• Applied Microscopy
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• v.25 no.1
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• pp.48-64
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• 1995

Ultrastructure of nerves and their associated cells in the bronchiolar epithelium of the human fetal lung were studied with ultrastructural and immunohistochemical methods. The neuroendocrine cells were scattered along the basal part of non-ciliated respiratory epithelium and appeared as single cell (solitary neuroendocrine cell) or groups (neuroepithelial bodies). The solitary neuroendocrine cells were devoid of any detectable innervation, while the neuroepithelial bodies were associated with nerve ending containing morphologically afferent (sensory) and efferent (motor) intraepithelial terminals. The afferent nerve endings contained abundant mitochondria with long cristae. The efferent nerve endings were characterized by the presence of synaptic vesicles. Both types of nerve endings formed synaptic junction between nerve endings and neuroepithelial bodies cells. Serial sections of the intraepithelial nerves revealed that both morphologically afferent and efferent types of nerve endings may be formed by the same nerve fiber. By immunohistochemistry, bombesin and serotonin were localized in solitary neuroendocrine cells and neuroepithelial bodies of human fetal lung from various prenatal age groups. These results suggest that the neuroepithelial bodies cells of the human fetal lung have neuroreceptor function.

• Journal of Korean Biological Nursing Science
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• v.8 no.1
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• pp.39-48
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• 2006

Purpose: To see the effects of capsaicin on the peripheral nerve damage of intervibrissal fur in mature rats, Method: 24 female mature rats($200{\sim}250g$) are divided to 3 groups and compared with each other. Immunofluorescence dye using CGRP and PGP antibodies was performed and 8 weeks after administration of capsaicin with control group. Result: The immunopositive reaction against PGP and CGRP was reduced by the damage of epidermal and dermal endings in unmyelinated sheath and thin myelinated sheath and the group after 8weeks showed distinct positive reaction of PGP and CGRP than the group after 4 weeks which means the recover of nerves. Conclusion: As a result, capsaicin influenced on pain-related neurotransmitter like CGRP when administerd to mature rats and even though it caused the damages on unmyelinated sheath and thin myelinated sheath, the damaged nerves recovered after 8 weeks. Also the research about sensory nerve endings scattered over middle dermal and deep epidermal layers such as lanceolate, merkel reticular, Ruffini endings should be studied when the research of the inner conical body is performed. Further studies are necessary about the toxicity and effect of capsaicin on the peripheral nerve endings.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.2
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• pp.145-152
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• 2017

Remote ischemic preconditioning (RIPC) is an intrinsic phenomenon whereby 3~4 consecutive ischemia-reperfusion cycles to a remote tissue (non-cardiac) increases the tolerance of the myocardium to sustained ischemia-reperfusion induced injury. Remote ischemic preconditioning induces the local release of chemical mediators which activate the sensory nerve endings to convey signals to the brain. The latter consequently stimulates the efferent nerve endings innervating the myocardium to induce cardioprotection. Indeed, RIPC-induced cardioprotective effects are reliant on the presence of intact neuronal pathways, which has been confirmed using nerve resection of nerves including femoral nerve, vagus nerve, and sciatic nerve. The involvement of neurogenic signaling has been further substantiated using various pharmacological modulators including hexamethonium and trimetaphan. The present review focuses on the potential involvement of neurogenic pathways in mediating remote ischemic preconditioning-induced cardioprotection.

• The Journal of Korean Physical Therapy
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• v.15 no.2
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• pp.12-18
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• 2003

Proprioception can be defined as a specialized variation of touch that encompasses the sensation of joint movement(kinesthesia) and joint position(static joint position sense). Several types of joint and muscular mechanoreceptors provide proprioceptive information for joint stability. Joint mechanoreceptors have been classified into four types based of activation characteristics : Ruffini endings, Pacinian corpuscles, Golgi tendon organlike endings, free nerve endings. The paper review the morphology, distrubution, function of mechanoreceptors in shoulder joint.

• Journal of Korean Orthopaedic Sports Medicine
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• v.4 no.1
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• pp.29-35
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• 2005

Purpose: The anterior cruciate ligament(ACL) has a neuromuscular control function as evidenced by the presence within it of mechanoreceptor. Although these mechanoreceptors have been identified, the afferent somatosensory pathways from ACL to the cerebrum have yet to be demonstrated in their entirety. In order to trace these afferent pathway, we conducted a viral trans-synaptic tracing experiment using the neurotropic pseudorabies virus(PRV). Material and Methods: The PRV was injected into the ACL of rats and allowed to replicate and spread trans-synaptically for 6 to 7 days. The brain and spinal cord of each sacrificed rat was then removed and processed immunohistochemically to detect the presence of PRV. Results: PRV-immunoreactive neurons were found to be localized in several different regions from the spinal cord to the cerebrum. Four nuclei in the reticular formation of the brain stem demonstrated strong positive labeling: the mesencephalic reticular nucleus, magnocelluar reticular nucleus, paragigantocellular reticular nucleus, and gigantocellular reticular nucleus. Conclusions: This findings suggests that the nerve endings of the rat ACL project into the cerebrum and that the reticular formation may play an important role in the afferent pathway of those nerve endings.

• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.439-455
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• 1994

The purpose of this study was to investigate the distribution of nerves in the periodontal ligament of a dog's primary teeth by each developing stage. The distribution of nerves in the periodontal ligament were investigated by means of immunohistochemistry for detection of neurofilament protein (NFP). The results were as follows: The NFP-immunoreactive nerve fibers were found to be densely distributed in the apical third of the periodontal ligament, while they were sparse in the coronal two third, in both primary and permanent teeth. In generally the density of distribution and degree of arborization of nerve fibers in periodontal ligament of primary teeth revealed a poor appearance compared with that of permanent teeth. Periodontal ligament in anterior teeth showed more abundant nerve innervation than posterior teeth, and the periodontal ligament of the bifurcation area in posterior teeth roots were not observed to have nerve fiber. The density of nerve distribution in the periodontal ligament of primary teeth was reduced according to the physiological root resorption and nerve fibers were not observed in the surrounding area on the root of the exfoliation stage in primary teeth. The distribution of nerve fibers in mucogingival tissue, was poor innervated according to the aging of the dogs. A more abundant distribution of nerve fiber was represented in the lingual mucogingival tissue than in the labial side. Most of the nerve endings in the periodontal ligament of primary teeth showed a tree-like appearance. However, the typical Ruffini-like nerve endings were not observed.

• Applied Microscopy
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• v.22 no.1
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• pp.1-14
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• 1992

Parenchyma of the cat pineal body consisted of pinealocytes and glial cells. The pinealocyte, predominant cell type, was characterized by having large mitochondria with pale matrix, abundant polyribosomes, moderately-developed Golgi apparatus, centrioles and occasional cilia. The pinealocyte had one thick and long cytoplasmic process at the one pole of the cell, and slender and shorter processes at the other pole, and in addition occasional short processes from the cell body. These processes contained longitudinally arranged microtubules, and a few mitochondria. Thick processes teminated as bulgings either in the intercellular process-rich area, or in the perivascular border which was formed by glial cell processes. These endings of pinealocyte processes had many small vesicles, mitochondria, and occasional dense bodies. Glial cells with abundant filaments of intermediate type and clear cytoplasmic matrix were fibrous astrocyte. Perikarya of the astrocytes had small and dense mitochondria, moderately developed Golgi apparatus, dense bodies and variable amount of intermediate filaments. Glial cell processes run through the intercellular spaces among the pinealocyte processes. Glial cell of protoplasmic type had no or a few filaments, but it had well-organized rough endoplasmic reticulum, dense mitochondria, well developed Golgi apparatus and many dense granules. Intercellular canaliculi formed by adjacent pinealocytes and glial cell processes were often noted. Within the parenchyma, sympathetic and parasympathetic axons and their endings were noted. These endings were present mostly in the intercellular spaces without having membrane specialization, however, in rare instances, ending with small clear and dense cored vesicles, and large dense cored vesicles formed specialized synapse with a pinealocyte process. Within the perivascular spaces nerve fibers and endings, Schwann cells and pericyte were noted. In rare case pinealocyte process penetrated into the perivascular space through the interuptions of glial border. These results suggest that pinealocyte of the cat has less significance in secretory function and is rather neural type of cell.

• Imaging Science in Dentistry
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• v.45 no.1
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• pp.61-65
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• 2015

The mental foramen is a bilateral opening in the vestibular portion of the mandible through which nerve endings, such as the mental nerve, emerge. In general, the mental foramen is located between the lower premolars. This region is a common area for the placement of dental implants. It is very important to identify anatomical variations in presurgical imaging exams since damage to neurovascular bundles may have a direct influence on treatment success. In the hemimandible, the mental foramen normally appears as a single structure, but there are some rare reports on the presence and number of anatomical variations; these variations may include accessory foramina. The present report describes the presence of accessory mental foramina in the right mandible, as detected by cone-beam computed tomography before dental implant placement.

• The Korean Journal of Zoology
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• v.39 no.2
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• pp.223-230
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• 1996

Fine structure of the neuromuscular junction in the venomous organ of the spider, Agelena li'mbutq, was studied using high magnification electron microscope. The motor nerve endings at neuromuscular contact area composed of neurons and neuroslial cells were located between musculature and extracellular sheath of the venom gBand. At the synaptic contact between a motor axon and a muscle fiber in the musculature, spherical synaptic vesicles were prominent in the nerve terminal. The sarcoplasm beneath the neuromuscular synapse has a granular appearance and lacks mvofilaments. And the main axon gives off a branch between the muscle fibers. The synaptic regions of this organ are located close to the myofilaments unlike to other chelicerate classes. Moreover the postsvnaptic complex of vesicles and membrane invasinations present in other synaptic legions are absent from these legions in this venomous organ.

• The Korean Journal of Pain
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• v.9 no.1
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• pp.26-38
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• 1996

In a normal state, sympathetic efferent activity does not elicit discharges of sensory neurons, whereas it becomes associated with and excites sensory neurons in a pathophysiological state such as injury to a peripheral nerve. Although this sympathetic-sensory interaction is reportedly adrenergic, involved subtypes of adrenoreceptors are not yet clearly revealed. The purpose of this study was to determine which adrenorceptor subtypes were involved in sympathetic-sensory interaction that was developed in rats with an experimental peripheral neuropathy. Using rats that received a tight ligation of one or two of L4-L6 spinal nerves 10~15 days previously, a recording was made from afferent fibers in microfilaments teased from the dorsal root that was in continuity with the ligated spinal nerve. Electrical stimulation of sympathetic preganglionic fibers in T13 or L1 ventral root (50 Hz, 2-5 mA. 0.5 ms pulse duration, 10 sec) was made to see if the activity of recorded afferents was modulated. About half of afferents showing spontaneous discharges responded to sympathetic stimulation, and had the conduction velocities in the A-fiber range. Most of the sympathetically induced afferent responses were excitation. This sympathetically induced excitation occurred in the dorsal root ganglion (DRG), and was blocked by yohimbine (${\alpha}_2$ blocker), neither by propranolol ($\beta$ blocker) not by prazosine (${\alpha}_1$ blocker). The results suggest that after spinal nerve ligation, sympathetic efferents interact with sensory neurons having A-fiber axons in DRG where adrenaline released from sympathetic nerve endings excites the activity of sensory neurons by acting on 2-adrenoreceptors. This 2-adrenoreceptor mediated excitation of sensory neurons may account for sympathetic involvement in neuropathic pain.