Types Of Nerve Fibers Research Articles

Diabetic neuropathy

Diabetes mellitus is one of the emergency situations worldwide. DM is the most common cause of neuropathy throughout the world that create a wide range of conditions associated with the damage of various nerves and various pathological mechanisms. The article considers the main pathogenetic mechanisms of neuropathy - the role of metabolic, vascular and genetic factors. It presents the main clinical manifestations, depending on what type of nerve fibers are affected. A modern classification of diabetic neuropathy is provided. The most common form - diabetic distal symmetric polyneuropathy is considered in detail. The authors describe the main drugs used for the treatment of diabetic neuropathy, which were proposed by the International Diabetic Federation (2017) in 2017. Lipoic acid supplements are examined in more details.

Nerve fibre infiltration and expression in peritoneal lesions of endometriosis in a nonhuman primate model of endometriosis

Baboon ( Papio anubis) models of endometriosis are thought to mimic the early stages of spontaneous human peritoneal endometriotic disease. The objective of this study was to investigate the presence and course of nerve fibre ingrowth during peritoneal lesion formation in specimens collected at 3 months (early stage of lesion development) and 15 months (late stage of lesion development) after disease initiation compared to pelvic peritoneum (control). Five-micron sections of paraffin-embedded peritoneal lesions were obtained from normally cycling baboons with 3-month (n = 12), 15-month (n = 12) induced endometriosis and pelvic peritoneum (n = 10) from baboons with no endometriosis. Immunohistochemical staining was performed with specific antibodies: protein gene product 9.5 – broad marker of nerve fibres and neurones, neuropeptide Y – sympathetic neurones, substance P – sensory neurones, vasoactive intestinal peptide – parasympathetic neurones, nerve growth factor – development of new neurones and high-affinity receptor for nerve growth factor (tropomyosin receptor kinase A) – neuronal differential. Significantly, more nerve fibres were identified in peritoneal endometriotic lesions collected 15 months after the initiation of experimental protocols compared with 3-month and control samples (p < 0.001). Nerve fibres were immunoreactive for all the tested markers – protein gene product 9.5, neuropeptide Y, substance P, vasoactive intestinal peptide, nerve growth factor and tropomyosin receptor kinase A – indicating the presence of different types of nerve fibres. In conclusion, peritoneal lesions of endometriosis in a nonhuman primate model of endometriosis were found to be progressively and spontaneously innervated by both myelinated and unmyelinated sensory nerve fibres, parasympathetic and sympathetic neurones. These nerve fibres may play an important role in the mechanisms of pain generation in this condition.

Expanded teased nerve fibre pathological conditions in disease association

ObjectiveTo describe an expanded teased nerve fibre classification in disease association.MethodsWe reviewed four newly proposed teased nerve fibre types (Types J–M): Type J, rope-like fibres; K, fibril-like clumps of osmium...

Phenotyping animal models of diabetic peripheral neuropathy in rats: advantages and limitations

Diabetic polyneuropathy is one of the most common late complications of diabetes mellitus, as well as the main cause of ulcerative foot defects. The prevalence of neuropathy among people with diabetes varies from 28 to 65%, depending on the disease duration and diagnostic features. Initial signs of damage are detected as early as in prediabetes. To date, there is a fairly limited knowledge of the mechanisms of nerve fiber damage in diabetes. Also, it is unclear which type of nerve fibers is involved in damage first and how the nervous system regulates repair of tissues and local immunity. Animal models of diabetic peripheral neuropathy enable studying new aspects of the pathogenesis of this common diabetes complication and open prospects for the search and development of new drugs.

Association between Pain Sensitivity, Central Sensitization, and Functional Disability in Adolescents With Joint Hypermobility

PurposeThe purpose of this study was to examine the association between pain sensitivity, central sensitization, and functional disability in adolescents with joint hypermobility. Design and MethodsA cross-sectional descriptive design was utilized for this study. A sample of 40 adolescents being evaluated for chronic pain and autonomic nervous system dysfunction were recruited. Subjects were evaluated for pain, function, central sensitization, and sensitivity on pain and touch sensory nerve fiber types. Data were analyzed to detect associations between variables. ResultsJoint hypermobility had a moderately significant correlation with central sensitization measured by the Central Sensitization Inventory, as well as increased pain sensitivity as evidenced by hypersensitivity of Aδ sensory nerve fibers. The presence of central sensitization was also positively associated with level of functional disability. ConclusionsFindings implicate joint hypermobility as a possible antecedent to pain hypersensitivity and central sensitization syndromes that when recognized and addressed effectively may reduce functional disability in those affected. Practice ImplicationsIt is important for pediatric nurses that work with adolescents that have chronic pain to understand variables that may impact pain and functional disability in order to develop methods to increase function, reduce pain, and increase perceived quality of life.

Identifying central and peripheral nerve fibres with an artificial intelligence approach

Distinguishing axons from central or peripheral nervous systems (CNS or PNS, respectively) is often a complicated task. The main objective of this work was to facilitate and support the process of automatically distinguishing the different types of nerve fibres by analysing their morphological characteristics. Our approach was based on a multi-level hierarchical classifier architecture that can handle the complexity of directly identifying nerve-fibre groups belonging to either the CNS or the PNS. The approach adopted comprises supervised methods (multilayer perceptron and decision trees), which are responsible for distinguishing the origin of the axons (CNS or PNS), whereas the unsupervised method (K-means clustering) performs nerve fibre clustering based on similar characteristics for both the CNS and PNS. Our experiments produced results with an accuracy higher than 88%. Our findings suggest that the development and implementation of a multi-level system improves automation capabilities and increases accuracy in the classification of nerves. Furthermore, our architecture allows for generalisation and flexibility, which can subsequently be extended to other biological control systems.

An immunohistochemical identification key for cell types in adult mouse prostatic and urethral tissue sections.

Though many methods can be used to identify cell types contained in complex tissues, most require cell disaggregation and destroy information about where cells reside in relation to their microenvironment. Here, we describe a polytomous key for cell type identification in intact sections of adult mouse prostate and prostatic urethra. The key is organized as a decision tree and initiates with one round of immunostaining for nerve, epithelial, fibromuscular/hematolymphoid, or vascular associated cells. Cell identities are recursively eliminated by subsequent staining events until the remaining pool of potential cell types can be distinguished by direct comparison to other cells. We validated our identification key using wild type adult mouse prostate and urethra tissue sections and it currently resolves sixteen distinct cell populations which include three nerve fiber types as well as four epithelial, five fibromuscular/hematolymphoid, one nerve-associated, and three vascular-associated cell types. We demonstrate two uses of this novel identification methodology. We first used the identification key to characterize prostate stromal cell type changes in response to constitutive phosphatidylinositide-3-kinase activation in prostate epithelium. We then used the key to map cell lineages in a new reporter mouse strain driven by Wnt10aem1(cre/ERT2)Amc. The identification key facilitates rigorous and reproducible cell identification in prostate tissue sections and can be expanded to resolve additional cell types as new antibodies and other resources become available.

Structural Organization and Interaction of Intrapancreatic Ganglia with the Myenteric Nerve Plexus of the Duodenum at the Early Stages of Postnatal Ontogeny in Rats

Studies using immunohistochemical markers – synaptophysin (SP), protein gene product 9.5 (PGP 9.5), and tyrosine hydroxylase (TH) – addressed the innervation of the pancreas and the myenteric nerve plexus of the duodenum (duodenum) in neonatal rats (n = 4) and demonstrated a tight link between the nerve plexuses in these organs. Some elements of the myenteric plexus penetrate the pancreas from the walls of the duodenum. Morphological and biochemical similarity was demonstrated between microganglia in the myenteric plexus of the duodenum and pancreas. Most differentiated neurons and bundles of axons in both plexuses were part of the parasympathetic compartment of the autonomic nervous system. There were no catecholaminergic neurons in the pancreas, and bundles of sympathetic fibers entering the organ from outside were few in number and were involved mainly in innervating blood vessels. This is the first report of the use of immunohistochemical reactions for PGP 9.5, SP, and TH to detect two types of nerve fibers in ganglia in the pancreas whose varicose terminals form cholinergic and catecholaminergic synapses around nerve cell bodies.

A mouse model for pain and neuroplastic changes associated with pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) continues to be one of the deadliest human malignancies and is associated with excruciating pain, which is a serious complication and severely impacts the quality of life in patients. In human patients, poor survival prognosis is linked to remarkable remodeling of intrapancreatic nerves, which, in turn, is correlated to increased pain intensity. Understanding mechanisms underlying pain associated with PDAC has been hampered by the lack of animal models which replicate all germane aspects of the disease and importantly, enable analyses of pain associated with PDAC. In this study, we describe an immunocompetent orthotopic mouse model of PDAC involving intrapancreatic growth of K8484 mouse PDAC cells, which reliably exhibits a large number of key characteristics of human PDAC, including its unique histopathology and neuroplastic changes. We observed that tumor-bearing mice demonstrated significant abdominal mechanical hypersensitivity to von Frey stimuli as well as on-going pain in the conditioned place preference paradigm. Moreover, a myriad of other behavioral tests revealed that indicators of overall well-being were significantly reduced in tumor-bearing mice as compared to sham mice. Morphological and immunohistochemical analyses revealed structural remodeling in several different types of sensory and autonomic nerve fibers. Finally, perineural invasion of tumor cells, a cardinal manifestation in human PDAC, was also observed in our orthotopic mouse model. Thus, we describe a validated tumor model for quantitatively testing hypersensitivity and pain in PDAC, which lays a crucial basis for interrogating tumor-nerve interactions and the molecular and cellular mechanisms underlying pain in PDAC.

Eficácia e efeitos hemodinâmicos da anestesia raquidiana com ropivacaína isobárica, hipobárica ou hiperbárica em cães anestesiados com isofluorano

RESUMO: O presente estudo objetivou avaliar a anestesia raquidiana com ropivacaína em cães alterando a baricidade do anestésico local, investigando as alterações hemodinâmicas e complicações. Foram utilizados seis cães, Beagle, 4 anos, submetidos a anestesia inalatória com isofluorano e aos tratamentos: Ghipo = anestesia raquidiana hipobárica (0,5 mL NaCl 0,9% + 0,5 mL ropivacaína 0,75%); Giso = anestesia raquidiana isobárica (0,5 mL NaCl 1,53% + 0,5 mL ropivacaína 0,75%); Ghiper = anestesia raquidiana hiperbárica (0,5 mL glicose 10% + 0,5 mL ropivacaína 0,75%). Após indução anestésica e manutenção com isofluorano, os animais foram posicionados em decúbito lateral direito para a passagem de um cateter de artéria pulmonar pela veia jugular esquerda. Após esse procedimento, a punção subaracnóide foi realizada entre L5-L6 com uma agulha espinhal 22G, seguida da administração de 1 mL de anestésico local em 1 min. Os animais foram mantidos por 60 minutos anestesiados em decúbito ventral. A FC, f, PAM, DC, PAPm e TºC apresentaram aumento progressivo em todos os grupos enquanto que a PCPm, apenas no GHIPO, aumentou ao longo de todos os momentos. O IRPT no GISO apresentou valores significativamente superiores no M1, M5 e M10 comparado aos demais grupos, exceto no M5, em que o GISO diferiu somente do GHIPER. O IRVP no GISO aumentou no M5 em comparação ao MB. Foram observados efeitos adversos como déficit motor unilateral, atonia vesical, excitação, dor aguda e quemose. De acordo com os dados obtidos no presente estudo pode-se concluir que os animais que receberam anestesia raquidiana com as soluções hiperbárica e isobárica apresentaram maior bloqueio motor comprovando que a baricidade influencia diretamente o tipo de fibra a ser bloqueada. A utilização de solução isobárica resulta em um bloqueio misto (motor e sensitivo). As alterações hemodinâmicas descritas na literatura como, bradicardia e hipotensão, não puderam ser evidenciadas neste estudo embora o volume de anestésico tenha sido baixo associado a influência dos efeitos do isofluorano. Em relação às complicações evidenciadas, sugere-se acompanhamento pós-anestésico dos animais submetidos à anestesia raquidiana a fim de que quaisquer alterações possam ser identificadas precocemente e tratadas.

Somatic neural alterations in non-diabetic obesity: a cross-sectional study.

BackgroundReports on alterations in somatic neural functions due to non-diabetic obesity, a major risk factor for diabetes, are few and still a matter of debate. Nevertheless, to our knowledge, reports lack any comments on the type of somatic nerve fibers affected in non-diabetic obesity. Therefore, this study aimed to find out the alteration in somatic neural functions in non-diabetic obese persons if any.MethodsThe study was conducted on 30 adult non-diabetic obese persons (mean age 32.07 ± 7.25 years) with BMI > 30 Kg/m2 (mean BMI 30.02 ± 2.89 Kg/m2) and 29 age- and sex-matched normal weight controls (mean age 30.48 ± 8.01 years) with BMI: 18–24Kg/m2 (mean BMI 21.87 ± 2.40 Kg/m2). Nerve conduction study (NCS) variables of median, tibial and sural nerves were assessed in each subject using standard protocol. The data were compared by Mann Whitney ‘U’ test.ResultsIn comparison to normal weight persons, obese had lower compound muscle action potential (CMAP) amplitudes of right median [9.09(7.62–10.20) Vs 10.75(8.71–12.2) mV, p = 0.025] and bilateral tibial nerves [Right: 8.5(7.04–11.18) Vs 12.1(10.55–15) mV, p < 0.001 and left 9.08(6.58–11.65) Vs 13.05(10.2–15.6) mV, p = 0.002]. Furthermore, obese persons had prolonged CMAP durations of right and left median [10.5(9.62–12) Vs 10(8.4–10.3) ms, p = 0.02 and 10.85(10–11.88) Vs 10(9–10.57) ms, p = 0.019] and right tibial [10(9–11) 8.5(7.92–10) ms, p = 0.032] nerves. Sensory NCS (sural nerve) also showed diminished sensory nerve action potential (SNAP) amplitude [16(12.08–18.21) vs 22.8(18.3–31.08) μV, p < 0.001] and prolonged duration. However, onset latencies and conduction velocities for all nerves were comparable between the groups.ConclusionThis study documents subclinical peripheral nerve damage in non-diabetic obese with abnormal NCS parameters; shorter amplitudes and prolonged CMAP and SNAP durations. The reduced amplitudes of mixed and sensory nerves might be due to decreased axonal number stimulation or actual decrease in number of axonal fibers, or defect at NMJ in non-diabetic obese. Prolonged durations but normal onset latencies and conduction velocities strongly suggest involvement of slow conducting fibers.

Distribution and sub-types of afferent fibre in the mouse urinary bladder

AimIncreased afferent fibre activity contributes to pathological conditions such as the overactive bladder syndrome. Nerve fibres running near the urothelium are considered to be afferent as no efferent system has yet been described. The aim of this study was to identify sub-types of afferent nerve fibres in the mouse bladder wall based on morphological criteria and analyse regional differences. Materials and methods27 bladders of six month old C57BL/6 mice were removed and tissues were processed for immunohistochemistry. Cryostat sections were cut and stained for Protein Gene Product 9.5 (PGP), calcitonin gene related polypeptide (CGRP), neurofilament (NF), vesicular acetylcholine transporter (VAChT) and neuronal nitric oxide synthase (nNOS). ResultsIn the sub-urothelium, different types of afferent nerve fibre were found, i.e. immunoreactive (IR) to; CGRP, NF, VAChT, and/or nNOS. At the bladder base, the sub-urothelium was more densely innervated by CGRP-IR and VAChT-IR nerve fibres, then at the lateral wall. NF- and nNOS nerves were sparsely distributed in the sub-urothelium throughout the bladder. At the lateral wall the inner muscle is densely innervated by CGRP-IR nerve fibres. NF, VAChT and nNOS nerves were evenly distributed in the different muscle layers throughout the bladder. Nerve fibre terminals expressing CGRP and NF were found within the extra-mural ganglia at the bladder base. ConclusionsDifferent types of afferent nerve fibres were identified in the sub-urothelium of the mouse bladder. At the bladder base the sub-urothelium is more densely innervated than the lateral wall by CGRP-IR and VAChT-IR afferent nerve fibres. CGRP and NF afferent nerve fibres in the muscle layer probably relay afferent input to external ganglia located near the bladder base. The identification of different afferent nerves in the sub-urothelium suggests a functional heterogeneity of the afferent nerve fibres in the urinary bladder.

Corneal nerve activity during ocular inflammatory processes

PurposeTo study the changes in sensory nerve activity of the eye associated with ocular inflammation in two different experimental models developed in the guinea‐pig.MethodsAllergic keratoconjunctivitis (AK): Ovalbumin sensitization was induced and blinking and tearing rate was measured before and after the allergic challenge. UV photokeratitis: One eye of the anesthetized guinea‐pig was exposed to 254 nm radiation during different times. Blinking rate and tear secretion were measured before and 48 h after UV. In both models, nerve activity was recorded in vitro in the whole eye or the excised cornea superfused with physiological saline at a controlled temperature. Spontaneous (SA) and stimulus‐evoked electrical activity were recorded. Mechanical, thermal and chemical sensitivity were tested in control and inflamed eyes.ResultsIn AK model tearing and blinking rate increased significantly. In nociceptors, mechanical threshold decreased, the percentage of units with SA increased and the impulse response to chemical stimulation increased significantly in inflamed eyes compared with controls. On the contrary, SA and response to cold of cold thermoreceptors decreased during inflammation.ConclusionsIn ocular pathological processes primarily characterized by local inflammation, nociceptors became sensitized while cold thermoreceptors became desensitized, due to changes in the expression and/or activity of ion channels present in sensory nerve terminals. Disbalance in the sensory input from the different functional types of sensory nerve fibers innervating the ocular surface in inflammatory conditions may be in the bases of the unpleasant sensations evoked by inflammatory pathological processes affecting the ocular surface in humans.

The role of particulate guanylyl cyclase B (GC-B) in auditory function in adult mice

Background cGMP signaling triggered by the binding of C-type natriuretic peptide (CNP) to its receptor guanylyl cyclase B (GC-B; NPR2; NPRB) has been linked by genetic evidence to a remarkable variety of physiological functions like skeletal bone growth, female fertility, cardiac growth, fat metabolism and gastrointestinal function. For the nervous system it has been recently demonstrated that the CNP/GC-B/cGMP/cGMP-dependent protein kinase type I (cGKI) signaling pathway is essential for sensory axon branching at the dorsal root entry zone of the spinal cord and at the rhombomeres of the hindbrain during embryonic development [1]. Also in the auditory system, distinct auditory nerve fiber (ANF) types that differ in their discharge rate and sound sensitivity bifurcate in the cochlear nucleus (CN), sending collaterals to the anteroventral, posteroventral, and dorsal subdivisions. The lack of GC-B has been shown to lead to a central phenotype [2].

Functional evaluation of peripheral nerve regeneration and target reinnervation in animal models: a critical overview.

Peripheral nerve injuries usually lead to severe loss of motor, sensory and autonomic functions in the patients. Due to the complex requirements for adequate axonal regeneration, functional recovery is often poorly achieved. Experimental models are useful to investigate the mechanisms related to axonal regeneration and tissue reinnervation, and to test new therapeutic strategies to improve functional recovery. Therefore, objective and reliable evaluation methods should be applied for the assessment of regeneration and function restitution after nerve injury in animal models. This review gives an overview of the most useful methods to assess nerve regeneration, target reinnervation and recovery of complex sensory and motor functions, their values and limitations. The selection of methods has to be adequate to the main objective of the research study, either enhancement of axonal regeneration, improving regeneration and reinnervation of target organs by different types of nerve fibres, or increasing recovery of complex sensory and motor functions. It is generally recommended to use more than one functional method for each purpose, and also to perform morphological studies of the injured nerve and the reinnervated targets.

Subacute Sensorimotor Polyneuropathy Associated with Autoimmune Hepatitis.

Dear Editor, Autoimmune hepatitis (AIH) is a chronic immune-mediated liver disorder with unknown etiology that is characterized by seropositivity for autoantibodies and responsiveness to immunosuppressive treatment.1 AIH is frequently associated with other autoimmune diseases,2 and there have been rare reports of associated peripheral neuropathies. A 43-year-old woman was admitted to our hospital because of epigastric pain, abdominal distension, dark urine, and yellow sclera with a duration of 2 months. Laboratory studies revealed elevated liver enzymes and positivity for anti-smooth-muscle antibody and antinuclear antibodies. Liver biopsy findings were compatible with AIH. She was treated with oral methyl-prednisolone (40 mg daily), which normalized liver enzymes within 2 weeks. The patient was referred to the neurology department because of combined sensory loss and weakness. Ascending-type sensory loss had started 1 month before admission. Two weeks later she complained of severe burning pain and paresthesia in both the feet and hands. The weakness in both legs had progressed since 4 days before admission. A neurologic examination revealed mild weakness of both legs [Medical Research Council (MRC) grade 4]; almost completely impaired touch, vibration, and proprioception sensations in both legs, without pain or temperature sensory involvement; generalized hypoactive deep tendon reflexes; and difficulty performing the heel-to-shin test. The initial nerve conduction study (NCS) revealed bilateral mild slowing of nerve conduction in the peroneal nerves, and an inability to elicit nerve action potentials in the sural nerves on both sides. Electromyography revealed cervical and lumbosacral radiculopathy with active denervation and reduced recruitment pattern; there was no evidence of myopathy. The patient was negative for the following ganglioside antibodies: anti-GM1, anti-GD1b, and anti GQ1b. The results of a cerebrospinal fluid study were normal. Despite receiving corticosteroid treatment, the limb weakness progressed rapidly, so that on treatment day 10 the power in both legs was MRC grade 2, and that in both arms was MRC grade 4. The NCS results indicated progression of the polyneuropathy (Table 1). Intravenous immunoglobulin (IVIG) was administrated at a dose of 0.4 g/kg body weight/day for 5 days, which resulted in a dramatic improvement in the leg weakness to MRC grade 4+ after 3 days. Prednisolone maintenance therapy and rehabilitation resulted in the patient being able to stand with assistance 1 month later. Proprioception was also slightly improved, and the pain was diminished. The NCS profile and motor power were further improved 2 months later, but issues with vibration and proprioception persisted. Table 1 Nerve conduction study AIH-related peripheral neuropathy has been rarely reported among the various clinical manifestations, which include chronic inflammatory demyelinating polyneuropathy,3 mononeuritis multiplex,2 motor-axonal polyneuropathy,4 and sensory neuronopathy.5 Immunosuppressive agents have been reported to be effective in several patients. This implies that the peripheral neuropathy associated with AIH is mediated by the immune system. The temporal pattern of progression appears to reveal an interesting feature of AIH-associated polyneuropathy: the initial predominant involvement of the large sensory fibers, leading to sensory ataxia, with the defects in vibration and pro prioception being followed by severe burning pain and then weakness, suggesting the increasing involvement of small fibers and motor nerve fibers. This pattern of progression led us to speculate that there is a gradient in susceptibility among different types of nerve fibers in the disease process. Oral prednisolone alone was not effective in treating the polyneuropathy in our patient, but the weakness was dramatically improved by IVIG. IVIG works effectively in many autoimmune neuromuscular diseases by interfering with the immune regulatory network.6 Therefore, IVIG would be an option for the rapidly progressing neuropathy associated with AIH. AIH-related neuropathy is extremely rare, but it is important to identify this condition in AIH patients with neurologic signs because of its responsiveness to immunotherapy. Further studies with more cases are needed to clarify its pathomechanism and clinical characteristics.

Characterization of Pain in Familial Amyloid Polyneuropathy

Familial amyloid polyneuropathy (FAP) caused by transthyretin (TTR) mutation is a small-fiber predominant polyneuropathy, exposing patients with TTR-FAP to development of neuropathic pain. However, the painful nature of TTR-FAP has never been specifically addressed. In this study, we compared 2 groups of 16 patients with either painless or painful TTR-FAP with regard to various clinical and neurophysiologic variables, including laser evoked potential (LEP) recording and quantitative sensory testing. The 2 groups of patients did not differ on any clinical or neurophysiologic variable. Patients with painful TTR-FAP complained of ongoing burning pain sensations, pain aggravation at rest, paroxysmal pain (electric shock and stabbing sensations), or provoked pain (mostly dynamic mechanical allodynia). However, the symptomatic presentation of painful TTR-FAP evolved with the course of the disease. The duration of the disease and the severity of small-fiber lesions (increase in thermal thresholds and reduction in LEP amplitude) correlated negatively with the intensity of ongoing burning sensations and positively with the intensity of paroxysmal pain. In addition, small-fiber preservation correlated positively with cold allodynia and pain aggravation at rest and negatively with dynamic mechanical allodynia. Peripheral sensitization of small-diameter nociceptive axons might occur in early TTR-FAP and be responsible for the burning sensation and cold allodynia. As polyneuropathy and small-fiber loss progress, paroxysmal pain and dynamic mechanical allodynia may develop as a result of central sensitization generated by abnormal activities affecting relatively spared large-diameter sensory fibers. PerspectivePain in TTR-FAP includes several mechanisms varying with the course of the disease and the involvement of the different types of nerve fibers.

Determinants of nerve conduction recovery after nerve injuries: Compression duration and nerve fiber types.

The aims of this study were to determine the influences of: (1) timing of nerve decompression; and (2) nerve fiber types on the patterns of nerve conduction studies (NCS) after nerve injury. Nerve conduction studies (NCS) were performed on 3 models of nerve injury: (1) crush injury due to transient nerve compression (crush group); (2) chronic constriction injury (CCI), or permanent compression (CCI group); and (3) CCI with removal of ligatures, or delayed nerve decompression (De-CCI group). There were distinct patterns of NCS recovery. The crush and De-CCI groups achieved similar motor nerve recovery, better than that of the CCI group. In contrast, recovery of sensory nerves was limited in the CCI and De-CCI groups and was lower than in the crush group. Immediate relief of compression resulted in the best recovery of motor and sensory nerve conduction. In contrast, delayed decompression restored only motor nerve conduction.

Effect of human umbilical cord mesenchymal stem cells transplantation on nerve fibers of a rat model of endometriosis.

Endometriosis is a common, benign, oestrogen-dependent, chronic gynaecological disorder associated with pelvic pain and infertility. Some researchers have identified nerve fibers in endometriotic lesions in women with endometriosis. Mesenchymal stem cells (MSCs) have attracted interest for their possible use for both cell and gene therapies because of their capacity for self-renewal and multipotentiality of differentiation. We investigated how human umbilical cord-MSCs (hUC-MSCs) could affect nerve fibers density in endometriosis. In this experimental study, hUC-MSCs were isolated from fresh human umbilical cord, characterized by flow cytometry, and then transplanted into surgically induced endometriosis in a rat model. Ectopic endometrial implants were collected four weeks later. The specimens were sectioned and stained immunohistochemically with antibodies against neurofilament (NF), nerve growth factor (NGF), NGF receptor p75 (NGFRp75), tyrosine kinase receptor-A (Trk-A), calcitonin gene-related peptide (CGRP) and substance P (SP) to compare the presence of different types of nerve fibers between the treatment group with the transplantation of hUC-MSCs and the control group without the transplantation of hUC-MSCs. There were significantly less nerve fibers stained with specific markers we used in the treatment group than in the control group (p<0.05). MSC from human umbilical cord reduced nerve fiber density in the treatment group with the transplantation of hUC-MSCs.

PD36-10 MICROANATOMY AND INNERVATION PATTERNS OF THE SPERMATIC CORD IN HUMANS

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research II1 Apr 2015PD36-10 MICROANATOMY AND INNERVATION PATTERNS OF THE SPERMATIC CORD IN HUMANS Koji Shiraishi, Shintaro Oka, and Hideyasu Matsuyama Koji ShiraishiKoji Shiraishi More articles by this author , Shintaro OkaShintaro Oka More articles by this author , and Hideyasu MatsuyamaHideyasu Matsuyama More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.2259AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Understanding of the spermatic microanatomy is important during the microsurgical denervation of the spermatic cord (MDSC) and varicocelectomy. Anatomical information regarding spermatic vessels has been well documented; however, the locations of the lymphatics and nerves and the types of nerve fibers have been poorly investigated. The purposes of this study are to document the distribution of lymphatics and nerves and identify the types of nerve fibers in the human spermatic cord. METHODS Between August 2013 and August 2014, a total of 33 men (17 to 43 years old) underwent microsurgical inguinal varicocelectomy (n=23) or MDSC (n=10) and agreed with the purpose of this study. The outer half of the spermatic fascia was resected intraoperatively to 2 cm, fixed with formalin and immunostained with antibodies against a lymphatic marker D2-40, a pan-neuronal marker PGP9.5, a sympathetic marker tyrosine hydroxylase (TH), a parasympathetic marker vasoactive intestinal polypeptide (VIP), and a sensory nociceptor marker calcitonin gene-related peptide (CGRP). The innervation density was examined in patients subdivided according to the presence of orchalgia. The same analyses were performed using the whole sections of the spermatic cord that were obtained from 10 patients with testicular cancer who had undergone an orchiectomy. RESULTS The spermatic fascia was composed of mainly smooth muscle fibers. The mean number of lymphatics in the spermatic fascia was 0.4, and lymphatics were found in 26% of the men. The majority of lymphatics were localized in the intraspermatic cord. The mean number of nerve fibers that were positive for PGP9.5 in the spermatic fascia was 7.2. Ninety percent of the PGP9.5-positive fibers were also positive for CGRP, and 75% of the fibers were positive for TH but not for VIP. The number of CGRP-positive fibers was significantly higher in men with orchalgia than in men without orchalgia (p<0.05). In the spermatic cord, both PGP9.5- and TH-positive fibers were distributed (mean number: 8.9), and the distribution of the CGRP fibers in the intraspermatic cord was sparse, except for around the vas. CONCLUSIONS The CGRP-positive sensory nerve is considered to be involved in the pathophysiology of chronic orchalgia, and the transection of spermatic fascia and nerve fibers around the vas is extremely important during MDSC. The post-operative scrotal hydrocele may not be a problem if several lymphatics are preserved in the spermatic cord. Sympathetic fibers in the spermatic fascia and cord may contribute to the contraction of spermatic muscle and testicular blood regulation. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e768-e769 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Koji Shiraishi More articles by this author Shintaro Oka More articles by this author Hideyasu Matsuyama More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...