• The Korean Journal of Pain
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• v.9 no.2
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• pp.326-335
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• 1996

Background: Though a number of studies have described the distribution of substance P(SP)-like immunoreactivity in the spinal cord, they have been focused on lamina I and II of the dorsal horn and there are little morphological studies on the topographic distribution and ultrastructure of the SP immunoreactive neurons especially in the ventral horn of the spinal cord. this study was conducted to identify distribution pattern of SP immunoreactive neurons and to difine the synaptic organization of their processes in ventral horn of the thoracic cord of the cat by preembbeding immunocytochemical method using SP antiserum. Methods: Five adults cats of either sex were used and deeply anesthetized by intramuscular injection of ketamine. After removal of the spinal cord, samples of thoracic cord were taken and placed in fresh fixative at $4^{\circ}C$ for 2 hours. Transverse sections $50{\mu}m$ thick were processed using the preembbeding immunocytochemical method and incubated consecutively in the specific primary antibody and the 10% normal goat serum, the rabbit anti-substance P antiserum, the biotin-labelled goat anti-rabbit IgG and finally the avidin-biotin-peroxidase complex. The processed tissue sections were throughly washed and stained in the black with 1% uranyl acetate. Section were examined on a electron microscope. Results: 1) SP immunoreactive neurons were observed in the gray matter around central canal. 2) In lamina I and II SP immunoreactivity was observed in both myelinated and unmyelinated nerve fibers, but in ventral horn only in the unmyelinated nerve fibers. 3) SP immunoreactive axon terminals with small round and large dense core vesicles made chemical synapses onto the dendrites of motor neurons in the ventral horn. Conclusion: SP immunoreactive neurons might play an important role in modulation of motor neurons in the ventral horn of the thoracic cord of the cat.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.177-185
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• 2001

This study has been carried out to determine localization of Manduca sexta allatotropin (Mas-AT) neuropeptide in developing ventral nerve cord of the silk moth Bombyx mori with polyclonal antisera against Mas-AT. Suboesophageal ganglion (SOG) of the second to fifth instar larvae and 3-day-old pupae showed two to ten Mas-AT-immunoreactive (Mas-AT-IR) cell bodies. There were two to three pairs of labeled cell bodies in each thoracic ganglion (TG) from third instar larvae to adults, with the exception of TG from prepupae. One pair of labeled cell bodies was localized in each abdominal ganglion (AG) 1 to 6 from third instar larvae to 3-day-old pupae, whereas in 5-day-old pupae to adults there was one pair in a similar location of AG 1 to 5. The seventh neuromeres of terminal abdominal ganglia (TAG) from third instar Iarvae to 3- day-old pupae contained four labeled large cell bodies. In each of AG 1 to 7, these cell bodies showed similar allatotropin-immunoreactivity in appearance. Some labeled axons, projected from Mas-AT-lR cells in each of those AG, were extended to the nerves N 1 and N 2.

• The Korean Journal of Physiology
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• v.21 no.1
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• pp.59-66
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• 1987

This study was aimed to investigate whether the conduction velocity of nerve impulses through the ventral afferent fibers is constant along their entire courses in dorsal as well as in ventral roots. Cats were anesthetized with ${\alpha}-chloralose$ (60 mg/kg, i.p.) and artificially ventilated. Laminectomies were done on L4-S1 spinal vertebrae to expose the lumbosacral spiral cord. Both ventral and dorsal roots of L7 or S1 spinal segments were isolated and cut near the spinal cord. Ventral roots were placed on 6-lead stimulating electrodes and stimulated with supra C-threshold intensity. Divided dorsal root fascicles were placed on bipolar recording electrodes and single fiber units activated by the stimulation of the ventral roots were identified. Followings are the results obtained: 1) A total of 27 VRA units were identified. 10 units of them conducted impulses slower than 2 m/sec. Conduction velocities of the remaining units were in the range of 3.11-20.91 m/sec. 2) In 12 Units conduction velocities Of the VRA units through dorsal$(CV_{DR})$ and venral root$(CV_{DR})$ were determined respectively. There was a tendency to conduct impulses faster through dorsal roots$(CV_{DR}=8.19{\pm}3.26\;m/sec)$ than ventral roots$(CV_{DR}=3.46{\pm}1.02\;m/sec)$. From the above results we confirmed that there exist nerve fibers in continuity between the spinal ventral and dorsal roots but we could not ascertain whether there is a change in conduction velocity through the entire course of ventral afferent unit.

• The Journal of Korean Physical Therapy
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• v.19 no.2
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• pp.41-55
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• 2007

Purpose: This study aimed to compare the effect on nerve regeneration of ultrasound irradiation in rats with peripheral nerve injury. Methods: To investigate alterations of the NCAM immunoreactivity in non-crushed part and crushed part of the spinal cord, the unilateral sciatic nerve of the rats were crushed. The expression of NCAM was used as the marked of peripheral nerve regeneration, and also plays an important role in developing nerve system. Experimental animals were sacrificed by perfusion fixation at post-injury 1, 3, 7, 14 days after ultrasound irradiation. The pulsed US was applied at a frequency of 1MHz and a spatial average-temporal average Intensity of 0.5W/of (20% pulse ratio) for 1 mins. The Luxol fast blue-cresyl violet stain were also done to observe the morphological changes. Results: Alteration of NCAM immunoreactivity in the crushed part and the non-crushed part of lower lumbar spinal cord were observed. NCAM-immunoreactivity cells were some increased in the dorsal horn lamina I, III and cell ventral horn at 1 day after unilateral sciatic nerve injury. However, there was not significant difference in the relationship between crushed part and non-crushed part. NCAM-inmmunoreactivity was remarkably increased at 3 days after unilateral sciatic nerve injuryin the gray matter and white matter. NCAM-immunoreactivity was increased in the ventral horn and post horn of experimental crushed part. Also, NCAM-immunoreactivity in large motor neurons in ventral horns lamina VIII, IX were increased at 7 days after unilateral sciatic nerve injury. At 14 days after sciatic nerve crushed injury, there was no significant difference. All group were decreased for 14 days. In the time course of NCAM expression, all groups showed a significant difference at 3day groups(p<0.05). Whereas, CC group was noted a significant difference between 3day and 7 day group respectively. In NCAM expression, there were significantly increased in all group. In the relationship between CNC group and ENC group, significant difference was detected among 3, 7, 14 day group(p<0.05). The difference between CC group and ENC group were noted in all groups(p<0.05). Conclusion: It is consequently suggested that the effects of the ultrasound irradiation may increase the NCAM immunoreactive neurons and glial cell in the spinal cord after unilateral sciatic nerve crushed injury. Therefore, the increased NCAM immunoreactivity in the spinal cord may reflect the neuronal damage and healing process induced by a ultrasound irradiation after peripheral nerve injury in rat.

• Journal of Acupuncture Research
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• v.28 no.3
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• pp.33-42
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• 2011

Objectives : This study was performed to evaluate the effects of Scutellariae radix (SR) water extract on locomotor dysfunction induced by spinal cord injury (SCI) in rats. Methods : SCI was induced mechanical contusion following laminectomy of 10 th thoracic vertebra in Sprague-Dawley rats. SR was orally given once a day for 7 days after SCI. Neurological behavior was examined with the Basso-Beattie-Bresnahan locomotor rating scale. Tissue damage and nerve fiber degeneration were examined with cresyl violet and luxol fast blue (LFB) histochemistry. Using immunohistochemistry, cellular damages to neurons and nerve fibers were examined MAP-2. Results : 1. SR significantly ameliorated the locomotor dysfunction of the SCI-induced rats. 2. SR significantly reduced the number of motor neurons in the ventral horn of the SCI-induced rat spinal cord. 3. SR attenuated the reduction of nerve fiber shirnakage and degeneration of the SCI-induced rat spinal cord. 4. SR attenuated the reduction of MAP-2 positive cells in the peri-lesion of the SCI-induced rat spinal cord. Conclusions : These results suggest that SR improves the locomotor dysfunction of SCI by reducing degeneration of nerve fibers and motor neuron shrinkage in the ventral horn.

• The Journal of Korean Physical Therapy
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• v.23 no.2
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• pp.45-52
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• 2011

Purpose: The purpose of this study was to investigate the effect of electroacupuncture on NeuN expression in ventral horn motor neurons of spinal cord, changes in pain thresholdchanges in motor function in rats with partially dissected sciatic nerves. Method: A total of 120 male Sprague-Dawley rats were randomly divided into two groups, a control group and a group administered electroacupuncture at ST36, LI11 and SP9 with 120 Hz and 0.5 mA. Animals were sacrificed on days 1, 3, 7, 14 and 28 after nerve injury (the sciatic nerve was partially dissected). The pain threshold was recorded by an Analgesia? meter and a BBB? score was calculated for motor function. After preparing lumbar spinal cord slide sections, they were immunostained with NeuN antisera (1:2,500). Results: The numbers of NeuN immunoreactive neuronsin the electroacupuncture group was increased compared to the control group. The numbers of NeuN immunoreactive neurons on days 14 and 28 day were different (p<0.05), as were the numbers on days 3 and 7 (p<0.01). The pain threshold BBB score for the electroacupuncture group was higher than for controls. Conclusion: The increase in pain threshold, BBB-score and number of NeuN immunoreactive neurons inventral horn motor neurons of spinal cord in rats withnerve dissection showed that electroacupuncture can attenuate pain transduction and increase motor function. Also, NeuN was a good marker for identifying the degree of nerve cell loss after nervous system injury.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.2
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• pp.1-15
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• 2010

Objectives : This study was performed to evaluate the effects of root of Cibotii rhizoma(CR) ethanol extract on the tissue and neuronal damage of the spinal cord injury(SCI). Methods : SCI was induced by mechanical contusion following laminectomy of 10th thoracic vertebra in Sprague-Dawley rats. CR was orally given once a day for 7 days after SCI. Tissue damage and nerve fiber degeneration were examined with cresyl violet and luxol fast blue(LFS) histochemistry. HSP72(as neuronal damage marker), MAP2(as nerve fiber degeneration marker), c-Fos(immediate early gene), and Bax(pro-apoptotic molecule) expressions were examined using immuno-histochemistry. Individual immuno-positive cells expressing HSP72, MAP2, c-Fos and Bax were observed on the damaged level and the upper thoracic and lower lumbar spinal segments. Results : 1. CR reduced degeneration of nerve fibers and motor neuron shrinkage in the ventral horn of the lower lumbar spinal segment, but generally it did not seem to ameliorate the tissue injury following SCI. 2. CR reduced demyelination in the ventral and lateral funiculus of the lower lumbar spinal segment. 3. CR reduced HSP72 expression on the neurons in the peri-central canal gray matter adjacent to the damaged region. 4. CR strengthened MAP2 expression on the motor neurons in the ventral horn and on nerve fibers in the lateral funiculus of the lower lumbar spinal segment. 5. CR reduced c-Fos positive cells in the peri-lesion and the dorsal horn of the damaged level and in the ventral horn of the lower lumbar spinal segment. 6. CR reduced Bax positive cells in the peri-lesion and the dorsal horn of the damaged level and in the ventral horn of the lower lumbar spinal segment. Conclusions : These results suggest that CR plays an inhibitory role against secondary neuronal damage and nerve fiber degeneration. following SCI.

• The Korean Journal of Physiology
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• v.24 no.2
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• pp.389-402
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• 1990

The physiological characteristics of the neurons receiving the ventral root afferent inputs were investigated in the cat. A total of 70 cells were identified in the lumbosacral spinal cord. All these cells responded only to the C-strength stimulation of the distal stump of cut ventral root and the estimated conduction velocities of the VRA fibers were not faster than 4 m/sec. The majority of them were silent in resting state. For 49 cells, their peripheral receptive fields were characterized. Among them, 25 cells were exclusively excited by VRA inputs, 8 were inhibited and the remaining cells recevied both excitatory and inhibitory VRA inputs. According to the response pattern to the mechanical stimuli applied to their receptive fields, only a fourth of them were typical high threshold cell, a sixth, wide dynamic range cells, while remainings were a rather complex cells. Most of the cells receiving VRA inputs, received only the A ${\delta}-peripheral$ nerve inputs. Intravenous injection of morphine decreased the response of spinal cells to the VRA activation. The responses were abolished completely by counter irritation to the common peroneal nerve with C-strength-low frequency stimuli. These physiological properties of the spinal neurons receiving the VRA inputs are differ in some aspect from the spinal neurons receiving nociceptive inputs from the periphery, but still were consistent with the contention that VRA system might carry nociceptive informations arising from the spinal cord and/or neraby surrounding tissues.

• Biomedical Science Letters
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• v.27 no.4
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• pp.239-247
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• 2021

The scuttle fly is a fly species in the Phoridae family. Scuttle fly which moves abruptly after standing for a while and stop suddenly to rush off again. These characteristic behaviors of the scuttle fly seem to be related to muscular and nervous system or neurotransmitters. Thus, we focused at the neurotransmitter, corazonin (Crz) that is known to be related to resistance to stress and investigated the developmental process of the neurons in the scuttle fly. In a previous studies, we found that there are three groups of corazoninergic neurons in the larval CNS of the scuttle. Larva has 3 pairs of Crz neurons at the dorsolateral area of the brain, 1 pair at the dorsomedial brain and 8 pairs at the ventral nerve cord. In this studies, among these neurons, 1 pair of dorsomedial brain and 8 pairs of ventral nerve cord disappear in early pupal stage after metamorphosis. Only the 3 pairs of dorsolateral brain persist expression of Crz gene through all the period of pupa stage. This group of neurons converge gradually to frontal center of the brain and situated at the medial region. These pairs of corazoninergic neurons keep their number and location in adult stage. In the future, we expect further studies on the histological characteristics of corazonin-expressing cells and the expression of corazonin gene.

• Applied Microscopy
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• v.43 no.2
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• pp.65-74
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• 2013

Although the geometrical difference in body position between web-building and wandering spiders could affect the organization of their central nervous system (CNS), however most of our informations about spider's CNS are dependent on those revealed from the wandering spiders. Therefore, this paper describes microstructural organizations of the CNS in the geometric orb-web spider Araneus ventricosus. Similarly to other wandering spiders, the CNS of A. ventricosus is also consisted of a dorsal supraesophageal ganglion and a ventral subesophageal mass. The supraesophageal ganglia are fused together and made up of a large sized nerve cell clusters, whereas the subesophageal ganglia are made up of the foremost part of the ventral nerve cord. It has been revealed that the only nerve arising from the supraesophageal mass was the optic nerve which connected with four pairs of eyes, whereas a pair of pedipalpal and four pairs of appendage nerves including abdominal nerve pairs were arisen from the subesophageal nerve mass. Fibrous masses are highly organized into longitudinal and transverse tracts, and are only consisted of processes of neurons and the terminal ramnifications of peripheral sensory neurons. In addition, central fibrous mass of both the brain and the subesophageal mass are totally devoid of nerve cell bodies.