SCIATIC NERVE

Objective: To determine the number, size, somatotopy and segmental distribution of HRP labeledmotor and sensory neurons forming sciatic nerve in albino rat by using HRP technique. To fined out the distribution ofneurons in sciatic nerve in albino rat in spinal cord from L3S1. The average number, size and segmental distribution ofmotor and sensory neurons were localized by HRP method of tracing neuronal connections. The motor neurons formingSCN ranged 10-60 microns and extended between the caudal part of L3 and rostral part of SI spinal segment. Theyoccupied PPL, PL, C and aL subgroups. The peak frequency distribution of motor neurons was observed in L4-L6spinal segment in SCN. The labeled sensory neurons whose peripheral process run in SCN were localized in L3-S1ipsilateral Dorsal Root Ganglia (DRG). No somatotopic organization of the cells was found in the DRG. The cells weredistributed throughout the ganglia without forming groups. The somal diameters of sensory neurons forming SCNmeasured between 14-58 microns.

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Review for "Intrinsic sensory neurons provide direct input to motor neurons and interneurons in mouse distal colon via varicose baskets"

10.1002/cne.24872/v2/review1 ◽

2020 ◽

Author(s):

Winfried Neuhuber

Keyword(s):

Sensory Neurons ◽

Motor Neurons ◽

Distal Colon ◽

Direct Input

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Prevention and Healing of Calcium Signaling Mediated Neuronal Damage on successive Administration of Flavonoid Enriched Pterocarpus Marsupium Roxb in Peripheral Neuropathy Model

Current Bioactive Compounds ◽

10.2174/1573407216666200218112305 ◽

2020 ◽

Vol 16 (9) ◽

pp. 1346-1355

Author(s):

Neethi Shaju ◽

Mrinmoy Gautam ◽

Abdul Khayum ◽

Gunasekaran Venkatesh

Keyword(s):

Neuropathic Pain ◽

Peripheral Neuropathy ◽

Sciatic Nerve ◽

Motor Neurons ◽

Neuronal Damage ◽

Interleukin 10 ◽

Central Mechanism ◽

Behavioral Models ◽

Cell Hyperplasia ◽

Pterocarpus Marsupium

Background: Modern research on peripheral neuropathy circumstance utter that treatments with Vincristine (VCR) disturb the microtubular cells in sensory and motor neurons due to calcium over- load in sciatic nerve, unfortunately, VCR triggering the release of Tumor necrosis factor-α (TNFα) in central neurons causes excitotoxicity as well. Although ethnomedical information specifies that Pterocarpus marsupium Roxb (PM) is widely used for various nervous disorders, not yet justified on VCR induced peripheral neuropathy and in relation to central mechanism. Objective: This study is aimed to explore the possible central and peripheral mechanism of flavonoid enriched PM in VCR induced neuropathy model. Methods: Neuropathic pain was induced in female Wistar rats by VCR (75μg/ kg/day, i.p) for 10 days. Nociceptive thresholds were assessed by subjecting them to behavioral and biochemical estimation, proinflammatory cytokines along with morphological evaluation. Results: PM significantly increased the nociceptive threshold evident from various behavioral models in comparison to VCR group. More importantly, PM significantly reversed the VCR induced calcium elevation, glutamate and aspartate release in the brain. Discussion: It was also observed that the raised TNF-α, Interleukin-1β were controlled and interleukin- 10 was elevated in sciatic nerve after PM treatment. Evident from histology, PM markedly reversed the VCR induced axonal degeneration, Schwann cell hyperplasia, and myelin fibrosis. Conclusion: Flavonoid enriched PM both 100 & 200mg/kg post and co-administration exerted a preventive and curative effect in VCR induced neuropathic pain by controlling calcium-mediated excitotoxicity through peripheral and central mechanism.

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Connections between thoraco-coxal proprioceptive afferents and motor neurons in the locust

Journal of Experimental Biology ◽

10.1242/jeb.203.3.435 ◽

2000 ◽

Vol 203 (3) ◽

pp. 435-445

Author(s):

M. Wildman

Keyword(s):

Electrical Stimulation ◽

Sensory Neurons ◽

Motor Neurons ◽

Chordotonal Organ ◽

Synaptic Connections ◽

Afferent Neurons ◽

Postsynaptic Potentials ◽

The Common ◽

Proprioceptive Afferents ◽

Stimulation Of

The position of the coxal segment of the locust hind leg relative to the thorax is monitored by a variety of proprioceptors, including three chordotonal organs and a myochordotonal organ. The sensory neurons of two of these proprioceptors, the posterior joint chordotonal organ (pjCO) and the myochordotonal organ (MCO), have axons in the purely sensory metathoracic nerve 2C (N2C). The connections made by these afferents with metathoracic motor neurons innervating thoraco-coxal and wing muscles were investigated by electrical stimulation of N2C and by matching postsynaptic potentials in motor neurons with afferent spikes in N2C. Stretch applied to the anterior rotator muscle of the coxa (M121), with which the MCO is associated, evoked sensory spikes in N2C. Some of the MCO afferent neurons make direct excitatory chemical synaptic connections with motor neurons innervating the thoraco-coxal muscles M121, M126 and M125. Parallel polysynaptic pathways via unidentified interneurons also exist between MCO afferents and these motor neurons. Connections with the common inhibitor 1 neuron and motor neurons innervating the thoraco-coxal muscles M123/4 and wing muscles M113 and M127 are polysynaptic. Afferents of the pjCO also make polysynaptic connections with motor neurons innervating thoraco-coxal and wing muscles, but no evidence for monosynaptic pathways was found.

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The role of interneurons in controlling the tail-withdrawal reflex in Aplysia: a network model

Journal of Neurophysiology ◽

10.1152/jn.1993.70.5.1777 ◽

1993 ◽

Vol 70 (5) ◽

pp. 1777-1786 ◽

Cited By ~ 14

Author(s):

J. A. White ◽

I. Ziv ◽

L. J. Cleary ◽

D. A. Baxter ◽

J. H. Byrne

Keyword(s):

Synaptic Plasticity ◽

Sensory Neurons ◽

Network Model ◽

Motor Neurons ◽

Excitatory Postsynaptic Potential ◽

Layer Model ◽

Neural Network Models ◽

Plastic Properties ◽

Withdrawal Reflex ◽

Long Duration

1. The contributions of monosynaptic and polysynaptic circuitry to the tail-withdrawal reflex in the marine mollusk Aplysia californica were assessed by the use of physiologically based neural network models. Effects of monosynaptic circuitry were examined by the use of a two-layer network model with four sensory neurons in the input layer and one motor neuron in the output layer. Results of these simulations indicated that the monosynaptic circuit could not account fully for long-duration responses of tail motor neurons elicited by tail stimulation. 2. A three-layer network model was constructed by interposing a layer of two excitatory interneurons between the input and output layers of the two-layer network model. These interneurons had properties mimicking those of the recently described interneuron LP117, receiving excitatory input from pleural sensory neurons and evoking a biphasic excitatory postsynaptic potential (EPSP) in pedal motor neurons (Cleary and Byrne 1993). The three-layer model could account for long-duration responses in motor neurons. 3. Sensory neurons are a known site of plasticity in Aplysia. Synaptic plasticity was incorporated into the three-layer model by altering the magnitudes of conductance changes evoked in motor neurons and interneurons by presynaptic sensory neurons. In these simulations the excitatory interneurons converted an amplitude-coded input into an amplitude- and duration-coded output, allowing the three-layer network to support a large range of output amplitudes and durations. 4. Synaptic plasticity at more than one locus modified dramatically the input-output relationship of the three-layer network model. This feature gave the model redundancy in its plastic properties and points to the possibility of distributed memory in the circuitry mediating withdrawal reflexes in Aplysia. Multiple sites of control over the response of the network would likely allow a more diverse repertoire of responses.

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Sensitization of the gill and siphon withdrawal reflex of Aplysia: multiple sites of change in the neuronal network

Journal of Neurophysiology ◽

10.1152/jn.1993.70.3.1210 ◽

1993 ◽

Vol 70 (3) ◽

pp. 1210-1220 ◽

Cited By ~ 23

Author(s):

L. E. Trudeau ◽

V. F. Castellucci

Keyword(s):

Sensory Neuron ◽

Sensory Neurons ◽

Motor Neurons ◽

Neuronal Network ◽

Feedback Inhibition ◽

Excitatory Input ◽

Major Mechanism ◽

Withdrawal Reflex ◽

The Difference ◽

Central Synapses

1. Recent studies have emphasized the major contribution of interneuronal transmission to the mediation and learning-associated modulation of the gill and siphon withdrawal (GSW) reflex of Aplysia. We wish to provide more direct support for the hypothesis that inhibitory junctions are crucial sites of plasticity. 2. In parallel experiments we investigated modulation at five major sites of synaptic transmission in the GSW network: 1) from sensory neurons to motor neurons, 2) from sensory neurons to excitatory interneurons (INTs+) 3) from INTs+ to motor neurons (MNs), 4) from inhibitory interneurons (INTs-) to INTs+, and 5) from INTs+ to INTs-. 3. While recording simultaneously from a single sensory neuron of the LE cluster, an INT+, and a MN, we found that both LE-MN and LE-INTs+ synapses were facilitated by the activation of modulator neurons by stimulation of the left pleuroabdominal connective (185 and 93%, respectively) as well as by serotonin (5-HT) (191 and 84%). Junctions of the second type were therefore less facilitated. The difference in the magnitude of facilitation at these two sites is an indication of a branch-specific, differential efficacy in the modulation of different central synapses made by a single neuron. 4. Although INT(+)-MN junctions have the capacity to display marked posttetanic potentiation, they are not significantly potentiated after connective stimulation. Sensitization of the GSW reflex is therefore not necessarily accompanied by a modification of transmission at these synapses. 5. Inhibitory transmission to INTs+ is significantly reduced by connective stimulation (36%) and by 5-HT (71%). This supports the hypothesis that a reduction of feedback inhibition into INTs+ is a major mechanism of reflex sensitization and may account for the increased evoked firing of INTs+ that is observed after connective stimulation. 6. The excitatory input to INTs- is selectively decreased by 5-HT (50%) and by the molluscan neuropeptide small cardioactive peptide B (38%). This latter effect, which could produce disinhibition of INTs+, may explain the previous observation that this peptide is able to potentiate the evoked input to MNs of the reflex at a concentration (1 microM) that fails to modify monosynaptic sensory-motor transmission. 7. These results indicate that transmission through a small neuronal network that mediates a withdrawal reflex in Aplysia may be modulated at multiple sites and by different mechanisms. These mechanisms include: 1) branch-specific facilitation of sensory neuron outputs and 2) inhibition of INT(-)-INT+ inhibitory postsynaptic potentials by endogenous modulatory neurons and by 5-HT.(ABSTRACT TRUNCATED AT 400 WORDS)

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Identification and characterization of pleural neurons that inhibit tail sensory neurons and motor neurons in Aplysia: correlation with FMRFamide immunoreactivity

Journal of Neuroscience ◽

10.1523/jneurosci.14-06-03565.1994 ◽

1994 ◽

Vol 14 (6) ◽

pp. 3565-3577 ◽

Cited By ~ 12

Author(s):

Y Xu ◽

LJ Cleary ◽

JH Byrne

Keyword(s):

Sensory Neurons ◽

Motor Neurons ◽

Identification And Characterization

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Midkine expression in rat spinal motor neurons following sciatic nerve injury

Developmental Brain Research ◽

10.1016/j.devbrainres.2004.09.006 ◽

2004 ◽

Vol 153 (2) ◽

pp. 251-260 ◽

Cited By ~ 18

Author(s):

Harutoshi Sakakima ◽

Yoshihiro Yoshida ◽

Kenji Kadomatsu ◽

Yukio Yuzawa ◽

Seiichi Matsuo ◽

...

Keyword(s):

Sciatic Nerve ◽

Nerve Injury ◽

Motor Neurons ◽

Sciatic Nerve Injury ◽

Spinal Motor Neurons ◽

Spinal Motor

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Differential Innervation of Tissues Located at Traditional Acupuncture Points in the Rat Forehead and Face

Acupuncture in Medicine ◽

10.1136/acupmed-2017-011595 ◽

2018 ◽

Vol 36 (6) ◽

pp. 408-414 ◽

Cited By ~ 2

Author(s):

Jia Wang ◽

Jingjing Cui ◽

Chen She ◽

Dongsheng Xu ◽

Zhiyun Zhang ◽

...

Keyword(s):

Nervous System ◽

Sensory Neurons ◽

Motor Neurons ◽

Acupuncture Point ◽

Acupuncture Points ◽

Motor Nucleus ◽

Neural Pathways ◽

Trigeminal Motor Nucleus ◽

Facial Motor Nucleus ◽

Neural Tracing

Objectives To compare the neural pathways associated with the tissues located at different traditional acupuncture points in the rat forehead and face using the cholera toxin B subunit (CTB) neural tracing technique. Methods After injection of CTB into the tissues at GB14, ST2 and ST6 in the rat, the neural labelling associated with each acupuncture point was revealed by fluorescent immunohistochemistry of the nervous system, including the trigeminal ganglion (TRG), cervical dorsal root ganglia (DRG), spinal cord and brain. Results The CTB labelling included sensory neurons and their transganglionic axonal terminals, as well as motor neurons. The labelled sensory neurons associated with GB14, ST2 and ST6 were distributed in both the TRG and cervical DRG, and their centrally projected axons terminated in an orderly fashion at their corresponding targets in the spinal trigeminal nucleus and cervical spinal dorsal horn. In addition, labelled motor neurons were observed in the facial motor nucleus, trigeminal motor nucleus and cervical spinal ventral horn, in which facial motor neurons projected to the tissues located at all three acupuncture points. Trigeminal motor neurons innervated both ST2 and ST6, while spinal motor neurons only correlated with ST6. Conclusions These results indicate that the tissues located at each of these three traditional acupuncture points in the rat forehead and face has its own sensory and motor connection with the nervous system in a region-specific pattern through distinct neural pathways. Understanding the neuroanatomical characteristics of acupuncture points from the peripheral nervous system to the central nervous system should help inform acupuncture point selection according to the demands of the clinical situation.

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Afferent-Induced Changes in Rhythmic Motor Programs in the Feeding Circuitry of Aplysia

Journal of Neurophysiology ◽

10.1152/jn.00137.2004 ◽

2004 ◽

Vol 92 (4) ◽

pp. 2312-2322 ◽

Cited By ~ 15

Author(s):

Avniel N. Shetreat-Klein ◽

Elizabeth C. Cropper

Keyword(s):

Sensory Neurons ◽

Motor Neurons ◽

Rhythmic Activity ◽

Motor Program ◽

Firing Frequency ◽

Afferent Activity ◽

Motor Programs ◽

Rhythmic Motor ◽

Induced Changes ◽

The Impact

A manipulation often used to determine whether a neuron plays a role in the generation of a motor program involves injecting current into the cell during rhythmic activity to determine whether activity is modified. We perform this type of manipulation to study the impact of afferent activity on feeding-like motor programs in Aplysia. We trigger biting-like programs and manipulate sensory neurons that have been implicated in producing the changes in activity that occur when food is ingested, i.e., when bites are converted to bite-swallows. Sensory neurons that are manipulated are the radula mechanoafferent B21 and the retraction proprioceptor B51. Data suggest that both cells are peripherally activated during radula closing/retraction when food is ingested. We found that phasic subthreshold depolarization of a single sensory neuron can significantly prolong radula closing/retraction, as determined by recording both from interneurons (e.g., B64), and motor neurons (e.g., B15 and B8). Additionally, afferent activity produces a delay in the onset of the subsequent radula opening/protraction, and increases the firing frequency of motor neurons. These are the changes in activity that are seen when food is ingested. These results add to the growing data that implicate B21 and B51 in bite to bite-swallow conversions and indicate that afferent activity is important during feeding in Aplysia.

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