• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.9
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• pp.560-567
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• 2003

EMG recordings of the electrical activity of muscle have proved to be a valuable tool in studying muscle function and reflex activity. SP(silent period) is elicited by a electrical stimulation on the chin during isometric contraction of jaw muscle. This paper proposes a model of the inhibitory reflex mechanism of jaw muscle after electrical stimulation. The SPs of jaw muscle after a electrical stimulation to the chin were divided into SP1 and SP2. SP1 is produced by the activation of periodontal receptors. The activation of nociceptors contributes to the SP2. As a result, the EMG signal generated by a proposed a model of inhibitory reflex mechanism is similar to real both EMG signal including SP1 and SP2. The present study have shown differences of SP1 and SP2 induced by inhibitory reflex mechanism.

• The Journal of Korean Physical Therapy
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• v.12 no.1
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• pp.49-56
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• 2000

The purpose of this study was to investigate the influnce of afferent stimuli, transcutaneous electrical nerve stimulation and ultra sound, on the electrdiagnostic study of normal subjects. Electrodiagnostic study was performed before and after the application of afferent stimulation of the right popliteal fossa on 18 healthy female volunteers. After the transcutaneous electrical nerve stimulation, there is no significantly change of latencies and amplitudes of SEP, H-reflex, peroneal nerve F-wave, and sensory nerve conduction. After the ultra sound, there is no significantly change of latencies and amplitudes of SEP, H-reflex, peroneal nerve F-wave, and sensory nerve conduction. Tibial nope F-wave and motor nerve shows prolonged latency after TENS and US (p<0.01). Ultrasound may have a similar mechanism of action compared to transcutaneous electrical nerve stimulation by having localized inhibitory effects of the peripheral nerve. However, further investigation is needed to assess their mechanism of action and the precise relevance of stimulation modality.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.307-312
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• 1998

This study was performed to investigate the mechanism of central analgesic effects of antidepressants. Thirty four male rats were anesthetized with pentobarbital sodium (40 mg/kg, ip). A stainless steel guide cannula and a PE tube (PE10) were implanted into the lateral ventricle and cisterna magna area. Stimulating and recording electrodes were implanted into the incisor pulp and anterior digastric muscle. Electrodes were led subcutaneously to the miniature cranial connector sealed on the top of the skull with acrylic resin. The jaw opening reflex was used in freely moving rats, and antidepressants were administered intracisternally in order to eliminate the effects of anesthetic agents on the pain assessment and evaluate the importance of the central action site of antidepressants. After 48 hours of recovery from surgery, digastric electromyogram (dEMG) of freely moving rats was recorded. Electrical shocks (200 ${\mu}sec$ duration, 0.5-2 mA intensity) were delivered at 0.5 Hz to the dental pulp every 2 minute. Intracisternal administration of $15\;{\mu}g$ imipramine suppressed dEMG elicited by noxious electrical stimulation in the tooth pulp to $76{\pm}6%$ control. Intracisternal administration of $30\;{\mu}g$ desipramine, nortriptyline, or imipramine suppressed dEMG remarkably to $48{\pm}2,\;27{\pm}8,\;or\;25{\pm}5%$ of the control, respectively. Naloxone, methysergide, and phentolamine blocked the suppression of dEMG produced by intracisternal antidepressants from $23{\pm}2\;to\;69{\pm}4%,\;from\;32{\pm}5\;to\;80{\pm}9%,\;and\;from\;24{\pm}6\;to\;77{\pm}5%$ of the control, respectively. These results indicate that antidepressants produce antinociception through central mechanisms in the orofacial area. Antinociception of intracisternal antidepressants seems to be mediated by an augmentation of descending pain inhibitory influences on nociceptive pathways.

• International Neurourology Journal
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• v.22 no.4
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• pp.252-259
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• 2018

Purpose: Naftopidil ((${\pm}$)-1-[4-(2-methoxyphenyl) piperazinyl]-3-(1-naphthyloxy) propan-2-ol) is prescribed in several Asian countries for lower urinary tract symptoms suggestive of benign prostatic hyperplasia. Previous animal experiments showed that intrathecal injection of naftopidil abolished rhythmic bladder contraction in vivo. Naftopidil facilitated spontaneous inhibitory postsynaptic currents in substantia gelatinosa (SG) neurons in spinal cord slices. These results suggest that naftopidil may suppress the micturition reflex at the spinal cord level. However, the effect of naftopidil on evoked excitatory postsynaptic currents (EPSCs) in SG neurons remains to be elucidated. Methods: Male Sprague-Dawley rats at 6 to 8 weeks old were used. Whole-cell patch-clamp recordings were made using SG neurons in spinal cord slices isolated from adult rats. Evoked EPSCs were analyzed in $A{\delta}$ or C fibers. Naftopidil or prazosin, an ${\alpha}1$-adrenoceptor blocker, was perfused at $100{\mu}M$ or $10{\mu}M$, respectively. Results: Bath-applied $100{\mu}M$ naftopidil significantly decreased the peak amplitudes of $A{\delta}$ and C fiber-evoked EPSCs to $72.0%{\pm}7.1%$ (n=15) and $70.0%{\pm}5.5%$ (n=20), respectively, in a reversible and reproducible manner. Bath application of $100{\mu}M$ prazosin did not inhibit $A{\delta}$ or C fiber-evoked EPSCs. Conclusions: The present study suggests that a high concentration of naftopidil reduces the amplitude of evoked EPSCs via a mechanism that apparently does not involve ${\alpha}1$-adrenoceptors. Inhibition of evoked EPSCs may also contribute to suppression of the micturition reflex, together with nociceptive stimulation.

• PNF and Movement
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• v.5 no.1
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• pp.29-35
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• 2007

Purpose : The purpose of this study was investigated to find the approach in the PNF and TC for frail elder Method : This is a literature study with books, articles, seminal note and books for PNF and TC international course. Result : Neural mechanisms contribute significantly to the gains that occur in the range of motion about a joint with stretching exercises. The participation in a stretch-training program decreases tonic reflex activity and increases flexibility and decreases in force production and muscle activation. Also the stretching-induced decreases may be due to a central nervous system inhibitory mechanism. PNF stretch techniques can increase ROM in older adults. These results may differ from those of studies performed with younger populations because of age-related physiologic changes. TC exercise improves balance control and muscle strength and were associated with reorganized lower extremity neuromuscular patterns. Conclusions : The stretch training program of the PNF and TC contribute to increase the balance and coordination for frail elder. Therefore, The frail elder prevent falling. Further study, The PNF and TC be introduced as the new therapeutic intervention for frail elder.

• The Korean Journal of Physiology
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• v.8 no.2
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• pp.1-17
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• 1974

This experiment was designed to explore the specific functional interrelations between the vestibular semicircular canals and the extraocular muscles which may disclose the neural organization, connecting the vestibular canals and each ocular motor nuclei in the brain system, for vestibuloocular reflex mechanism. In urethane anesthetized rabbits, a fine wire insulated except the cut cross section of its tip was inserted into the canals closely to the ampullary receptor organs through the minute holes provided on the osseous canal wall for monopolar stimulation of each canal nerve. All extraocular muscles of both eyes were ligated and cut at their insertio, and the isometric tension and EMG responses of the extraocular muscles to the vestibular canal nerve stimulation were recorded by means of a physiographic recorder. Upon stimulation of the semicircular canal nerve, direction if the eye movement was also observed. The experimental results were as follows. 1) Single canal nerve stimulation with high frequency square waves (240 cps, 0. 1 msec) caused excitation of three extraocular muscles and inhibition of remaining three muscles in the bilateral eyes; stimulation of any canal nerve of a unilateral labyrinth caused excitation (contraction) of the superior rectus, superior oblique and medial rectus muscles and inhibition (relaxation) of the inferior rectus, inferior oblique and lateral rectos muscles in the ipsilateral eye, and it caused the opposite events in the contralateral eye. 2) By the overlapped stimulation of triple canal nerves of a unilateral labyrinth, unidirectional (excitatory or inhibitory) summation of the individual canal effects on a given extraocular muscles was demonstrated, and this indicates that three different canals of a unilateral vestibular system exert similar effect on a given extraocular muscles. 3) Based on the above experimental evidences, a simple rule by which one can define the vestibular excitatory and inhibitory input sources to all the extraocular muscles is proposed; the superior rectus, superior oblique and medial rectus muscles receive excitatory impulses from the ipsilateral vestibular canals, and the inferior rectus, inferior oblique and lateral rectus muscles from the contralateral canals; the opposite relationship applies for vestibular inhibitory impulses to the extraocular muscles. 4) According to the specific direction of the eye movements induced by the individual canal nerve stimulation, an extraocutar muscle exerting major role (a muscle of primary contraction) and two muscles of synergistic contraction could be differentiated in both eyes. 5) When these experimental results were compared to the well known observations of Cohen et al. (1964) made in the cats, extraocular muscles of primary contraction were the same but those of synergistic contraction were partially different. Moreover, the oblique muscle responses to each canal nerve excitation appeared to be all identical. However, the responnes of horizontal (medial and lateral) and vertical (superior and inferior) rectus muscles showed considerable differences. By critical analysis of these data, the author was able to locate theoretical contradictions in the observations of Cohen et al. but not in the author's results. 6) An attempt was also made to compare the functional observation of this experiment to the morphological findings of Carpenter and his associates obtained by degeneration experiments in the monkeys, and it was able to find some significant coincidence between there two works of different approach. In summary, the author has demonstrated that the well known observations of Cohen et al. on the vestibulo-ocular interrelation contain important experimental errors which can he proved by theoretical evaluation and substantiated by a series of experiments. Based on such experimental evidences, a new rule is proposed to define the interrelation between the vestibular canals and the extraocular muscles.