Volume of Nerve Fibers in the Stress-Induced Bladder of Adult Rats following Capsaicin Treatment

Mammalian Bornavirus (BoDV-1) typically causes a fatal neurologic disorder in horses and sheep, and was recently shown to cause fatal encephalitis in humans with and without transplant reception. It has been suggested that BoDV-1 enters the central nervous system (CNS) via the olfactory pathway. However, (I) susceptible cell types that replicate the virus for successful spread, and (II) the role of olfactory ensheathing cells (OECs), remained unclear. To address this, we studied the intranasal infection of adult rats with BoDV-1 in vivo and in vitro, using olfactory mucosal (OM) cell cultures and the cultures of purified OECs. Strikingly, in vitro and in vivo, viral antigen and mRNA were present from four days post infection (dpi) onwards in the olfactory receptor neurons (ORNs), but also in all other cell types of the OM, and constantly in the OECs. In contrast, in vivo, BoDV-1 genomic RNA was only detectable in adult and juvenile ORNs, nerve fibers, and in OECs from 7 dpi on. In vitro, the rate of infection of OECs was significantly higher than that of the OM cells, pointing to a crucial role of OECs for infection via the olfactory pathway. Thus, this study provides important insights into the transmission of neurotropic viral infections with a zoonotic potential.

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Nimodipine Improves Reinnervation and Neuromuscular Function after Injury to the Recurrent Laryngeal Nerve in the Rat

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348940711600811 ◽

2007 ◽

Vol 116 (8) ◽

pp. 623-630 ◽

Cited By ~ 40

Author(s):

Jonas Hydman ◽

Sten Remahl ◽

Gunnar Björck ◽

Mikael Svensson ◽

Per Mattsson

Keyword(s):

Recurrent Laryngeal Nerve ◽

Motor Neurons ◽

Neuromuscular Junctions ◽

Neuromuscular Function ◽

Nerve Fibers ◽

Laryngeal Nerve ◽

Crush Injury ◽

Adult Rats ◽

Somatotopic Organization ◽

The Impact

Objectives: Injury of the recurrent laryngeal nerve (RLN) is associated with a high degree of neuronal survival, but leads to various levels of vocal fold motion impairment or laryngeal synkinesis, which has been attributed to misdirected reinnervation of the target muscles in the larynx or aberrant, competing reinnervation from adjacent nerve fibers. The aim of the present study was to evaluate the impact of the regeneration-promoting agent nimodipine on reinnervation and neuromuscular function following RLN crush injury. Methods: Sixty adult rats were randomized into nimodipine-treated or untreated groups and then underwent RLN crush injury. Reinnervation of the posterior cricoarytenoid muscle (PCA) was assessed by electrophysiological examination, retrograde tracing of lower motor neurons before and after injury, and quantification of neuromuscular junctions in the PCA muscle. Results: At 6 weeks after injury, the nimodipine-treated animals showed significantly enhanced neuromuscular function and also demonstrated a higher number of motor neurons in the brain stem that had reinnervated the PCA, compared to the untreated animals. The somatotopic organization of ambiguus motor neurons innervating the larynx was similar before injury and after reinnervation. Conclusions: Nimodipine improves regeneration and neuromuscular function following RLN injury in the adult rat, and could be of use in future strategies following RLN injury.

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Involvement of capsaicin-sensitive nerves in regulating the hormone and glucose metabolic response to endotoxin

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1997.273.2.e328 ◽

1997 ◽

Vol 273 (2) ◽

pp. E328-E335 ◽

Cited By ~ 1

Author(s):

A. E. Morgan ◽

C. H. Lang

Keyword(s):

Metabolic Response ◽

Critical Role ◽

Glucose Production ◽

Nerve Fibers ◽

Sensory Nerves ◽

Whole Body ◽

Adult Rats ◽

Glucose Flux ◽

Before And After ◽

Experiment Control

This study investigated the role that sensory nerves play in mediating the hormone and glucose metabolic response to endotoxin [lipopolysaccharide (LPS)]. Adult rats were pretreated subcutaneously with capsaicin to selectively destroy primary sensory afferent nerve fibers. Ten days later, [3-3H]glucose was infused intravenously to assess whole body glucose flux before and after the intravenous injection of Escherichia coli LPS (100 micrograms/100 g body wt). Control animals responded to LPS with characteristic increases in the plasma concentration of glucose (91%) and lactate (threefold) and elevations in the rates of glucose appearance and disappearance (77%). In capsaicin-treated rats, the maximal LPS-induced increase in these parameters was attenuated by 50-60%. In addition, these animals were hypoglycemic at the conclusion of the experiment. Control animals demonstrated early and sustained elevations in circulating levels of corticosterone, glucagon, and catecholamines. In contrast, the early LPS-induced elevation in epinephrine and norepinephrine, and to a lesser extent glucagon, was completely absent or greatly impaired by capsaicin pretreatment. In a separate study, the epinephrine-induced increase in glucose flux was blunted by 75% in capsaicin-treated rats. These data indicate that sensory afferent neurons play a critical role in the early secretory response of glucagon and catecholamines, the maintenance of tissue catecholamine responsiveness, and the stimulation of glucose production after LPS.

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Retinal cross talk in the mammalian visual system

Journal of Neurophysiology ◽

10.1152/jn.01137.2015 ◽

2016 ◽

Vol 115 (6) ◽

pp. 3018-3029 ◽

Cited By ~ 8

Author(s):

Xiaolan Tang ◽

Radouil Tzekov ◽

Christopher L. Passaglia

Keyword(s):

Optic Nerve ◽

Cross Talk ◽

Ganglion Cells ◽

Compound Action Potential ◽

Nerve Fibers ◽

Stray Light ◽

Brown Norway ◽

Bioelectrical Activity ◽

Adult Rats ◽

Full Field

The existence and functional relevance of efferent optic nerve fibers in mammals have long been debated. While anatomical evidence for cortico-retinal and retino-retinal projections is substantial, physiological evidence is lacking, as efferent fibers are few in number and are severed in studies of excised retinal tissue. Here we show that interocular connections contribute to retinal bioelectrical activity in adult mammals. Full-field flash electroretinograms (ERGs) were recorded from one or both eyes of Brown-Norway rats under dark-adapted ( n = 16) and light-adapted ( n = 11) conditions. Flashes were confined to each eye by an opaque tube that blocked stray light. Monocular flashes evoked a small (5–15 μV) signal in the nonilluminated eye, which was named “crossed ERG” (xERG). The xERG began under dark-adapted conditions with a positive (xP1) wave that peaked at 70–90 ms and ended with slower negative (xN1) and positive (xP2) waves from 200 to 400 ms. xN1 was absent under light-adapted conditions. Injection of tetrodotoxin in either eye ( n = 15) eliminated the xERG. Intraocular pressure elevation of the illuminated eye ( n = 6) had the same effect. The treatments also altered the ERG b-wave in both eyes, and the alterations correlated with xERG disappearance. Optic nerve stimulation ( n = 3) elicited a biphasic compound action potential in the nonstimulated nerve with 10- to 13-ms latency, implying that the xERG comes from slow-conducting (W type) fibers. Monocular dye application ( n = 7) confirmed the presence of retino-retinal ganglion cells in adult rats. We conclude that mammalian eyes communicate directly with each other via a handful of optic nerve fibers. The cross talk alters retinal activity in rats, and perhaps other animals.

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IMMUNOHISTOCHEMICAL STUDY OF CALBINDIN IN THE DEVELOPING CEREBELLUM OF THE RAT

Journal of the Grodno State Medical University ◽

10.25298/2221-8785-2020-18-6-692-697 ◽

2020 ◽

Vol 18 (6) ◽

pp. 692-697

Author(s):

O. A. Karnyushko ◽

◽

S. M. Zimatkin ◽

Keyword(s):

Purkinje Cells ◽

Calcium Binding ◽

Age Groups ◽

Physiological Role ◽

Postnatal Period ◽

Nerve Fibers ◽

Adult Rats ◽

White Rats ◽

Calbindin D28k ◽

Developing Cerebellum

Background. Calbindin is a calcium-binding protein that supports calcium homeostasis for the normal functioning of neurons. Purpose. To study the distribution of immunoreactivity of calbindin-D28K in the structures of the developing cerebellum of the rat.Material and methods. The study was performed on 16 outbred white rats of different age groups: 2-, 7-, 15-days (early postnatal period), 45-days (puberty period). The cerebellum samples were taken and fixed in zinc-ethanol-formaldehyde for immunohistochemistry. Calbindin-D28K immunoreactivity was determined on paraffin sections using primary polyclonal rabbit antibodies.Results. In the cerebellar cortex, calbindin immunoreactivity was detected on the 2nd day after development of Purkinje cells (PC) in their perikaryons, and by the 15th day in their dendrites and it did not change by the 45th day. In all terms of the study in PC, it was detected not only in the cytoplasm, but also in their nucleus. In the granular layer, calbindin immunoreactivity decreased in rats in postnatal ontogenesis, however, in adult rats, some neurons were moderately immunopositive. Among them, from the 15th day after birth, the calbindin-immunoreactive afferent nerve fibers running in the white matter were detected. There were no significant differences in the distribution of calbindin between the lobes of the cerebellum of different phylogenetic age. Conclusions. Considering that the expression of сalbindin-D28k is detected throughout the entire period of development of Purkinje cells, as well as its physiological role in maintaining the function and homeostasis of calcium in them, it can be concluded that сalbindin-D28k is a valuable marker for the morphofunctional characteristics of PC in the developing and adult cerebellum of rats in normal and pathological conditions.

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Calibers and microtubules of nerve fibers: differential effect of undernutrition in developing and adult rats

Brain Research ◽

10.1016/0006-8993(90)90544-l ◽

1990 ◽

Vol 509 (2) ◽

pp. 198-204 ◽

Cited By ~ 6

Author(s):

Victor Faúndez ◽

María Elena Cordero ◽

Pedro Rosso ◽

Jaime Alvarez

Keyword(s):

Differential Effect ◽

Nerve Fibers ◽

Adult Rats

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Dynamics of ultrastructural changes in glial cells and nerve fibers of the optic nerve of rats after intra-abdominal injection of a mixture of 40% Ethanol solution and 100% Methanol

Reports of Morphology ◽

10.31393/morphology-journal-2021-27(3)-07 ◽

2021 ◽

Vol 27 (3) ◽

pp. 49-54

Author(s):

N.I. Molchaniuk

Keyword(s):

Optic Nerve ◽

Glial Cells ◽

Structural Changes ◽

Poor Quality ◽

Nerve Fibers ◽

Ethanol Solution ◽

Ultrastructural Changes ◽

Pathological Changes ◽

Adult Rats ◽

Long Term Study

There are, quite often, cases of poisoning of human population with poor-quality alcoholic drinks, which include methanol. The optic nerve, retina and brain tissues are initially affected. A long-term study aimed at identifying initial structural changes in the visual analyzer in the application of various doses of methanol and its mixture with ethanol was carried out. Purpose: to study the dynamics of ultrastructural changes in glial cells and nerve fibers of the optic nerve, which are caused by mixture of ethanol 40% and methanol 100% in a ratio of 3:1 with a dose of methanol of 0.75 g/kg of rat weight. We examined the ultrastructure of the orbit part of the optic nerve of 43 adult rats (Wistar line) in the period from 3 hours to 14 days after one-time intra-abdominal injection of ethanol 40% and methanol 100%, 100% methanol, the dose of methanol is 0.75 g/kg of rat weight. In rats, LD50 is 9.5 g/kg of their weight. It was found out, that within 3 hours after the injection of the mixture of alcohols, the myelin sheath of large-caliber nerve fibers exfoliated, the axoplasm swelled and the mitochondria in their axons pathologically changed, the mitochondria altered in glial cells, which influenced the quality of nerve impulses and axoplasmic transport of substances. In the dynamics of the study, alterative changes in structures of the optic nerve progressed with the complete destruction of part of glial cells by 7 days, mainly in the first 3 days. After the use of methanol 100%, changes in structures of the optic nerve were similar to changes in them after the use of a mixture of alcohols, but with more significant pathology at all periods of observation with the peak of their manifestation on the 7th day. In glial cells and axons of nerve fibers from the 1st day of the study, signs of compensatory and restorative processes were found: they increased protein-synthesizing and energy-forming functions that were aimed at restoring the damaged ultrastructure. It is established, that 3 hours after the injection of a mixture of alcohols, reactive changes in the structures of the optic nerve of rats took place, which from the 1st day develop into pathological changes and are observed up to 14 days with the peak of their activity on the 7th day of the study. After the use of methanol 100%, the ultrastructure of the optic nerve of rats is more damaged than after the injection of a mixture of alcohols. It is proved, that methanol has a leading place in the development of pathological changes in structures of the optic nerve after the injection of a mixture of alcohols.

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Variations of collateral branching in the motor nerve fibers in the skeletal muscle of adult rats

Acta Histochemica ◽

10.1016/s0065-1281(11)80372-7 ◽

1993 ◽

Vol 94 (2) ◽

pp. 173-184 ◽

Cited By ~ 1

Author(s):

Masaru Kawabuchi ◽

Toshio Kosaka

Keyword(s):

Skeletal Muscle ◽

Motor Nerve ◽

Nerve Fibers ◽

Adult Rats

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Multiple functions for NGF receptor in developing, aging and injured rat teeth are suggested by epithelial, mesenchymal and neural immunoreactivity

Development ◽

10.1242/dev.109.2.461 ◽

1990 ◽

Vol 109 (2) ◽

pp. 461-471 ◽

Cited By ~ 2

Author(s):

M.R. Byers ◽

G.C. Schatteman ◽

M. Bothwell

Keyword(s):

Neural Development ◽

Third Molar ◽

Growth Factor Receptor ◽

Mesenchymal Cells ◽

Nerve Fibers ◽

Phenotypic Change ◽

Adult Rats ◽

Dental Lamina ◽

Reparative Dentin ◽

Enamel Epithelium

We have used immunocytochemistry to analyse expression of nerve growth factor receptor (NGFR) in developing, aging and injured molar teeth of rats. The patterns of NGFR immunoreactivity (IR) in developing epithelia and mesenchyme matched the location of NGFR mRNA assayed by in situ hybridization with a complementary S35-labeled RNA probe. The following categories of NGFR expression were found. (1) There was NGFR-IR in the dental lamina epithelium and in adjacent mesenchyme during early stages of third molar formation. (2) NGFR-IR nerve fibers were posterior and close to the bud epithelium. (3) During crown morphogenesis NGFR expression was prominent in internal enamel epithelium and preodontoblasts; it faded as preameloblasts elongated and as odontoblasts began to make predentin matrix; and it was weak or absent from outer enamel epithelium, the cervical loop, and differentiated ameloblasts and odontoblasts. (4) When NGFR-IR nerve fibers entered the molars late in the bell stage, they innervated the most mature peripheral pulp and dentin in an asymmetric pattern which correlated more with asymmetric enamel synthesis than with mesenchymal NGFR-IR distribution. (5) The mesenchymal pulp cells continued to have intense NGFR expression in adult teeth, especially near coronal tubular dentin. (6) The pulpal NGFR-IR decreased in very old rats or subjacent to reparative dentin (naturally occurring or experimentally induced). (7) During root formation, the preodontoblasts had NGFR-IR but most root mesenchymal cells and Hertwig's epithelial root sheath did not. This work suggests that there are important epithelial and mesenchymal targets of NGF regulation during molar morphogenesis that differ for crown and root development and that do not correlate with neural development. The continuing expression of NGFR-IR by pulpal mesenchymal cells in adult rats was most intense near coronal odontoblasts making tubular dentin; and it was lost during aging, or subjacent to sites of dentin injury that caused a phenotypic change in the odontoblast layer.

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