum sublimis muscle was determined. The median nerve was excised for histological examinations. Muscle weight (P < 0.0001) was significantly superior in the babysitter group compared to the control group at the end of the study. The histological evaluation revealed a significantly higher diameter of axons (P = 0.0194), nerve fiber (P = 0.0409), and nerve surface (P = 0.0184) in the babysitter group. We conclude that sensory protection of a motor nerve is capable of preserving muscule weight and we may presume that metabolism of the sensory nerve was sufficient to keep the target muscle's weight and vitality. PMID:25133176

Beck-Broichsitter, Benedicta E; Becker, Stephan T; Lamia, Androniki; Fregnan, Federica; Geuna, Stefano; Sinis, Nektarios

2014-01-01

302

Model-based analysis and design of nerve cuff electrodes for restoring bladder function by selective stimulation of the pudendal nerve  

NASA Astrophysics Data System (ADS)

Objective. Electrical stimulation of the pudendal nerve (PN) is being developed as a means to restore bladder function in persons with spinal cord injury. A single nerve cuff electrode placed on the proximal PN trunk may enable selective stimulation of distinct fascicles to maintain continence or evoke micturition. The objective of this study was to design a nerve cuff that enabled selective stimulation of the PN. Approach. We evaluated the performance of both flat interface nerve electrode (FINE) cuff and round cuff designs, with a range of FINE cuff heights and number of contacts, as well as multiple contact orientations. This analysis was performed using a computational model, in which the nerve and fascicle cross-sectional positions from five human PN trunks were systematically reshaped within the nerve cuff. These cross-sections were used to create finite element models, with electric potentials calculated and applied to a cable model of a myelinated axon to evaluate stimulation selectivity for different PN targets. Subsequently, the model was coupled to a genetic algorithm (GA) to identify solutions that used multiple contact activation to maximize selectivity and minimize total stimulation voltage. Main results. Simulations did not identify any significant differences in selectivity between FINE and round cuffs, although the latter required smaller stimulation voltages for target activation due to preserved localization of targeted fascicle groups. Further, it was found that a ten contact nerve cuff generated sufficient selectivity for all PN targets, with the degree of selectivity dependent on the relative position of the target within the nerve. The GA identified solutions that increased fitness by 0.7-45.5% over single contact activation by decreasing stimulation of non-targeted fascicles. Significance. This study suggests that using an optimal nerve cuff design and multiple contact activation could enable selective stimulation of the human PN trunk for restoration of bladder function.

Kent, Alexander R.; Grill, Warren M.

2013-06-01

303

Anterograde transneuronal viral tract tracing reveals central sensory circuits from brown fat and sensory denervation alters its thermogenic responses  

PubMed Central

Brown adipose tissue (BAT) thermogenic activity and growth are controlled by its sympathetic nervous system (SNS) innervation, but nerve fibers containing sensory-associated neuropeptides [substance P, calcitonin gene-related peptide (CGRP)] also suggest sensory innervation. The central nervous system (CNS) projections of BAT afferents are unknown. Therefore, we used the H129 strain of the herpes simplex virus-1 (HSV-1), an anterograde transneuronal viral tract tracer used to delineate sensory nerve circuits, to define these projections. HSV-1 was injected into interscapular BAT (IBAT) of Siberian hamsters and HSV-1 immunoreactivity (ir) was assessed 24, 48, 72, 96, and 114 h postinjection. The 96- and 114-h groups had the most HSV-1-ir neurons with marked infections in the hypothalamic paraventricular nucleus, periaqueductal gray, olivary areas, parabrachial nuclei, raphe nuclei, and reticular areas. These sites also are involved in sympathetic outflow to BAT suggesting possible BAT sensory-SNS thermogenesis feedback circuits. We tested the functional contribution of IBAT sensory innervation on thermogenic responses to an acute (24 h) cold exposure test by injecting the specific sensory nerve toxin capsaicin directly into IBAT pads and then measuring core (Tc) and IBAT (TIBAT) temperature responses. CGRP content was significantly decreased in capsaicin-treated IBAT demonstrating successful sensory nerve destruction. TIBAT and Tc were significantly decreased in capsaicin-treated hamsters compared with the saline controls at 2 h of cold exposure. Thus the central sensory circuits from IBAT have been delineated for the first time, and impairment of sensory feedback from BAT appears necessary for the appropriate, initial thermogenic response to acute cold exposure. PMID:22378771

Vaughan, Cheryl H.

2012-01-01

304

Video analysis of standing — an alternative footprint analysis to assess functional loss following injury to the rat sciatic nerve  

Microsoft Academic Search

The rat sciatic nerve is a well-established animal model for the study of recovery from peripheral nerve injuries. Footprint analysis is the most widely used non-invasive method of measuring functional recovery after injury in this model. We describe a new alternative video analysis of standing (or static footprint video analysis) to assess functional loss following injury to the rat sciatic

Marijan Bervar

2000-01-01

305

Nerve function and dysfunction in acute intermittent porphyria.  

PubMed

Acute intermittent porphyria (AIP) is a rare metabolic disorder characterized by mutations of the porphobilinogen deaminase gene. Clinical manifestations of AIP are caused by the neurotoxic effects of increased porphyrin precursors, although the underlying pathophysiology of porphyric neuropathy remains unclear. To further investigate the neurotoxic effect of porphyrins, excitability measurements (stimulus-response, threshold electrotonus, current-threshold relationship and recovery cycle) of peripheral motor axons were undertaken in 20 AIP subjects combined with the results of genetic screening, biochemical and conventional nerve conduction studies. Compared with controls, excitability measurements from five latent AIP patients were normal, while 13 patients who experienced acute porphyric episodes without clinical neuropathy (AIPWN) showed clear differences in their responses to hyperpolarizing currents (e.g. reduced hyperpolarizing I/V slope, P < 0.01). Subsequent mathematical simulation using a model of human axons indicated that this change could be modelled by a reduction in the hyperpolarization-activated, cyclic nucleotide-dependent current (I(H)). In contrast, in one patient tested during an acute neuropathic episode, axons of high threshold with reduced superexcitability, consistent with membrane depolarization and reminiscent of ischemic changes. It is proposed that porphyrin neurotoxicity causes a subclinical reduction in I(H) in AIPWN axons, whereas porphyric neuropathy may develop when reduced activity of the Na(+)/K(+) pump results in membrane depolarization. PMID:18669508

Lin, Cindy S-Y; Krishnan, Arun V; Lee, Ming-Jen; Zagami, Alessandro S; You, Hui-Ling; Yang, Chih-Chao; Bostock, Hugh; Kiernan, Matthew C

2008-09-01

306

Structure/Function assessment of synapses at motor nerve terminals  

PubMed Central

The release of transmitter at neuromuscular junctions (NMJ) of the opener muscle in crayfish is quantal in nature. This NMJ offers the advantage of being able to record quantal events at specific visually identified release sites, thus allowing measurement of the physiological parameters of vesicle release and its response to be directly correlated with synaptic structure. These experiments take advantage of areas between the varicosities on the nerve terminal that we define as “stems”. Stems were chosen as the region to study because of their low synaptic output due to fewer synaptic sites. Through 3-D reconstruction from hundreds of serial sections, obtained by transmission electron microscopy (TEM), at a site in which focal macropatch recordings were obtained, the number of synapses and AZs are revealed. Thus, physiological profiles with various stimulation conditions can be assessed in regards to direct synaptic structure. Here we used the properties of the quantal shape to determine if distinct subsets of quantal signatures existed and if differences in the distributions are present depending on the frequency of stimulation. Such a quantal signature could come about by parameters of area, rise time, peak amplitude, latency and tau decay. In this study, it is shown that even at defined sites on the stem, with few active zones, synaptic transmission is still complex and the quantal responses appear to be variable even for a given synapse over time. In this study we could not identify a quantal signature for the conditions utilized. PMID:20730805

Johnstone, A. F. M.; Viele, K.; Cooper, R. L.

2010-01-01

307

Functional regeneration of severed peripheral nerve using an implantable electrical stimulator  

Microsoft Academic Search

This paper presents functional regeneration of severed peripheral nerve using a polymer-based implantable electrical stimulator. A polyimide based conduit electrode was made by micro-fabrication and a stimulation chip was designed to generate biphasic current pulse for electrical stimulation. The stimulation chip was packaged with a battery using silicone elastomer, and integrated with the electrode. The implantable electrical stimulator was implanted

Tae Hyung Lee; Hui Pan; In Sook Kim; Soon Jung Hwang; S. J. Kim

2010-01-01

308

Nimodipine Accelerates Functional Recovery of the Facial Nerve after Crush Injury  

PubMed Central

Objective To establish whether nimodipine, a calcium channel blocker, accelerates or otherwise improves functional recovery of whisking after facial nerve crush injury in the rat. Methods Thirty rats underwent exposure of the left main trunk of the facial nerve followed by a standard crush injury, and subsequent quantitative facial movement testing. Animals were randomized into an experimental group (n=15) and a control group (n=15 each). Four days prior to facial nerve manipulation, experimental animals underwent subcutaneous implantation of a nimodipine-secreting pellet. All animals were tested pre-operatively and on post-crush days 2, 8–17, 20, 22, 24, and 31, using a validated, quantitative whisking kinematics apparatus. Whisks were analyzed for amplitude, velocity, and acceleration. Results Animals receiving nimodipine demonstrated significantly better whisking on days 9, 11–13, and 20 compared with control animals (p<.05). Overall, the nimodipine-treated animals showed earlier recovery as compared to the untreated animals. Conclusions We demonstrate that nimodipine improves recovery of whisking after facial nerve crush. This finding corroborates the semi-quantitative findings of others, and provides complete whisking kinematic data on its effects. Given the low side effect profile of nimodipine, there may be clinical implications in its administration in patients experiencing facial nerve injury. PMID:20083741

Lindsay, Robin W.; Heaton, James T.; Edwards, Colin; Smitson, Christoper; Hadlock, Tessa A.

2015-01-01

309

Bradykinin Controls Pool Size of Sensory Neurons Expressing Functional ?-Opioid Receptors  

PubMed Central

Analgesics targeting the ?-opioid receptor (DOR) may lead to fewer side effects than conventional opioid drugs, which mainly act on ?-opioid receptors (MOR), because of the less abundant expression of DOR in the CNS compared with MOR. Analgesic potential of DOR agonists increases after inflammation, an effect that may be mediated by DOR expressed in the peripheral sensory fibers. However, the expression of functional DOR at the plasma membrane of sensory neurons is controversial. Here we have used patch-clamp recordings and total internal reflection fluorescence microscopy to study the functional expression of DOR in sensory neurons from rat trigeminal (TG) and dorsal root ganglia (DRG). Real-time total internal reflection fluorescence microscopy revealed that treatment of TG and DRG cultures with the inflammatory mediator bradykinin (BK) caused robust trafficking of heterologously expressed GFP-tagged DOR to the plasma membrane. By contrast, treatment of neurons with the DOR agonist [d-Ala2, d-Leu5]-enkephalin (DADLE) caused a decrease in the membrane abundance of DOR, suggesting internalization of the receptor after agonist binding. Patch-clamp experiments revealed that DADLE inhibited voltage-gated Ca2+ channels (VGCCs) in 23% of small-diameter TG neurons. Pretreatment with BK resulted in more than twice as many DADLE responsive neurons (54%) but did not affect the efficacy of VGCC inhibition by DADLE. Our data suggest that inflammatory mediator-induced membrane insertion of DOR into the plasma membrane of peripheral sensory neurons may underlie increased DOR analgesia in inflamed tissue. Furthermore, the majority of BK-responsive TG neurons may have a potential to become responsive to DOR ligands in inflammatory conditions. PMID:23804098

Pettinger, Louisa; Gigout, Sylvain; Linley, John E.

2013-01-01

310

Bradykinin controls pool size of sensory neurons expressing functional ?-opioid receptors.  

PubMed

Analgesics targeting the ?-opioid receptor (DOR) may lead to fewer side effects than conventional opioid drugs, which mainly act on ?-opioid receptors (MOR), because of the less abundant expression of DOR in the CNS compared with MOR. Analgesic potential of DOR agonists increases after inflammation, an effect that may be mediated by DOR expressed in the peripheral sensory fibers. However, the expression of functional DOR at the plasma membrane of sensory neurons is controversial. Here we have used patch-clamp recordings and total internal reflection fluorescence microscopy to study the functional expression of DOR in sensory neurons from rat trigeminal (TG) and dorsal root ganglia (DRG). Real-time total internal reflection fluorescence microscopy revealed that treatment of TG and DRG cultures with the inflammatory mediator bradykinin (BK) caused robust trafficking of heterologously expressed GFP-tagged DOR to the plasma membrane. By contrast, treatment of neurons with the DOR agonist [d-Ala(2), d-Leu(5)]-enkephalin (DADLE) caused a decrease in the membrane abundance of DOR, suggesting internalization of the receptor after agonist binding. Patch-clamp experiments revealed that DADLE inhibited voltage-gated Ca(2+) channels (VGCCs) in 23% of small-diameter TG neurons. Pretreatment with BK resulted in more than twice as many DADLE responsive neurons (54%) but did not affect the efficacy of VGCC inhibition by DADLE. Our data suggest that inflammatory mediator-induced membrane insertion of DOR into the plasma membrane of peripheral sensory neurons may underlie increased DOR analgesia in inflamed tissue. Furthermore, the majority of BK-responsive TG neurons may have a potential to become responsive to DOR ligands in inflammatory conditions. PMID:23804098

Pettinger, Louisa; Gigout, Sylvain; Linley, John E; Gamper, Nikita

2013-06-26

311

Dual Sensory Loss and Depressive Symptoms: The Importance of Hearing, Daily Functioning, and Activity Engagement  

PubMed Central

Background: The association between dual sensory loss (DSL) and mental health has been well established. However, most studies have relied on self-report data and lacked measures that would enable researchers to examine causal pathways between DSL and depression. This study seeks to extend this research by examining the effects of DSL on mental health, and identify factors that explain the longitudinal associations between sensory loss and depressive symptoms. Methods: Piecewise linear-mixed models were used to analyze 16-years of longitudinal data collected on up to five occasions from 1611 adults (51% men) aged between 65 and 103?years. Depressive symptoms were assessed by the Centre for Epidemiological Studies Depression (CES-D). Vision loss (VL) was defined by corrected visual acuity >0.3 logMAR in the better eye, blindness, or glaucoma. Hearing loss (HL) was defined by pure-tone average (PTA) >25?dB in the better hearing ear. Analyses were adjusted for socio-demographics, medical conditions, lifestyle behaviors, activities of daily living (ADLs), cognitive function, and social engagement. Results: Unadjusted models indicated that higher levels of depressive symptoms were associated with HL (B?=?1.16, SE?=?0.33) and DSL (B?=?2.15, SE?=?0.39) but not VL. Greater rates of change in depressive symptoms were also evident after the onset of HL (B?=?0.16, SE?=?0.06, p?sensory loss were explained by difficulties with ADLs, and social engagement. Conclusion: Vision and HL are highly prevalent among older adults and their co-occurrence may compound their respective impacts on health, functioning, and activity engagement, thereby exerting strong effects on the mental health and wellbeing of those affected. There is therefore a need for rehabilitation programs to be sensitive to the combined effects of sensory loss on individuals. PMID:24379769

Kiely, Kim M.; Anstey, Kaarin J.; Luszcz, Mary A.

2013-01-01

312

Supporting sensory transduction: cochlear fluid homeostasis and the endocochlear potential  

Microsoft Academic Search

The exquisite sensitivity of the cochlea, which mediates the transduction of sound waves into nerve impulses, depends on the endocochlear potential and requires a highly specialized environment that enables and sustains sensory function. Disturbance of cochlear homeostasis is the cause of many forms of hearing loss including the most frequently occurring syndromic and non-syndromic forms of hereditary hearing loss, Pendred

Philine Wangemann

2006-01-01

313

[Microneural reconstruction after iatrogenic lesions of the lingual nerve and the inferior alveolar nerve. Critical evaluation].  

PubMed

As microneural repair techniques of the sensory mandibular branches enter the third decade of their clinical use, there are but a few long-term investigations into the value of these procedures in the treatment of iatrogenic injury to the lingual (LN), inferior alveolar (IAN) or mental (MN) nerve. To establish the efficacy of microneural repair in lesions of the LN, IAN or MN with loss of continuity, the outcome of sensory recovery was evaluated in a series of 92 patients (LN: direct coaptation n = 39, coaptation + sural nerve grafting n = 23; IAN: direct coaptation n = 11 coaptation + sural nerve grafting n = 10; MN: direct coaptation n = 11). The minimum duration of follow-up was 14 months postoperatively. The persistent sensory deficit was assessed using standardized neurosensory testing and gustometric stimuli. In addition the patients answered a multiple-choice questionnaire containing a list of complaints. To obtain a numeric estimate for interindividual and intergroup comparison the information from clinical measurements and patient reports was condensed into a 'neurological score' and a 'complaint score', respectively. Furthermore, adequate items from both scores were combined to affirm or deny the return of sensory function in terms of protective and discriminative sensation. The overall results show a broad range of variation in the scores, sometimes reflecting severe degrees of persistent sensory impairment. The lowest scores, corresponding to the best regeneration, were found after direct coaptation of the LN, IAN and NM, but even the best results did not provide sensory recovery to a preinjury level. After direct coaptation of LN 69% of the patients exhibited protective sensation and 41% regained discriminative function. In contrast, LN grafting was ensued from restoration of protective function in 39% and discriminative function in 17% of the patients. More striking differences were found between coaptation and grafting of the IAN (IAN coaptation: 91% protective function; 18% discriminative function; IAN grafting: 60% protective function, 0% discriminative function). In the LN coaptation group low scores and improved taste perception were convincingly associated with short periods since injury (i.e. timing of repair). In conclusion, we feel there is sufficient justification to optimize the potential results of microneural repair by immediate (LN/MN) or early (IAN) reexposure of the injured site in order to clarify the precise nature of the underlying nerve damage and prevent delay, if patients present with complete loss of sensory function subsequent to dentoalveolar or oral surgery. However, clinical and electrophysiologic findings suggesting impairment or partial loss of sensory function are considered a contraindication to microneural intervention, in view of the limited prospects of sensory recovery after surgical repair. PMID:9410631

Cornelius, C P; Roser, M; Ehrenfeld, M

1997-07-01

314

Bioenergetic deficits in peripheral nerve sensory axons during chemotherapy-induced neuropathic pain resulting from peroxynitrite-mediated post-translational nitration of mitochondrial superoxide dismutase.  

PubMed

Many of the widely used anticancer drugs induce dose-limiting peripheral neuropathies that undermine their therapeutic efficacy. Animal models of chemotherapy-induced painful peripheral neuropathy (CIPN) evoked by a variety of drug classes, including taxanes, vinca alkaloids, platinum-complexes, and proteasome-inhibitors, suggest that the common underlying mechanism in the development of these neuropathies is mitotoxicity in primary nerve sensory axons (PNSAs) arising from reduced mitochondrial bioenergetics [eg adenosine triphosphate (ATP) production deficits due to compromised respiratory complex I and II activity]. The causative mechanisms of this mitotoxicity remain poorly defined. However, peroxynitrite, an important pro-nociceptive agent, has been linked to mitotoxicity in several disease states and may also drive the mitotoxicity associated with CIPN. Our findings reveal that the development of mechano-hypersensitivity induced by paclitaxel, oxaliplatin, and bortezomib was prevented by administration of the peroxynitrite decomposition catalyst Mn(III) 5,10,15,20-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin (MnTE-2-PyP(5+)) without interfering with their anti-tumor effects. Peak CIPN was associated with the nitration and inactivation of superoxide dismutase in the mitochondria, but not in the cytosol, as well as a significant decrease in ATP production within the PNSAs; all of these events were attenuated by MnTE-2-PyP(5+). Our results provide continued support for the role of mitotoxicity in the development of CIPN across chemotherapeutic drug classes, and identify peroxynitrite as a key mediator in these processes, thereby providing the rationale towards development of "peroxynitrite-targeted" therapeutics for CIPN. PMID:23891899

Janes, Kali; Doyle, Timothy; Bryant, Leesa; Esposito, Emanuela; Cuzzocrea, Salvatore; Ryerse, Jan; Bennett, Gary J; Salvemini, Daniela

2013-11-01

315

Nerve growth factor, glial cell line-derived neurotrophic factor and neurturin prevent semaphorin 3A-mediated growth cone collapse in adult sensory neurons.  

PubMed

Developmentally, semaphorin 3A (sema3A) is an important chemorepellent that guides centrally projecting axons of dorsal root ganglion (DRG) neurons. Sema3A-mediated growth cone collapse can be prevented by cyclic GMP (cGMP) and nerve growth factor (NGF) in embryonic neurons. Sema3A may also play a role in directing regrowth of injured axons in adults, and interactions with neurotrophic factors near the injury site may determine the extent and targeting of both regenerative and aberrant growth. The aim of this study was to determine whether NGF, glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) modulate sema3A-mediated growth cone collapse in cultured adult rat DRG neurons. Sema3A caused a significant increase in growth cone collapse, which was completely prevented by prior treatment with NGF, GDNF or NTN. Immunocytochemical experiments showed that sema3A-sensitive neurons were heterogeneous in their expression of neurotrophic factor receptors and responses to neurotrophic factors, raising the possibility of novel, convergent signaling mechanisms between these substances. Increasing cGMP levels caused growth cone collapse, whereas sema3A-mediated collapse was prevented by inhibition of guanylate cyclase or by increasing cyclic AMP levels. In conclusion, sema3A signaling pathways in adult neurons differ to those described in embryonic neurons. Three different neurotrophic factors each completely prevent sema3A-mediated collapse, raising the possibility of novel converging signaling pathways. These studies also show that there is considerable potential for neurotrophic factors to regulate sema3A actions in the adult nervous system. This may provide insights into the mechanisms underling misdirected growth and targeting of sensory fibers within the spinal cord after injury, that is thought to contribute to development of autonomic dysreflexia and neuropathic pain. PMID:16876331

Wanigasekara, Y; Keast, J R

2006-10-13

316

Morphological and functional evaluation of leg-muscle reinnervation after coupler coaptation of the divided rat sciatic nerve.  

PubMed

Mechanical couplers are successfully used for microvascular venous anastomoses. The advantages include a simple and fast technique and a high patency rate. Couplers offer a secluded coaptation site, and might also be of use in peripheral nerve repair. The present study was designed to investigate coupler coaptation of the rat sciatic nerve, evaluating the number and locations of motor and sensory neurons projecting to the selected muscles as well as stimulation-induced muscle contraction force. Adult rats underwent either suture or coupler repair after left sciatic nerve transection. In all rats, the experimental side was compared to the healthy right side. Evaluation after 20 weeks included retrograde labeling of motoneurons and dorsal root ganglion neurons projecting to the tibial anterior muscle and to the tibial posterior muscle, histology, muscle contraction force (tibial anterior muscle and gastrocnemius muscle), and a pinch reflex test. The results show that the suture and the coupler groups did not differ significantly regarding the examined parameters, except for discrete signs of nerve compression at the coaptation site after coupler repair due to fibrous tissue ingrowth. However, this did not impair axonal regeneration. Importantly, axonal outgrowth from the repair site to the surrounding tissue was not observed after coupler coaptation, but it was observed after suture repair. These results suggest that couplers may be of value for repair of nerves in adjacency to avoid axonal crisscrossing between nerves during regeneration. PMID:15696517

Lutz, Barbara S; Lidman, Disa

2005-01-01

317

[Applications of 'quantitative sensory testing'].  

PubMed

Quantitative sensory testing (QST) consists of several non-invasive, standardised tests aimed at examining different aspects of the entire somatosensory nervous system. Important advantages of QST over existing supplementary tests such as electromyography are the ability to test the function of thin and unmyelinated nerve fibres as well as the subjective sensation of a somatosensory stimulus. QST is validated in diagnosing small fibre neuropathy, diabetic neuropathy chemotherapy-induced peripheral neuropathy and neuropathic pain. In scientific research, QST is useful in the study into pathophysiological mechanisms of diseases and syndromes with sensory symptoms and in the evaluation of the effect of analgesic treatment on the function of the somatosensory nervous system. In the future, QST could be a useful diagnostic and prognostic test in more forms of neuropathy and in other clinical conditions such as chronic unexplained pain syndromes (e.g. fibromyalgia and whiplash-associated disorder. PMID:23369816

Verberne, Wouter R; Snijders, Tom J; Liem, K Seng; Baakman, Anne Catrien; Veldhuijzen, Dieuwke S

2013-01-01

318

Effect of combined nicotine and shrapnel exposure on pain measures and gait after nerve injury.  

PubMed

A significant fraction of military soldiers sustain nerve injury and use tobacco or nicotine containing products. Healing of nerve injuries is influenced by many factors, such as degree of original injury, healing potential of the nerve, and general health of patient. However, recently, it has been demonstrated that the presence of retained insoluble metal fragments decreases healing. The effects of systemic nicotine administration, with or without metal fragments at the site of nerve injury, were evaluated. Both the nicotine-administered groups (nicotine, nicotine + shrapnel) showed significant increase in the peroneal function compared with untreated controls, as assessed by paw area (p < 0.05). Furthermore, to test possible role of altered sensory function, we used the hot plate assay. Latency to withdraw paw from a hot plate was significantly shorter in nicotine groups (p < 0.05). These data indicate that nicotine improves sensory and motor aspects of nerve function, in the presence or absence of shrapnel. PMID:22165666

Rittenhouse, Bradley; Hill-Pryor, Crystal D; McConathy, Adam; Parker, Peter; Franco, Nelson; Toussaint, Esra; Barker, Darrell; Prasad, Balakrishna; Pizarro, Jose M

2011-11-01

319

Dual Regulation of ?-Opioid Receptor Function by Arachidonic Acid Metabolites in Rat Peripheral Sensory Neurons.  

PubMed

The regulation of opioid receptor system function in peripheral sensory neurons is not well understood. Opioid agonist efficacy to inhibit nociceptor function and to promote antinociception is generally weak under basal conditions and frequently no response occurs. However, in response to a cyclooxygenase-dependent metabolite of arachidonic acid (AA) after exposure to inflammatory mediators, such as bradykinin (BK) or exogenous AA, peripheral opioid receptor systems become much more responsive to opioid agonists. In this study, we examined the time course for the induction and maintenance of functional competence of the ?-opioid receptor (DOR) system in adult rat nociceptors in culture and in vivo. We found that the responsive state of DOR after pretreatment with BK or exogenous AA is transient (30-60 minutes) and persists for 15-30 minutes after a 15-minute exposure of nociceptors to BK or AA. Interestingly, whereas functional competence of the DOR system could be reinduced with a second application of BK 60 minutes after the first, responsiveness of the DOR system could not be reinduced after an initial exposure to AA. This nonresponsive state of DOR after exogenous AA was mediated by a lipoxygenase (LOX)-dependent metabolite of AA. Intraplantar carrageenan also produced transient DOR functional competence and responsiveness was also reinduced by inhibition of LOX. Thus, the DOR system expressed by peripheral sensory neurons is under dual regulation by cyclooxygenase- and LOX-dependent metabolites of AA. PMID:25637601

Sullivan, Laura C; Berg, Kelly A; Clarke, William P

2015-04-01

320

Measurement of integrated sensory-motor function following brain damage by a computerized preview tracking task.  

PubMed

A preview tracking task has been developed which has particular application to neurological assessment and rehabilitation. Generated and monitored by a graphic display computer, it permits accurate global quantification of the upper-limb sensory-motor system. The incorporation of 'preview' into the tracking task is considered to significantly increase its effectiveness and relevance in relation to normal daily activities. Applied to three groups of normal subjects, several features of normal psychomotor performance and learning were identified or verified: hand dominance is not significant in overall arm control; learning does not completely plateau; increase in age (15-59 years) results in only a minor overall decrement in performance; an initial wide performance distribution decreases dramatically in subsequent sessions. Applied to brain-damaged patients, particularly head injury or stroke, the preview tracking task allows assessment at regular intervals enabling sensory-motor recovery curves to be generated. The potential of this technique, to help determine the efficacy of therapeutic procedures on the recovery process, is illustrated with the presentation of results from three brain-damaged patients demonstrating zero, significant and disjointed recovery of sensory-motor function. The usefulness of the preview tracking task can be expanded by combination with a less frequently applied but more component specific neurological assessment battery. PMID:7309401

Jones, R D; Donaldson, I M

1981-01-01

321

The role of the gastric afferent vagal nerve in ghrelin-induced feeding and growth hormone secretion in rats  

Microsoft Academic Search

Background & Aims: Visceral sensory information is transmitted to the brain through the afferent vagus nerve. Ghrelin, a peptide primarily produced in the stomach, stimulates both feeding and growth hormone (GH) secretion. How stomach-derived ghrelin exerts these central actions is still unknown. Here we determined the role of the gastric afferent vagal nerve in ghrelin's functions. Methods: Food intake and

Yukari Date; Noboru Murakami; Koji Toshinai; Shigeru Matsukura; Akira Niijima; Hisayuki Matsuo; Kenji Kangawa; Masamitsu Nakazato

2002-01-01

322

Concurrent functional magnetic resonance imaging and electroencephalography assessment of sensory gating in schizophrenia  

PubMed Central

Schizophrenia is frequently accompanied by deficits in basic information processing, such as sensory gating. The sources behind deficient sensory gating in schizophrenia patients are, however, still largely unclear. The aim of the current study was to identify the brain structures involved in deficient sensory gating in schizophrenia patients. Twenty healthy male volunteers and 23 male schizophrenia patients were initially assessed in a somatosensory P50 suppression paradigm using concurrent electroencephalography (EEG)/functional magnetic resonance imaging (fMRI) methodology. The trials consisted of single stimuli or pairs of identical stimuli with either 500 ms or 1,000 ms interstimulus intervals. Not all subjects showed a P50 waveform as a result of the somatosensory stimuli: It was detected in 13 schizophrenia patients and 15 control subjects. Significant P50 suppression was found in the 500 ms trials in controls only. Region of interest analyses were performed for a priori chosen regions. Significant negative correlations between P50 ratios and the BOLD response were found bilaterally in the hippocampus, thalamus, anterior and posterior superior temporal gyrus (STG), and in the left inferior frontal gyrus pars opercularis. However, significant group differences were found in the hippocampus and the thalamus only. This is the first study in which P50 suppression was assessed in schizophrenia patients with concurrent fMRI/EEG methodology. The data support that the STG, thalamus, inferior frontal gyrus, and the hippocampus are involved in P50 suppression. However, of these structures only the hippocampus and thalamus appeared involved in the altered sensory processing found in schizophrenia. Hum Brain Mapp 35:3578–3587, 2014. © 2013 Wiley Periodicals, Inc. PMID:24375687

Bak, Nikolaj; Rostrup, Egill; Larsson, Henrik BW; Glenthřj, Birte Y; Oranje, Bob

2014-01-01

323

Clinical consequences of reinnervation disorders after focal peripheral nerve lesions.  

PubMed

Axonal regeneration and organ reinnervation are the necessary steps for functional recovery after a nerve lesion. However, these processes are frequently accompanied by collateral events that may not be beneficial, such as: (1) Uncontrolled branching of growing axons at the lesion site. (2) Misdirection of axons and target organ reinnervation errors, (3) Enhancement of excitability of the parent neuron, and (4) Compensatory activity in non-damaged nerves. Each one of those possible problems or a combination of them can be the underlying pathophysiological mechanism for some clinical conditions seen as a consequence of a nerve lesion. Reinnervation-related motor disorders are more likely to occur with lesions affecting nerves which innervate muscles with antagonistic functions, such as the facial, the laryngeal and the ulnar nerves. Motor disorders are better demonstrated than sensory disturbances, which might follow similar patterns. In some instances, the available examination methods give only scarce evidence for the positive diagnosis of reinnervation-related disorders in humans and the diagnosis of such condition can only be based on clinical observation. Whatever the lesion, though, the restitution of complex functions such as fine motor control and sensory discrimination would require not only a successful regeneration process but also a central nervous system reorganization in order to integrate the newly formed peripheral nerve structure into the prepared motor programs and sensory patterns. PMID:20656551

Valls-Sole, Josep; Castillo, Carlos David; Casanova-Molla, Jordi; Costa, Joao

2011-02-01

324

Improved regeneration after femoral nerve injury in mice lacking functional T- and B-lymphocytes.  

PubMed

The immune system plays important functional roles in regeneration after injury to the mammalian central and peripheral nervous systems. After damage to the peripheral nerve several types of immune cells, invade the nerve within hours after the injury. To gain insights into the contribution of T- and B-lymphocytes to recovery from injury we used the mouse femoral nerve injury paradigm. RAG2-/- mice lacking mature T- and B-lymphocytes due to deletion of the recombination activating gene 2 were subjected to resection and surgical reconstruction of the femoral nerve, with the wild-type mice of the same inbred genetic background serving as controls. According to single frame motion analyses, RAG2-/- mice showed better motor recovery in comparison to control mice at four and eight weeks after injury. Retrograde tracing of regrown/sprouted axons of spinal motoneurons showed increased numbers of correctly projecting motoneurons in the lumbar spinal cord of RAG2-/- mice compared with controls. Whereas there was no difference in the motoneuron soma size between genotypes, RAG2-/- mice displayed fewer cholinergic and inhibitory synaptic terminals around somata of spinal motoneurons both prior to and after injury, compared with wild-type mice. Extent of myelination of regrown axons in the motor branch of the femoral nerve measured as g-ratio was more extensive in RAG2-/- than in control mice eight weeks after injury. We conclude that activated T- and B-lymphocytes restrict motor recovery after femoral nerve injury, associated with the increased survival of motoneurons and improved remyelination. PMID:24967682

Mehanna, Ali; Szpotowicz, Emanuela; Schachner, Melitta; Jakovcevski, Igor

2014-11-01

325

Esophagoprotective activity of angiotensin-(1-7) in experimental model of acute reflux esophagitis. Evidence for the role of nitric oxide, sensory nerves, hypoxia-inducible factor-1alpha and proinflammatory cytokines.  

PubMed

Gastroesophageal reflux disease (GERD) is a global disease rapidly increasing among world population. The pathogenesis of reflux esophagitis which is considered as the early stage of GERD is complex, resulting from an imbalance between aggressive factors damaging the esophagus and a number of the natural defense mechanisms. The esophageal mucosa is in a state of continuous exposure to potentially damaging endogenous and exogenous factors. Important aggressive components of gastric refluxate include acid and pepsin and also pancreatic enzymes and bile. Among aggressive factors of exogenous origin, cigarette smoking, non-steroidal anti-inflammatory drugs (NSAID), and steroids are of the utmost importance. The basic level of esophageal defense against acid-pepsin damage consists of the anti-reflux mechanisms such as the luminal acid clearance and removal of the esophageal contents and neutralization of luminal acidity. In addition the esophageal mucosal protection includes the presence of pre-epithelial, epithelial and post-epithelial cellular and functional components. Recently, the progress have been made in the understanding of role of the heptapeptide member of the renin-angiotensin system (RAS), angiotensin-(1-7) (Ang-(1-7)) in the control of gastrointestinal functions. It has been shown that all components of local RAS including Ang-(1-7) are detectable in the gastrointestinal wall including not only the stomach but also the esophagus. Previous studies revealed that Ang-(1-7), which is an important component of the RAS, exerts vasodilatory, anti-inflammatory and antioxidant activities in the stomach. Ang-(1-7) was recently implicated in gastroprotection, but its effects on esophageal mucosa in a rodent model of reflux esophagitis and in human subjects presenting GERD symptoms have not been explored. The present study was aimed to evaluate the possible protective effects of Ang-(1-7) and Mas-receptors upon esophageal mucosal damage in acute reflux esophagitis (RE) induced in anesthetized rats by ligating the pylorus and the limiting ridge (a transitional region between the forestomach and the corpus of stomach). Consequently, the total gastric reservoir to store gastric juice was greatly diminished, resulting in the reflux of this juice into the esophagus. Because Mas receptors are functionally linked to nitric oxide (NO) formation, we also studied involvement of endogenous NO in the mediation of protective and circulatory effects of exogenous Ang-(1-7). Moreover, an attempt was made to assess the possible role of sensory neurons in the modulation of the protective effects exerted by Ang-(1-7)/Mas receptor system. Six series of rats were pretreated 30 min before induction of RE with 1) vehicle (saline), 2) Ang-(1-7) (5-50 ?g/kg i.p.), 3) A779 (50 ?g/kg i.p.), the selective Mas receptor antagonist applied alone, 4) Ang-(1-7) (50 ?g/kg i.p.) combined with A779, 5) L-NNA (20 mg/kg i.p.) administered alone, and 6) Ang-(1-7) (50 ?g/kg i.p.) combined with L-NNA. In separate group of rats, capsaicin (total dosage of 125 mg/kg within three days) was administered s.c. 2 weeks before the induction of RE to induce functional ablation of sensory nerves. Rats with intact sensory nerves and those with capsaicin-induced sensory denervation received vehicle (saline) or Ang-(1-7) (50 ?g/kg i.p.) to determine whether this vasoactive metabolite of angiotensin I could be also effective in rats with capsaicin-induced impairment of the synthesis and release of sensory neuropeptides such as CGRP. Four hours after induction of RE, the mucosal damage was graded with mucosal lesion index (LI) from 0 to 6, the esophageal microcirculatory blood flow (EBF) was determined by H2-gas clearance technique and plasma level of pro-inflammatory cytokines interleukin-1b (IL-1?), and tumor necrosis factor-? (TNF-?) was determined by ELISA. The expression of proinflammatory factors including COX-2, cytokine IL-1? and hypoxia inducible factor 1alpha (Hif1?) was analyzed in the esophageal mucosal biopsies. In rats with RE, the esophageal LI was signi

Pawlik, M W; Kwiecien, S; Pajdo, R; Ptak-Belowska, A; Brzozowski, B; Krzysiek-Maczka, G; Strzalka, M; Konturek, S J; Brzozowski, T

2014-12-01

326

Subthreshold continuous electrical stimulation facilitates functional recovery of facial nerve after crush injury in rabbit.  

PubMed

We sought to determine whether electrical stimulation (ES) with subthreshold, continuous, low-frequency impulses is a viable clinical method for improving functional recovery after facial nerve crush injury. In 10 rabbits, bilateral crush injuries were made on the facial nerve by compression for 30 s with mosquito forceps, causing complete facial paralysis. Subthreshold continuous direct current ES with 20-Hz square-wave pulses was applied to the proximal stump on one side for 4 weeks. Vibrissae movement returned significantly earlier on the ES side, with a less variable recovery time. Electrophysiologically, the stimulated side had a significantly shorter latency, longer duration, and faster conduction velocity. Light and transmission electron microscopy revealed that the electrical stimulation also markedly decreased Wallerian degeneration. The average numbers of fluorescent, double-labeled nerve cells were significantly different between the ES and non-ES sides. This study shows that subthreshold, continuous, low-frequency ES immediately after a crush injury of the facial nerve results in earlier recovery of facial function and shorter overall recovery time. PMID:21254091

Kim, Jin; Han, Su Jin; Shin, Dong Hyun; Lee, Won-Sang; Choi, Jae Young

2011-02-01

327

Axonal degeneration of the ulnar nerve secondary to carpal tunnel syndrome: fact or fiction?  

PubMed

The distribution of sensory symptoms in carpal tunnel syndrome is strongly dependent on the degree of electrophysiological dysfunction of the median nerve. The association between carpal tunnel syndrome and ulnar nerve entrapment is still unclear. In this study, we measured ulnar nerve function in 82 patients with carpal tunnel syndrome. The patients were divided into group I with minimal carpal tunnel syndrome (n = 35) and group II with mild to moderate carpal tunnel syndrome (n = 47) according to electrophysiological data. Sixty-one age- and sex-matched subjects without carpal tunnel syndrome were used as a control group. There were no significant differences in ulnar sensory nerve peak latencies or conduction velocities from the 4(th) and 5(th) fingers between patients with carpal tunnel syndrome and the control group. The ulnar sensory nerve action potential amplitudes from the 4(th) and 5(th) fingers were lower in patients with carpal tunnel syndrome than in the control group. The ratios of the ulnar sensory nerve action potential amplitudes from the 4(th) and 5(th) fingers were almost the same in patients with carpal tunnel syndrome as in the control group. These findings indicate that in patients with minimal to moderate carpal tunnel syndrome, there is some electrophysiological evidence of traction on the adjacent ulnar nerve fibers. The findings do not indicate axonal degeneration of the ulnar nerve. PMID:25206437

Azmy, Radwa Mahmoud; Labib, Amira Ahmed; Elkholy, Saly Hassan

2013-05-25

328

Axonal degeneration of the ulnar nerve secondary to carpal tunnel syndrome: fact or fiction??  

PubMed Central

The distribution of sensory symptoms in carpal tunnel syndrome is strongly dependent on the degree of electrophysiological dysfunction of the median nerve. The association between carpal tunnel syndrome and ulnar nerve entrapment is still unclear. In this study, we measured ulnar nerve function in 82 patients with carpal tunnel syndrome. The patients were divided into group I with minimal carpal tunnel syndrome (n = 35) and group II with mild to moderate carpal tunnel syndrome (n = 47) according to electrophysiological data. Sixty-one age- and sex-matched subjects without carpal tunnel syndrome were used as a control group. There were no significant differences in ulnar sensory nerve peak latencies or conduction velocities from the 4th and 5th fingers between patients with carpal tunnel syndrome and the control group. The ulnar sensory nerve action potential amplitudes from the 4th and 5th fingers were lower in patients with carpal tunnel syndrome than in the control group. The ratios of the ulnar sensory nerve action potential amplitudes from the 4th and 5th fingers were almost the same in patients with carpal tunnel syndrome as in the control group. These findings indicate that in patients with minimal to moderate carpal tunnel syndrome, there is some electrophysiological evidence of traction on the adjacent ulnar nerve fibers. The findings do not indicate axonal degeneration of the ulnar nerve. PMID:25206437

Azmy, Radwa Mahmoud; Labib, Amira Ahmed; Elkholy, Saly Hassan

2013-01-01

329

Successful tactile based visual sensory substitution use functions independently of visual pathway integrity  

PubMed Central

Purpose: Neuronal reorganization after blindness is of critical interest because it has implications for the rational prescription of artificial vision devices. The purpose of this study was to distinguish the microstructural differences between perinatally blind (PB), acquired blind (AB), and normally sighted controls (SCs) and relate these differences to performance on functional tasks using a sensory substitution device (BrainPort). Methods: We enrolled 52 subjects (PB n = 11; AB n = 35; SC n = 6). All subjects spent 15 h undergoing BrainPort device training. Outcomes of light perception, motion, direction, temporal resolution, grating, and acuity were tested at baseline and after training. Twenty-six of the subjects were scanned with a three Tesla MRI scanner for diffusion tensor imaging (DTI), and with a positron emission tomography (PET) scanner for mapping regional brain glucose consumption during sensory substitution function. Non-parametric models were used to analyze fractional anisotropy (FA; a DTI measure of microstructural integrity) of the brain via region-of-interest (ROI) analysis and tract-based spatial statistics (TBSS). Results: At baseline, all subjects performed all tasks at chance level. After training, light perception, time resolution, location and grating acuity tasks improved significantly for all subject groups. ROI and TBSS analyses of FA maps show areas of statistically significant differences (p ? 0.025) in the bilateral optic radiations and some visual association connections between all three groups. No relationship was found between FA and functional performance with the BrainPort. Discussion: All subjects showed performance improvements using the BrainPort irrespective of nature and duration of blindness. Definite brain areas with significant microstructural integrity changes exist among PB, AB, and NC, and these variations are most pronounced in the visual pathways. However, the use of sensory substitution devices is feasible irrespective of microstructural integrity of the primary visual pathways between the eye and the brain. Therefore, tongue based devices devices may be usable for a broad array of non-sighted patients. PMID:24860473

Lee, Vincent K.; Nau, Amy C.; Laymon, Charles; Chan, Kevin C.; Rosario, Bedda L.; Fisher, Chris

2014-01-01

330

A Pilot Study Examining Activity Participation, Sensory Responsiveness, and Competence in Children with High Functioning Autism Spectrum Disorder  

Microsoft Academic Search

This pilot study explored activity patterns in children with and without ASD and examined the role of sensory responsiveness\\u000a in determining children’s level of competence in activity performance. Twenty-six children with high functioning ASD and twenty-six\\u000a typically-developing children 6–12 years old were assessed using the Sensory Profile and the Child Behavior Checklist. Results\\u000a reflect differences in the types of activities and

Stacey ReynoldsRoxanna; Roxanna M. Bendixen; Tami Lawrence

331

Doxycycline-regulated GDNF expression promotes axonal regeneration and functional recovery in transected peripheral nerve.  

PubMed

Increased production of neurotrophic factors (NTFs) is one of the key responses seen following peripheral nerve injury, making them an attractive choice for pro-regenerative gene therapies. However, the downside of over-expression of certain NTFs, including glial cell line-derived neurotrophic factor (GDNF), was earlier found to be the trapping and misdirection of regenerating axons, the so-called 'candy-store' effect. We report a proof-of-principle study on the application of conditional GDNF expression system in injured peripheral nerve. We engineered Schwann cells (SCs) using dendrimers or lentiviral transduction with the vector providing doxycycline-regulated GDNF expression. Injection of GDNF-modified cells into the injured peripheral nerve followed by time-restricted administration of doxycycline demonstrated that GDNF expression in SCs can also be controlled locally in the peripheral nerves of the experimental animals. Cell-based GDNF therapy was shown to increase the extent of axonal regeneration, while controlled deactivation of GDNF effectively prevented trapping of regenerating axons in GDNF-enriched areas, and was associated with improved functional recovery. PMID:24140746

Shakhbazau, Antos; Mohanty, Chandan; Shcharbin, Dzmitry; Bryszewska, Maria; Caminade, Anne-Marie; Majoral, Jean-Pierre; Alant, Jacob; Midha, Rajiv

2013-12-28

332

Double gene therapy with granulocyte colony-stimulating factor and vascular endothelial growth factor acts synergistically to improve nerve regeneration and functional outcome after sciatic nerve injury in mice.  

PubMed

Peripheral-nerve injuries are a common clinical problem and often result in long-term functional deficits. Reconstruction of peripheral-nerve defects is currently undertaken with nerve autografts. However, there is a limited availability of nerves that can be sacrificed and the functional recovery is never 100% satisfactory. We have previously shown that gene therapy with vascular endothelial growth factor (VEGF) significantly improved nerve regeneration, neuronal survival, and muscle activity. Our hypothesis is that granulocyte colony-stimulating factor (G-CSF) synergizes with VEGF to improve the functional outcome after sciatic nerve transection. The left sciatic nerves and the adjacent muscle groups of adult mice were exposed, and 50 or 100 ?g (in 50 ?l PBS) of VEGF and/or G-CSF genes was injected locally, just below the sciatic nerve, and transferred by electroporation. The sciatic nerves were transected and placed in an empty polycaprolactone (PCL) nerve guide, leaving a 3-mm gap to challenge nerve regeneration. After 6 weeks, the mice were perfused and the sciatic nerve, the dorsal root ganglion (DRG), the spinal cord and the gastrocnemius muscle were processed for light and transmission electron microscopy. Treated animals showed significant improvement in functional and histological analyses compared with the control group. However, the best results were obtained with the G-CSF+VEGF-treated animals: quantitative analysis of regenerated nerves showed a significant increase in the number of myelinated fibers and blood vessels, and the number of neurons in the DRG and motoneurons in the spinal cord was significantly higher. Motor function also showed that functional recovery occurred earlier in animals receiving G-CSF+VEGF-treatment. The gastrocnemius muscle showed an increase in weight and in the levels of creatine phosphokinase, suggesting an improvement of reinnervation and muscle activity. These results suggest that these two factors acted synergistically and optimized the nerve repair potential, improving regeneration after a transection lesion. PMID:23103791

Pereira Lopes, F R; Martin, P K M; Frattini, F; Biancalana, A; Almeida, F M; Tomaz, M A; Melo, P A; Borojevic, R; Han, S W; Martinez, A M B

2013-01-29

333

NEUROPHYSIOLOGICAL EVALUATION OF SENSORY SYSTEMS'  

EPA Science Inventory

Exposure to many neurotoxic compounds has been shown to produce a sensory system dysfunction. Neurophysiological assessment of sensory function in humans and animal models often uses techniques known as sensory evoked potentials. Because both humans and animals show analogous res...

334

Partial restoration of blink reflex function after spinal accessory-facial nerve anastomosis.  

PubMed Central

Functional motor control requires perfect matching of the central connections of motoneurons with their peripheral inputs. It is not known, however, to what extent these central circuits are influenced by target muscles, either during development or after a lesion. Surgical interventions aimed at restoring function after peripheral nerve lesions provide an opportunity for studying this interaction in the mature human nervous system. A patient was studied in whom the spinal accessory nerve was anastomosed into a lesioned facial nerve, allowing voluntary contractions of the previously paralysed muscles. This procedure, in addition to replacing the facial neurons at peripheral synapses, allowed a new short latency trigeminospinal accessory reflex of the R1 blink reflex type to be demonstrated, implying that trigeminal neurons had sprouted towards spinal accessory motoneurons over a distance of at least 1 cm. These results show an unexpected influence of the periphery in remodelling central connectivity in humans. The motoneuronal excitability for this R1 reflex response was therefore studied to compare the convergent properties of facial motoneurons (normal side) with those of the spinal accessory motoneurons (operated side) using a classic double shock technique with variable interstimulus intervals (conditioning test stimulus). On the normal side, conditioning stimuli (to the ipsilateral or contralateral infraliminar supraorbital nerve) produced a clearcut facilitation of the R1 blink reflex when the interstimulus interval was 30-80 ms. By contrast, a similar procedure had no effect on the R1 blink reflex mediated via the trigeminal-spinal accessory reflex arc. These data indicate that despite the heterotopic sprouting of some axons from neurons in the XIth nucleus, motoneurons involved in the newly formed reflex arc remain totally inexcitable by other trigeminal afferents and seem unable to ensure a physiological functioning of the normal blink reflex. Thus the functional relevance of the recovered R1 blink response remains unclear. PMID:7876856

Danziger, N; Chassande, B; Lamas, G; Fligny, I; Soudant, J; Willer, J C

1995-01-01

335

The anatomy and fine structure of the echidna Tachyglossus aculeatus snout with respect to its different trigeminal sensory receptors including the electroreceptors  

Microsoft Academic Search

The gross anatomy and nerve supply of the bill of echidna (Tachyglossus aculeatus) is described in relation to its function as an outstanding sensory organ. The sensory innervation of the skin of the echidna snout was investigated by means of frontal serial sections, after decalcification of the specimens. A comprehensive light and electron microscopic description of the location and fine

K. H. Andres; A. Iggo; U. Proske

1991-01-01

336

The Role of Cutaneous Innervation in the Sensory Abnormalities Associated with Diabetic Neuropathy  

E-print Network

Diabetes-induced nerve damage results in cutaneous denervation, nerve conduction slowing, suppressed regenerative responses, and debilitating painful or insensate sensory symptoms. The increasing prevalence of diabetic ...

Johnson, Megan Sarah

2008-05-05

337

A comparative morphological, electrophysiological and functional analysis of axon regeneration through peripheral nerve autografts genetically modified to overexpress BDNF, CNTF, GDNF, NGF, NT3 or VEGF.  

PubMed

The clinical outcome of microsurgical repair of an injured peripheral nerve with an autograft is suboptimal. A key question addressed here is: can axon regeneration through an autograft be further improved? In this article the impact of six neurotrophic factors (BDNF, CNTF, GDNF, NGF, NT3 or VEGF) on axon regeneration was compared after delivery to a 1cm long nerve autograft by gene therapy. To distinguish between early and late effects, regeneration was assessed at 2 and 20weeks post-surgery by histological, electrophysiological and functional analysis. BDNF, GDNF and NGF exhibited a spectrum of effects, including early stimulatory effects on axons entering the autograft and excessive axon growth and Schwann cell proliferation at 20weeks post-surgery. Persistent expression of these factors in autografts interfered with target cell reinnervation and functional recovery in a modality specific way. Autografts overexpressing VEGF displayed hypervascularization, while grafts transduced with CNTF and NT3 were indistinguishable from control grafts. These three factors did not have detectable pro-regenerative effects. In conclusion, autograft-based repair combined with gene therapy for three of the six growth factors investigated (BDNF, GDNF, NGF) showed considerable promise since these factors enhanced modality specific axon outgrowth in autografts. The remarkable and selective effects of BDNF, GDNF and NGF on motor or sensory regeneration will be exploited in future experiments that aim to carefully regulate their temporal and spatial expression since this has the potential to overcome the adverse effects on long-distance regeneration observed after uncontrolled delivery. PMID:25128265

Hoyng, Stefan A; De Winter, Fred; Gnavi, Sara; de Boer, Ralph; Boon, Lennard I; Korvers, Laura M; Tannemaat, Martijn R; Malessy, Martijn J A; Verhaagen, Joost

2014-11-01

338

Is the Sensory Organization Test a Reliable Measure of Central Sensory Function in Adults with Fibromyalgia? A common complaint among adults diagnosed with Fibromyalgia (FM) is postural instability and dizziness1  

E-print Network

interval separating the two tests.An Equilibrium Score (ES) was calculated for each of the three test the six testing conditions. Conducting a third assessment was suggested to increase the levelIs the Sensory Organization Test a Reliable Measure of Central Sensory Function in Adults

de Lijser, Peter

339

Dual functions of mammalian olfactory sensory neurons as odor detectors and mechanical sensors  

Microsoft Academic Search

Most sensory systems are primarily specialized to detect one sensory modality. Here we report that olfactory sensory neurons (OSNs) in the mammalian nose can detect two distinct modalities transmitted by chemical and mechanical stimuli. As revealed by patch-clamp recordings, many OSNs respond not only to odorants, but also to mechanical stimuli delivered by pressure ejections of odor-free Ringer solution. The

Xavier Grosmaitre; Lindsey C Santarelli; Jie Tan; Minmin Luo; Minghong Ma

2007-01-01

340

Microsurgical results with large vestibular schwannomas with preservation of facial and cochlear nerve function as the primary aim  

Microsoft Academic Search

Summary Objective. To evaluate our microsurgical results in dealing with vestibular schwannomas (VS) greater than or equal to 30?mm when preservation of cranial nerve function was considered more important than total tumour removal.

C. Raftopoulos; B. Abu Serieh; T. Duprez; M. A. Docquier; J. M. Guérit

2005-01-01

341

The effect of treatment with BRX-220, a co-inducer of heat shock proteins, on sensory fibers of the rat following peripheral nerve injury  

E-print Network

-regulated in small neurones (C fibers) and expressed ``de novo'' in large sensory neurones (Ah fibers; 0014The effect of treatment with BRX-220, a co-inducer of heat shock proteins, on sensory fibers the effect BRX-220, a co-inducer of heat shock proteins, in injury-induced peripheral neuropathy. Following

Burnstock, Geoffrey

342

Differences in risk factors for neurophysiologically confirmed carpal tunnel syndrome and illness with similar symptoms but normal median nerve function: a case–control study  

PubMed Central

Background To explore whether risk factors for neurophysiologically confirmed carpal tunnel syndrome (CTS) differ from those for sensory symptoms with normal median nerve conduction, and to test the validity and practical utility of a proposed definition for impaired median nerve conduction, we carried out a case–control study of patients referred for investigation of suspected CTS. Methods We compared 475 patients with neurophysiological abnormality (NP+ve) according to the definition, 409 patients investigated for CTS but classed as negative on neurophysiological testing (NP-ve), and 799 controls. Exposures to risk factors were ascertained by self-administered questionnaire. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated by logistic regression. Results NP+ve disease was associated with obesity, use of vibratory tools, repetitive movement of the wrist or fingers, poor mental health and workplace psychosocial stressors. NP-ve illness was also related to poor mental health and occupational psychosocial stressors, but differed from NP+ve disease in showing associations also with prolonged use of computer keyboards and tendency to somatise, and no relation to obesity. In direct comparison of NP+ve and NP-ve patients (the latter being taken as the reference category), the most notable differences were for obesity (OR 2.7, 95 % CI 1.9-3.9), somatising tendency (OR 0.6, 95% CI 0.4-0.9), diabetes (OR 1.6, 95% CI 0.9-3.1) and work with vibratory tools (OR 1.4, 95% CI 0.9-2.2). Conclusions When viewed in the context of earlier research, our findings suggest that obesity, diabetes, use of hand-held vibratory tools, and repeated forceful movements of the wrist and hand are causes of impaired median nerve function. In addition, sensory symptoms in the hand, whether from identifiable pathology or non-specific in origin, may be rendered more prominent and distressing by hand activity, low mood, tendency to somatise, and psychosocial stressors at work. These differences in associations with risk factors support the validity of our definition of impaired median nerve conduction. PMID:23947720

2013-01-01

343

[Axon-reflex based nerve fiber function assessment in the detection of autonomic neuropathy].  

PubMed

Axon-reflex-based tests of peripheral small nerve fiber function including techniques to quantify vasomotor and sudomotor responses following acetylcholine iontophoresis are used in the assessment of autonomic neuropathy. However, the established axon-reflex-based techniques, laser Doppler flowmetry (LDF) to assess vasomotor function and quantitative sudomotor axon-reflex test (QSART) to measure sudomotor function, are limited by technically demanding settings as well as interindividual variability and are therefore restricted to specialized clinical centers. New axon-reflex tests are characterized by quantification of axon responses with both temporal and spatial resolution and include "laser Doppler imaging (LDI) axon-reflex flare area test" to assess vasomotor function, the quantitative direct and indirect test of sudomotor function (QDIRT) to quantify sudomotor function, as well as the quantitative pilomotor axon-reflex test (QPART), a technique to measure pilomotor nerve fiber function using adrenergic cutaneous stimulation through phenylephrine iontophoresis. The effectiveness of new axon-reflex tests in the assessment of neuropathy is currently being investigated in clinical studies. PMID:25047406

Siepmann, T; Illigens, B M-W; Reichmann, H; Ziemssen, T

2014-10-01

344

Task-related training combined with transcutaneous electrical nerve stimulation promotes upper limb functions in patients with chronic stroke.  

PubMed

Severe upper limb paresis is a major contributor to disability after stroke. This study investigated the efficacy of task-related training (TRT) with transcutaneous electrical nerve stimulation (TENS) on recovery of upper limb motor function in chronic-stroke survivors. Thirty patients with chronic stroke were randomly allocated two groups: the TRT+TENS group (n = 15) and the TRT+placebo (TRT+PLBO) group (n = 15). Patients in the TRT+TENS group received TENS stimulation (two to three times the sensory threshold), while subjects in the TRT+PLBO group received TENS without real electrical stimulation. TENS was applied to muscle belly of triceps and wrist extensors, while placebo (PLBO) stimulation was administrated without real electrical stimulation. Both interventions were given for 30 minutes per day, 5 days per week, for a period of 4 weeks. The primary outcomes were assessed with Fugl-Meyer assessment scores (FMA), Manual function test (MFT), Box and block test (BBT), and Modified Ashworth scale (MAS), each of which was performed one day before and one day after intervention. Both groups showed significant improvements in FMA, MFT, and BBT after intervention. When compared with the TRT+PLBO group, the TRT+TENS group showed significantly greater improvements in FMA (p = 0.034), MFT (p = 0.037), and BBT (p = 0.042). In MAS score, significant improvement was observed only in the TRT+TENS group (p = 0.011). Our findings indicate that TRT with TENS can reduce motor impairment and improve motor activity in stroke survivors with chronic upper limb paresis, highlighting the benefits of somatosensory stimulation from TENS. PMID:24097280

Kim, Tae Hoon; In, Tae Sung; Cho, Hwi-young

2013-01-01

345

Effect of in situ delivery of acetyl-L-carnitine on peripheral nerve regeneration and functional recovery in transected sciatic nerve in rat.  

PubMed

The repair of peripheral nerve injuries is still one of the most challenging tasks and concerns in neurosurgery, plastic and orthopedic surgery. Effect of acetyl-L-carnitine (ALC) loaded chitosan conduit as an in situ delivery system of ALC in bridging the defects was studied using a rat sciatic nerve regeneration model. A 10-mm sciatic nerve defect was bridged using a chitosan conduit (CHIT/ALC) filled with 10 ?L ALC (100 ng/mL). In control group (CHIT), the conduit was filled with the same volume of the phosphate buffered solution. The regenerated fibers were studied 4, 8, 12 and 16 weeks after surgery. The functional and electrophysiological studies confirmed faster recovery of the regenerated axons in ALC treated than control group (P < 0.05). The mean ratios of gastrocnemius muscles weight were measured. There was statistically significant difference between the muscle weight ratios of CHIT/ALC and CHIT groups (P<0.05). Morphometric indices of regenerated fibers showed number and diameter of the myelinated fibers in CHIT/ALC were significantly higher than in control group. In immuohistochemistry, the location of reactions to S-100 in CHIT/ALC was clearly more positive than CHIT group. ALC when loaded in a chitosan conduit resulted in improvement of functional recovery and quantitative morphometric indices of sciatic nerve. PMID:25448663

Farahpour, Mohammad Reza; Ghayour, Sina Jangkhahe

2014-12-01

346

Rescue of cortical neurovascular functions during the hyperacute phase of ischemia by peripheral sensory stimulation.  

PubMed

To investigate the potential therapeutic effects of peripheral sensory stimulation during the hyperacute phase of stroke, the present study utilized electrophysiology and photoacoustic imaging techniques to evaluate neural and vascular responses of the rat cortex following ischemic insult. We employed a rat model of photothrombotic ischemia (PTI), which targeted the forelimb region of the primary somatosensory cortex (S1FL), due to its high reproducibility in creating localized ischemic injury. We also established a hybrid, dual-modality system, including six-channel electrocorticography (ECoG) and functional photoacoustic microscopy (fPAM), termed ECoG-fPAM, to image brain functional responses to peripheral sensory stimulation during the hyperacute phase of PTI. Our results showed that the evoked cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) recovered to 84±7.4% and 79±6.2% of the baseline, respectively, when stimulation was delivered within 2.5h following PTI induction. Moreover, neural activity significantly recovered, with 77±8.6%, 76±5.3% and 89±8.2% recovery for the resting-state inter-hemispheric coherence, alpha-to-delta ratio (ADR) and somatosensory evoked potential (SSEP), respectively. Additionally, we integrated the CBV or SO2 with ADR values as a recovery indicator (RI) to assess functional recovery after PTI. The RI indicated that 80±4.2% of neurovascular function was preserved when stimulation was delivered within 2.5h. Additionally, stimulation treatment within this optimal time window resulted in a minimal infarct volume in the ischemic hemisphere (4.6±2.1%). In contrast, the infarct volume comprised 13.7±1.7% of the ischemic hemisphere when no stimulation treatment was applied. PMID:25573087

Liao, Lun-De; Liu, Yu-Hang; Lai, Hsin-Yi; Bandla, Aishwarya; Shih, Yen-Yu Ian; Chen, You-Yin; Thakor, Nitish V

2015-03-01

347

Nerve Regeneration Restores Supraspinal Control of Bladder Function after Complete Spinal Cord Injury  

PubMed Central

A life-threatening disability after complete spinal cord injury is urinary dysfunction, which is attributable to lack of regeneration of supraspinal pathways that control the bladder. Although numerous strategies have been proposed that can promote the regrowth of severed axons in the adult CNS, at present, the approaches by which this can be accomplished after complete cord transection are quite limited. In the present study, we modified a classic peripheral nerve grafting technique with the use of chondroitinase to facilitate the regeneration of axons across and beyond an extensive thoracic spinal cord transection lesion in adult rats. The novel combination treatment allows for remarkably lengthy regeneration of certain subtypes of brainstem and propriospinal axons across the injury site and is followed by markedly improved urinary function. Our studies provide evidence that an enhanced nerve grafting strategy represents a potential regenerative treatment after severe spinal cord injury. PMID:23804083

Lin, Ching-Yi; Jiang, Hai-Hong; DePaul, Marc; Lin, Vernon W.

2013-01-01

348

Influence of putrescine and carnauba wax on functional and sensory quality of pomegranate (Punica granatum L.) fruits during storage.  

PubMed

Functional properties (anthocyanins, antioxidant, ascorbic acid and tannin) and sensory score were determined in pomegranate fruits at two storage temperatures (3 and 5 °C) after treatment with 2 mM putrescine and 1 : 10 carnauba wax (carnauba wax : water). The treatments (putrescine and carnauba wax) were given by immersion method followed by storage up to 60 days. Both treatments retained significantly higher anthocyanins, antioxidant, ascorbic acid, tannin and sensory qualities as compared with control fruits under both the storage conditions. Combined application of putrescine + carnauba wax showed better response in retaining functional properties than putrescine treated or nontreated fruits. The impacts of putrescine and carnauba wax treatments were found more pronounced after 30 days at 3-5 °C storage temperature in retaining functional and sensory qualities. After 60 days of storage, putrescine + carnauba wax retained about 25% higher antioxidant activity both at 3 and 5 °C storage temperatures. PMID:24426055

Barman, Kalyan; Asrey, Ram; Pal, R K; Kaur, Charanjit; Jha, S K

2014-01-01

349

Intramuscular nerve distribution in bladder and the relationship between intramuscular ganglia and bladder function in man and dog  

PubMed Central

In clinical, the relationship between bladder intramuscular nerve and function is also elusive. This study aims to compare the bladder intramuscular nerve distribution and its characteristics and significance in human and dog. Eleven dogs’ bladders were stained by Sihler’s and HE techniques. Fifteen human bladders were adopted by Sihler’s staining, using 10% formaldehyde to fix 12 weeks, 7 by HE dyeing fixes 24 hours. Results indicated that man’s bladder was triangularpyramid-shaped. While dog’s bladder was spherical-shaped and its muscle fibers arrange were irregularly shaped. Longitudinal muscle of the outer layer is fleshy, the terminal is at the bladder neck without exception, and vesical trigone has relatively obvious three layers of structure. After dyeing dog’s bladder was transparent jelly, the nerve was purple color, enter bladder at the ureter-bladder junction with different forms. Man’s bladder nerves, no ganglion, were more trivial than that of dogs, and with smaller branches, the large nerve ganglion. The links with the nerve fibers and forms the network on the dog’s bladder wall, and the nerve fibers crosses comparatively little on both the left and right sides in the midline. The right nerve branch gains advantage on the man’s bladder wall, the situations is opposite on the dog’s. In conclusion, bladder nerves which scatter to the bladder wall have branches to lower ureter at the ureter-bladder junction, the structure and distribution of intramuscular nerves are different, the existence of intramuscular ganglia is relating to the bladder function both in man and dog. PMID:25664008

Zhao, Zeju; Xu, Qian; Lu, Li; Luo, Xu; Fu, Xiaoyun

2014-01-01

350

Early specification of sensory neuron fate revealed by expression and function of neurogenins in the chick embryo.  

PubMed

The generation of sensory and autonomic neurons from the neural crest requires the functions of two classes of basic helix-loop-helix (bHLH) transcription factors, the Neurogenins (NGNs) and MASH-1, respectively (Fode, C., Gradwohl, G., Morin, X., Dierich, A., LeMeur, M., Goridis, C. and Guillemot, F. (1998) Neuron 20, 483-494; Guillemot, F., Lo, L.-C., Johnson, J. E., Auerbach, A., Anderson, D. J. and Joyner, A. L. (1993) Cell 75, 463-476; Ma, Q., Chen, Z. F., Barrantes, I. B., de la Pompa, J. L. and Anderson, D. J. (1998 Neuron 20, 469-482). We have cloned two chick NGNs and found that they are expressed in a subset of neural crest cells early in their migration. Ectopic expression of the NGNs in vivo biases migrating neural crest cells to localize in the sensory ganglia, and induces the expression of sensory neuron-appropriate markers in non-sensory crest derivatives. Surprisingly, the NGNs can also induce the expression of multiple pan-neuronal and sensory-specific markers in the dermomyotome, a mesodermal derivative. Taken together, these data suggest that a subset of neural crest cells may already be specified for a sensory neuron fate early in migration, as a consequence of NGN expression. PMID:10079233

Perez, S E; Rebelo, S; Anderson, D J

1999-04-01

351

Drosophila Notch Receptor Activity Suppresses Hairless Function during Adult External Sensory Organ Development  

PubMed Central

The neurogenic Notch locus of Drosophila encodes a receptor necessary for cell fate decisions within equivalence groups, such as proneural clusters. Specification of alternate fates within clusters results from inhibitory communication among cells having comparable neural fate potential. Genetically, Hairless (H) acts as an antagonist of most neurogenic genes and may insulate neural precursor cells from inhibition. H function is required for commitment to the bristle sensory organ precursor (SOP) cell fate and for daughter cell fates. Using Notch gain-of-function alleles and conditional expression of an activated Notch transgene, we show that enhanced signaling produces H-like loss-of-function phenotypes by suppressing bristle SOP cell specification or by causing an H-like transformation of sensillum daughter cell fates. Furthermore, adults carrying Notch gain of function and H alleles exhibit synergistic enhancement of mutant phenotypes. Over-expression of an H(+) transgene product suppressed virtually all phenotypes generated by Notch gain-of-function genotypes. Phenotypes resulting from over-expression of the H(+) transgene were blocked by the Notch gain-of-function products, indicating a balance between Notch and H activity. The results suggest that H insulates SOP cells from inhibition and indicate that H activity is suppressed by Notch signaling. PMID:8601489

Lyman, D. F.; Yedvobnick, B.

1995-01-01

352

Effect of lycium barbarum (wolfberry) polysaccharides on preserving retinal function after partial optic nerve transection.  

PubMed

Lycium Barbarum Polysaccharides (LBP) are the active components of Wolfberry (a traditional Chinese medicine) which has long been used for improving visual function. This study aims to investigate localized changes of retinal function in a partial optic nerve transection (PONT) model, and effects of LBP on visual function. The multifocal electroretinograms (mfERG) were obtained from 30 eyes of 30 Sprague-Dawley rats. The rats were divided into 6 groups (five treatment groups and one control group). Starting from the first day of the experiment, the rats in the (PONT+LBP) group and the (LBP) group were dosed with LBP; rats in the (PONT+PBS (phosphate buffered saline)) group and the (PBS) group were dosed with PBS via nasogastric tube every day until euthanized. The dorsal part of the optic nerve was transected in the (PONT), (PONT+LBP) and (PONT+PBS) groups at the end of week 1 (day 7 after LBP or PBS feeding began). The mfERG was measured at three time points: week 2, week 3 and week 5. Significant reduction of P1 and PhNR amplitudes of the mfERG were observed in all retinal regions a week after PONT. Feeding with LBP prior to PONT preserved retinal function. All mfERG responses returned to the normal range in the superior retina, which corresponds to the transected dorsal region of the optic nerve, while most of the inferior retinal responses were significantly increased at week 4 after PONT. The ventral part of the retina had secondary degeneration which was not only limited to the ganglion cell layer, but is a widespread effect affecting the outer retina. LBP altered the functional reduction caused by PONT by regulating the signal from the outer retina. PMID:24339917

Chu, Patrick H W; Li, Hong-Ying; Chin, Man-Pan; So, Kwok-fai; Chan, Henry H L

2013-01-01

353

Neuropathic pain: is quantitative sensory testing helpful?  

PubMed

Neuropathic pain arises as a consequence of a lesion or disease affecting the somatosensory system and is characterised by a combination of positive and negative sensory symptoms. Quantitative sensory testing (QST) examines the sensory perception after application of different mechanical and thermal stimuli of controlled intensity and the function of both large (A-beta) and small (A-delta and C) nerve fibres, including the corresponding central pathways. QST can be used to determine detection, pain thresholds and stimulus-response curves and can thus detect both negative and positive sensory signs, the second ones not being assessed by other methods. Similarly to all other psychophysical tests QST requires standardised examination, instructions and data evaluation to receive valid and reliable results. Since normative data are available, QST can contribute also to the individual diagnosis of neuropathy, especially in the case of isolated small-fibre neuropathy, in contrast to the conventional electrophysiology which assesses only large myelinated fibres. For example, detection of early stages of subclinical neuropathy in symptomatic or asymptomatic patients with diabetes mellitus can be helpful to optimise treatment and identify diabetic foot at risk of ulceration. QST assessed the individual's sensory profile and thus can be valuable to evaluate the underlying pain mechanisms which occur in different frequencies even in the same neuropathic pain syndromes. Furthermore, assessing the exact sensory phenotype by QST might be useful in the future to identify responders to certain treatments in accordance to the underlying pain mechanisms. PMID:22623149

Krumova, Elena K; Geber, Christian; Westermann, Andrea; Maier, Christoph

2012-08-01

354

Electrophysiological and Functional Effects of Shock Waves on the Sciatic Nerve of Rats  

Microsoft Academic Search

Extracorporeal shockwave therapy (ESWT) has been applied in lithotripsy and treatments of musculoskeletal disorders over the past decade, but its effects on peripheral nerves remain unclear. This study investigated the short-term effects of shockwaves on the sciatic nerve of rats. The nerves were surgically exposed and then stimulated with shockwaves at three intensities. We evaluated the motor nerve conduction velocity

Yi-Hui Wu; Huey-Wen Liang; Wen-Shiang Chen; Jin-Shin Lai; Jer-Junn Luh; Fok-Ching Chong

2008-01-01

355

Functional outcome of anterior transposition of the vascularized ulnar nerve for cubital tunnel syndrome  

Microsoft Academic Search

Anterior transposition of the ulnar nerve is a widely used treatment for cubital tunnel syndrome, but neurolysis performed at the time of surgery may impair the blood supply to the ulnar nerve. This study compared the results of intramuscular anterior transposition of the ulnar nerve with or without preserving the extrinsic vessels of the ulnar nerve in 35 patients. The

A. Asami; K. Morisawa; T. Tsuruta

1998-01-01

356

Functional Regeneration of Recurrent Laryngeal Nerve Injury During Thyroid Surgery Using an Asymmetrically Porous Nerve Guide Conduit in an Animal Model  

PubMed Central

Background: Vocal cord paralysis (VCP) caused by recurrent laryngeal nerve (RLN) damage during thyroidectomy commonly results in serious medico-legal problems. The purpose of this study was to evaluate the usefulness of an asymmetrically porous polycaprolactone (PCL)/Pluronic F127 nerve guide conduit (NGC) for functional regeneration in a RLN injury animal model. Methods: A biodegradable, asymmetrically porous PCL/F127 NGC with selective permeability was fabricated for use in this study. A 10-mm segment of left RLN was resected in 28 New Zealand white rabbits, and then an asymmetrically porous NGC or a nonporous silicone tube was interposed between both stumps and securely fixed. Vocal cord mobility was endoscopically evaluated at one, four, and eight weeks postoperatively. Nerve growth through NGCs was assessed by toluidine blue staining, and thyroarytenoid (TA) muscle atrophy was evaluated by hematoxylin and eosin staining. Immunohistochemical stainings for acetylcholinesterase (AchE), anti-neurofilament (NF), and anti-S100 protein were also conducted, and transmission electron microscopy (TEM) was used to evaluate functional nerve regeneration. Results: At eight weeks postoperatively, endoscopic evaluations showed significantly better recovery from VCP in the asymmetrically porous PCL/F127 NGC group (6 of 10 rabbits) than in the silicone tube group (1 of 10 rabbits). Continued nerve growth on the damaged nerve endings was observed with time in the asymmetrically porous PCL/F127 NGC-interposed RLNs. TA muscle dimensions and AchE expressions in TA muscle were significantly greater in the asymmetrically porous PCL/F127 NGC group than in the silicone tube group. Furthermore, immunohistochemical staining revealed the expression of NF and S100 protein in the regenerated nerves in the asymmetrically porous PCL/F127 NGC group at eight weeks postoperatively, and at this time, TEM imaging showed myelinated axons in the regenerated RLNs. Conclusion: The study shows that asymmetrically porous PCL/F127 NGC provides a favorable environment for RLN regeneration and that it has therapeutic potential for the regeneration of RLN damage. PMID:24015805

Choi, Jeong-Seok; Oh, Se Heang; An, Hye-Young; Kim, Young-Mo; Lee, Jin Ho

2014-01-01

357

Biophysical and functional consequences of receptor-mediated nerve fiber transformation.  

PubMed Central

Stimulation of the nervous system by substance P, a G protein-coupled receptor, and subsequent receptor internalization causes dendrites to change their shape from homogeneous cylinders to a heterogeneous string of swollen varicosities (beads) connected by thin segments. In this paper we have analyzed this phenomenon and propose quantitative mechanisms to explain this type of physical shape transformation. We developed a mathematical solution to describe the relationship between the initial radius of a cylindrical nerve fiber and the average radii of the subsequently created varicosities and connecting segments, as well as the periodicity of the varicosities along the nerve fiber. Theoretical predictions are in good agreement with our own and published experimental data from dorsal root ganglion neurons, spinal cord, and brain. Modeling the electrical properties of these beaded fibers has led to an understanding of the functional biophysical consequences of nerve fiber transformation. Several hypotheses for how this shape transformation can be used to process information within the nervous system have been put forth. Images FIGURE 1 FIGURE 6 PMID:9138558

Tanelian, D L; Markin, V S

1997-01-01

358

Transfer function analysis from arterial baroreceptor afferent activity to renal nerve activity in rabbits.  

PubMed

In vagotomized and anesthetized rabbits, aortic pressure (AP), aortic depressor nerve activity (ANA), and renal sympathetic nerve activity (RNA) were simultaneously measured while perturbing AP randomly. To quantitatively characterize the role of the arterial baroreflex system in generating RNA, we determined the transfer function (TF) of the central baroreflex arc from ANA to RNA in the frequency domain (0.02-5 Hz). The magnitude of squared coherence was > 0.5, the phase was close to -180 degrees, and the gain of TF was flat over 0.02-0.3 Hz, indicating that changes in RNA were linearly and instantaneously but inversely related to changes in ANA over this frequency range. Above 0.3 Hz, the coherence was low, suggesting that RNA unrelated to ANA existed in the frequency range. In animals without AP perturbations, power spectrum of RNA resided over 0.2-5 Hz with a broad peak at 1 Hz, which may represent central activity. Our results suggest that over 0.02-0.3 Hz the relationship between arterial baroreceptor afferent nerve activity and RNA is linear and instantaneous but above 0.3 Hz it is not linear possibly due to an interaction between central activity and arterial baroreflex. PMID:8304519

Imaizumi, T; Harasawa, Y; Ando, S; Sugimachi, M; Takeshita, A

1994-01-01

359

SMN is required for sensory-motor circuit function in Drosophila  

PubMed Central

Summary Spinal muscular atrophy (SMA) is a lethal human disease characterized by motor neuron dysfunction and muscle deterioration due to depletion of the ubiquitous Survival Motor Neuron (SMN) protein. Drosophila SMN mutants have reduced muscle size and defective locomotion, motor rhythm and motor neuron neurotransmission. Unexpectedly, restoration of SMN in either muscles or motor neurons did not alter these phenotypes. Instead, SMN must be expressed in proprioceptive neurons and interneurons in the motor circuit to non-autonomously correct defects in motor neurons and muscles. SMN depletion disrupts the motor system subsequent to circuit development and can be mimicked by the inhibition of motor network function. Furthermore, increasing motor circuit excitability by genetic or pharmacological inhibition of K+ channels can correct SMN-dependent phenotypes. These results establish sensory-motor circuit dysfunction as the origin of motor system deficits in this SMA model and suggest that enhancement of motor neural network activity could ameliorate the disease. PMID:23063130

Imlach, Wendy L.; Beck, Erin S.; Choi, Ben Jiwon; Lotti, Francesco; Pellizzoni, Livio; McCabe, Brian D.

2012-01-01

360

Neuroprotectin D1 Restores Corneal Nerve Integrity and Function After Damage From Experimental Surgery  

PubMed Central

Purpose. To investigate if topical treatment of neuroprotectin D1 (NPD1) increases regeneration of functional nerves after lamellar keratectomy. Methods. An 8-mm stromal dissection was performed in the left eye of each rabbit. The rabbits were treated with NPD1, pigment epithelial-derived factor (PEDF) in combination with docosahexaenoic acid (DHA) or vehicle for 6 weeks, and corneas were obtained at 8 weeks. After fixation, corneal wholemounts were stained with mouse monoclonal anti-?III-tubulin antibody and double stained with chicken anti-calcitonin gene-related peptide (CGRP) antibody. Corneal sensitivity and tear secretion were measured using the Cochet-Bonnet esthesiometer and the Schirmer's test, respectively. Additional rabbits were treated with NPD1, PEDF+DHA, or vehicle, and corneal sections were stained with a rat monoclonal anti-neutrophil antibody. Cultures of trigeminal ganglia from 5-day-old mice were treated with NPD1, PEDF+DHA, lipoxin A4 (LXA4), 12- or 15-hydroxyeicosatetraenoic acid (12[S] or 15[S]-HETE), and nerve growth factor (NGF) as positive control. Results. NPD1 increased subepithelial corneal nerve area three times compared with vehicle-treated rabbits. The effect was similar to PEDF+DHA–treated animals. There was recovery of CGRP-positive neurons and an increase in corneal sensitivity and tear secretion in NPD1-treated animals. NPD1 decreased neutrophil infiltration after 2 and 4 days of treatment. In the in vitro cultures, NPD1 and PEDF+DHA induced a 3-fold increase in neurite outgrowth compared with cultures without supplementation. Treatments with LXA4, 12(S)-, and 15(S)- HETE did not stimulate neurite outgrowth. Conclusions. NPD1 has anti-inflammatory and nerve regenerative properties. This study demonstrates that NPD1 may offer an effective treatment for neurotrophic corneas. PMID:23702780

Cortina, Maria Soledad; He, Jiucheng; Russ, Tiffany; Bazan, Nicolas G.; Bazan, Haydee E. P.

2013-01-01

361

The spinal accessory nerve plexus, the trapezius muscle, and shoulder stabilization after radical neck cancer surgery.  

PubMed Central

A clinical and anatomic study of the spinal accessory, the eleventh cranial nerve, and trapezius muscle function of patients who had radical neck cancer surgery was conducted. This study was done not only to document the indispensibility of the trapezius muscle to shoulder-girdle stability, but also to clarify the role of the eleventh cranial nerve in the variable motor and sensory changes occurring after the loss of this muscle. Seventeen male patients, 49-69 years of age, (average of 60 years of age) undergoing a total of 23 radical neck dissections were examined for upper extremity function, particularly in regard to the trapezius muscle, and for subjective signs of pain. The eleventh nerve, usually regarded as the sole motor innervation to the trapezius, was cut in 17 instances because of tumor involvement. Dissection of four fresh and 30 preserved adult cadavers helped to reconcile the motor and sensory differences in patients who had undergone loss of the eleventh nerve. The dissections and clinical observations corroborate that the trapezius is a key part of a "muscle continuum" that stabilizes the shoulder. Variations in origins and insertions of the trapezius may influence its function in different individuals. As regards the spinal accessory nerve, it is concluded that varying motor and sensory connections form a plexus with the eleventh nerve, accounting, in part, for the variations in motor innervation and function of the trapezius, as well as for a variable spectrum of sensory changes when the eleventh nerve is cut. For this reason, it is suggested that the term "spinal accessory nerve plexus" be used to refer to the eleventh nerve when it is considered in the context of radical neck cancer surgery. Images Fig. 4. Fig. 6. Fig. 7. Fig. 8. PMID:3056289

Brown, H; Burns, S; Kaiser, C W

1988-01-01

362

Accelerating axonal growth promotes motor recovery after peripheral nerve injury in mice  

PubMed Central

Although peripheral nerves can regenerate after injury, proximal nerve injury in humans results in minimal restoration of motor function. One possible explanation for this is that injury-induced axonal growth is too slow. Heat shock protein 27 (Hsp27) is a regeneration-associated protein that accelerates axonal growth in vitro. Here, we have shown that it can also do this in mice after peripheral nerve injury. While rapid motor and sensory recovery occurred in mice after a sciatic nerve crush injury, there was little return of motor function after sciatic nerve transection, because of the delay in motor axons reaching their target. This was not due to a failure of axonal growth, because injured motor axons eventually fully re-extended into muscles and sensory function returned; rather, it resulted from a lack of motor end plate reinnervation. Tg mice expressing high levels of Hsp27 demonstrated enhanced restoration of motor function after nerve transection/resuture by enabling motor synapse reinnervation, but only within 5 weeks of injury. In humans with peripheral nerve injuries, shorter wait times to decompression surgery led to improved functional recovery, and, while a return of sensation occurred in all patients, motor recovery was limited. Thus, absence of motor recovery after nerve damage may result from a failure of synapse reformation after prolonged denervation rather than a failure of axonal growth. PMID:21965333

Ma, Chi Him Eddie; Omura, Takao; Cobos, Enrique J.; Latrémoličre, Alban; Ghasemlou, Nader; Brenner, Gary J.; van Veen, Ed; Barrett, Lee; Sawada, Tomokazu; Gao, Fuying; Coppola, Giovanni; Gertler, Frank; Costigan, Michael; Geschwind, Dan; Woolf, Clifford J.

2011-01-01

363

Thirty minutes of low intensity electrical stimulation promotes nerve regeneration after sciatic nerve crush injury in a rat model.  

PubMed

We investigated whether electrical stimulation (ES) applied directly for 30 minutes after crushing injury to the sciatic nerves of rats could improve nerve regeneration. Two groups of animals were used in this study (n = 20 each): the ES group received 30 minutes of low intensity ES (20 Hz pulse rate, 2 uA amplitude) immediately after a standard crush injury, while the control group received no stimulation after injury. Both groups were followed up for three weeks. The sciatic function index (SFI) was calculated weekly. Mean conduction velocity (MCV) and peak voltage (PV) were calculated, and the sensory neurons in L4 and L5 dorsal root ganglia (DRG) were traced with Fluorogold in retrograde fashion and quantified at the end of the follow up period. Histomorphometric studies were also carried out in both groups. The ES group showed improved functional and sensory recovery compared to the control group three weeks after injury. SFI, MCV and the number of retrogradely labeled sensory neurons were significantly higher in the ES group. Additionally, axon counts, myelin thicknesses and G-ratio values were also higher in the ES group. Quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) showed an elevated expression of brain derived neurotrophic factor (BDNF) in DRG sensory neurons of the ES group five days post-injury. Here, we present the first evidence that the application of ES for 30 minutes immediately following crush injury is effective to promote nerve regeneration in a rat sciatic nerve model. PMID:20873447

Alrashdan, Mohammad S; Park, Jong-Chul; Sung, Mi-Ae; Yoo, Sang Bae; Jahng, Jeong Won; Lee, Tae Hyung; Kim, Sung-June; Lee, Jong-Ho

2010-06-01

364

DECREASED SENSORY RECEPTORS P2X 3 AND TRPV1 IN SUBUROTHELIAL NERVE FIBERS FOLLOWING INTRADETRUSOR INJECTIONS OF BOTULINUM TOXIN FOR HUMAN DETRUSOR OVERACTIVITY  

Microsoft Academic Search

PurposeBotulinum neurotoxin type A (BoNT\\/A) is effective in the treatment of intractable detrusor overactivity (DO). In addition to its known inhibitory effect on presynaptic release of acetylcholine by motor terminals, there is increasing evidence that BoNT\\/A may affect sensory fibers. We investigated a possible effect of BoNT\\/A on human bladder afferent mechanisms by studying the sensory receptors P2X3 and TRPV1

A. APOSTOLIDIS; R. POPAT; Y. YIANGOU; D. COCKAYNE; A. P. D. W. FORD; J. B. DAVIS; P. DASGUPTA; C. J. FOWLER; P. ANAND

2005-01-01

365

Differential effects of distal and proximal nerve lesions on carbonic anhydrase activity in rat primary sensory neurons, ventral and dorsal root axons  

Microsoft Academic Search

The effect of proximal and distal peripheral nerve injuries on the histochemistry of carbonic anhydrase (CA) in rat dorsal root ganglion (DRG) neurons, and myelinated (MyF) dorsal and ventral root fibers was studied. Sciatic neurectomy induced no change. Contrariwise, 7 days after lumbar spinal nerve section the numbers of CA-stained ventral root MyF and DRG cells at the L4 and

J. M. Peyronnard; L. F. Charron; J. P. Messier; J. Lavoie

1988-01-01

366

A comparative study evoking a sensory action potential from the medial and lateral plantar nerves using the probe and ring method of stimulation.  

PubMed

Nerve conduction studies (NCS) aid in the detection of foot nerve pathologies. However, there has been a debate on method of plantar nerves stimulation that is more effective; the ring method of stimulation or probe method of stimulation. This study aims at determining the one method that is more effective among the two methods of stimulating for eliciting proper responses. Thirty healthy adults, aged 19 to 55 years, free of any neurological disease were the subjects of the study. Values considered for determining the effectiveness of the stimulating technique were mean amplitudes of the evoked responses from medial and lateral plantar nerves. A significant increase in amplitude difference was noted in favor of the probe stimulation method. The amplitude difference noted in favor of the probe method of stimulation was double the values elicited by the ring method of stimulation in both the medial and lateral plantar nerves. Results suggest that the direct probe method of stimulation may be a more effective method of stimulating for the medial and lateral plantar nerves studies. PMID:20508349

Adam, Jamila K; Bechoo, Reneal; Rmaih, Wafaa S

2010-01-01

367

Conserved Dopamine Neurotrophic Factor-Transduced Mesenchymal Stem Cells Promote Axon Regeneration and Functional Recovery of Injured Sciatic Nerve  

PubMed Central

Peripheral nerve injury (PNI) is a common disease that often results in axonal degeneration and the loss of neurons, ultimately leading to limited nerve regeneration and severe functional impairment. Currently, there are no effective treatments for PNI. In the present study, we transduced conserved dopamine neurotrophic factor (CDNF) into mesenchymal stem cells (MSCs) in collagen tubes to investigate their regenerative effects on rat peripheral nerves in an in vivo transection model. Scanning electron microscopy of the collagen tubes demonstrated their ability to be resorbed in vivo. We observed notable overexpression of the CDNF protein in the distal sciatic nerve after application of CDNF-MSCs. Quantitative analysis of neurofilament 200 (NF200) and S100 immunohistochemistry showed significant enhancement of axonal and Schwann cell regeneration in the group receiving CDNF-MSCs (CDNF-MSCs group) compared with the control groups. Myelination thickness, axon diameter and the axon-to fiber diameter ratio (G-ratio) were significantly higher in the CDNF-MSCs group at 8 and 12 weeks after nerve transection surgery. After surgery, the sciatic functional index, target muscle weight, wet weight ratio of gastrocnemius muscle and horseradish peroxidase (HRP) tracing demonstrated functional recovery. Light and electron microscopy confirmed successful regeneration of the sciatic nerve. The greater numbers of HRP-labeled neuron cell bodies and increased sciatic nerve index values (SFI) in the CDNF-MSCs group suggest that CDNF exerts neuroprotective effects in vivo. We also observed higher target muscle weights and a significant improvement in muscle atrophism in the CDNF-MSCs group. Collectively, these findings indicate that CDNF gene therapy delivered by MSCs is capable of promoting nerve regeneration and functional recovery, likely because of the significant neuroprotective and neurotrophic effects of CDNF and the superior environment offered by MSCs and collagen tubes. PMID:25343619

Liu, Yi; Nie, Lin; Zhao, Hua; Zhang, Wen; Zhang, Yuan-Qiang; Wang, Shuai-Shuai; Cheng, Lei

2014-01-01

368

Hyperbaric oxygenation in peripheral nerve repair and regeneration.  

PubMed

Peripheral nerves are essential connections between the central nervous system and muscles, autonomic structures and sensory organs. Their injury is one of the major causes for severe and longstanding impairment in limb function. Acute peripheral nerve lesion has an important inflammatory component and is considered as ischemia-reperfusion (IR) injury. Surgical repair has been the standard of care in peripheral nerve lesion. It has reached optimal technical development but the end results still remain unpredictable and complete functional recovery is rare. Nevertheless, nerve repair is not primarily a mechanical problem and microsurgery is not the only key to success. Lately, there have been efforts to develop alternatives to nerve graft. Work has been carried out in basal lamina scaffolds, biologic and non-biologic structures in combination with neurotrophic factors and/or Schwann cells, tissues, immunosuppressive agents, growth factors, cell transplantation, principles of artificial sensory function, gene technology, gangliosides, implantation of microchips, hormones, electromagnetic fields and hyperbaric oxygenation (HBO). HBO appears to be a beneficial adjunctive treatment for surgical repair in the acute peripheral nerve lesion, when used at lower pressures and in a timely fashion (<6 hours). PMID:17439703

Sanchez, E Cuauhtemoc

2007-03-01

369

Nerve conduction study of the medial and lateral plantar nerves.  

PubMed

The medial and lateral plantar nerves may be evaluated through the recordings of the compound sensory nerve action potentials (CSNAP), compound mixed nerve action potentials (CMNAP) and compound muscular action potentials (CMAP). As some of these potentials are not easily and always obtainable in normal individuals, our purpose was to verify the consistency of these potentials for the study of these nerves. Fifty-one normal adult volunteers were examined. The CSNAP, CMNAP and CMAP, related to the medial and lateral plantar nerves were evaluated bilaterally. CSNAP were not obtained in 7.8% and in 17.6% from the medial and lateral plantar nerves respectively. CMNAP from the lateral plantar nerve were not obtained in 15.6%. CMNAP from the medial plantar nerves and CMAPs from the abductor hallucis and abductor digiti quinti were obtained for all nerves tested. Our results, therefore, suggest that these last 3 parameters are the ones more reliable for clinical application. PMID:10812535

Antunes, A C; Nobrega, J A; Manzano, G M

2000-01-01

370

Quantitative parameters of facial motor evoked potential during vestibular schwannoma surgery predict postoperative facial nerve function  

Microsoft Academic Search

Background  Facial motor evoked potential (FMEP) amplitude ratio reduction at the end of the surgery has been identified as a good predictor\\u000a for postoperative facial nerve outcome. We sought to investigate variations in FMEP amplitude and waveform morphology during\\u000a vestibular schwannoma (VS) resection and to correlate these measures with postoperative facial function immediately after\\u000a surgery and at the last follow-up.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Intraoperative

Marcus André Acioly; Alireza Gharabaghi; Marina Liebsch; Carlos Henrique Carvalho; Paulo Henrique Aguiar; Marcos Tatagiba

2011-01-01