• Title/Summary/Keyword: (peripheral) Nerve injury

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Painful Channels in Sensory Neurons

  • Lee, Yunjong;Lee, Chang-Hun;Oh, Uhtaek
    • Molecules and Cells
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    • v.20 no.3
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    • pp.315-324
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    • 2005
  • Pain is an unpleasant sensation experienced when tissues are damaged. Thus, pain sensation in some way protects body from imminent threat or injury. Peripheral sensory nerves innervated to peripheral tissues initially respond to multiple forms of noxious or strong stimuli, such as heat, mechanical and chemical stimuli. In response to these stimuli, electrical signals for conducting the nociceptive neural signals through axons are generated. These action potentials are then conveyed to specific areas in the spinal cord and in the brain. Sensory afferent fibers are heterogeneous in many aspects. For example, sensory nerves are classified as $A{\alpha}$, $-{\beta}$, $-{\delta}$ and C-fibers according to their diameter and degree of myelination. It is widely accepted that small sensory fibers tend to respond to vigorous or noxious stimuli and related to nociception. Thus these fibers are specifically called nociceptors. Most of nociceptors respond to noxious mechanical stimuli and heat. In addition, these sensory fibers also respond to chemical stimuli [Davis et al. (1993)] such as capsaicin. Thus, nociceptors are considered polymodal. Recent advance in research on ion channels in sensory neurons reveals molecular mechanisms underlying how various types of stimuli can be transduced to neural signals transmitted to the brain for pain perception. In particular, electrophysiological studies on ion channels characterize biophysical properties of ion channels in sensory neurons. Furthermore, molecular biology leads to identification of genetic structures as well as molecular properties of ion channels in sensory neurons. These ion channels are expressed in axon terminals as well as in cell soma. When these channels are activated, inward currents or outward currents are generated, which will lead to depolarization or hyperpolarization of the membrane causing increased or decreased excitability of sensory neurons. In order to depolarize the membrane of nerve terminals, either inward currents should be generated or outward currents should be inhibited. So far, many cationic channels that are responsible for the excitation of sensory neurons are introduced recently. Activation of these channels in sensory neurons is evidently critical to the generation of nociceptive signals. The main channels responsible for inward membrane currents in nociceptors are voltage-activated sodium and calcium channels, while outward current is carried mainly by potassium ions. In addition, activation of non-selective cation channels is also responsible for the excitation of sensory neurons. Thus, excitability of neurons can be controlled by regulating expression or by modulating activity of these channels.

Analgesic Effects of Sokyungwhalhyul-tang on Constriction Nerve Injury-Induced Neuropathic Pain in Rats (말초 신경병증성 통증 모델에서 소경활혈탕의 진통 효과)

  • Kim, Kyung-Yoon;Jeong, Hyun-Woo;Choi, Chan-Hun;Kim, Hyung-Woo;Kim, Gi-Do;Sim, Ki-Cheol;Kim, Gye-Yeop
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.2
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    • pp.195-201
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    • 2011
  • Nardostachys chinensis;Anti-proliferation;Cell cycle arrest;Differentiation;U937 cells; This study was conducted to determine the analgesic effect of Sokyungwhalhyul-tang(SKWHT) using the model of peripheral neuropathic pain model. A model of neuropathic pain was made by ligating left 5th lumbar spinal nerve of rats. After 1 days, the extract of SKWHT was orally administered daily. Rats were divided into four groups; (1) Control group(n=6), (2) Experimental group I(SKWHT-OA1, 100 mg/kg, n=6), (3) Experimental group II(SKWHT-OA2, 300 mg/kg, n=6), (4) Experimental group III(SKWHT-OA3, 500 mg/kg, n=6). After that, we examined the withdrawl response of neuropathic rats legs by von Frey filament and Hot plate at pre, $1^{th}$, $4^{th}$, $7^{th}$, $14^{th}$, $21^{th}$ days after the induction of neuropathic pain. And also we examined c-fos, GOT, GPT and histological study of Liver at 21th days. von Frey filament and Hot plate were increase in experimental group I, II, III than Con. especially group III was most significantly analgesic effect than the other groups at $14^{th}$, $21^{th}$ days. In c-fos protein expression on spinal cord, group III was most significantly reduction immunoreactivity at $21^{th}$ days and in blood serum GOT & GPT levels and histologic finding of Liver in all experimental groups were no significant difference with Con at $21^{th}$ days. According to the above results, SKWHT(500 mg/kg) may have a significant analgesic effect on the neuropathic pain.

Clinical Characteristics of Patients Treated in an Emergency Center for Vascular Trauma (일개 응급센터에 내원한 외상성 혈관손상 환자의 임상적 특성)

  • Park, Yong Myeon;Yeom, Seok Ran;Jeong, Jin Woo;Han, Sang Kyun;Jo, Suck Ju;Ryu, Ji Ho;Kim, Yong In;Chung, Sung Woon
    • Journal of Trauma and Injury
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    • v.22 no.1
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    • pp.5-11
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    • 2009
  • Purpose: The mortality and the amputation rates due to vascular trauma remain high despite advanced vascular surgical techniques and supportive management. The clinical features of patients with vascular trauma have not been well studied in the Korean population. The aim of this study was to analyze the clinical characteristics of patients with vascular trauma and to develop a database and guidelines for improving the outcomes of treatment. Methods: The medical records of 37 patients with traumatic vascular injuries who had visited in an emergency center between January 2002 and December 2006 were retrospectively reviewed and statistically analyzed. Results: The mean age was 37.8 years, and the male-to-female ratio was 5.2 : 1. The mechanism of vascular trauma was penetrating in 18 patients and blunt in 19 patients. Upper extremities were most frequently injured (39.4%). The treatment methods were primary repair in 21 patients, exploratory laparotomies in 7, radiological interventions in 3, resections and graft interpositions of the pseudoaneurysm in 3, observations in 3 and a bypass graft in 1. Four out of the 37 patients died, and three of these who died had injuried abdominal vessels. Twenty-five of the patients recovered completely, four expired, seven had neuropathy in the course of treatement, one had his limb amputated, and one experienced wound necrosis. Conclusion: Peripheral vessel injuries are commonly accompanied by nerve, muscle, or tendon injuries. Patients without associated fractures or compartment syndrome had good prognosis. Although the time intervals from hospital arrival to definite treatment were the shortest among patients with blunt abdominal vascular injuries, three expired. Therefore, we offer a 'ritical pathway'to improve the outcomes of patients with blunt abdominal vascular injury.

Inhibitory effects of Electroacupuncture & Acupuncture at Hu-gye(SI03), Wijung(BL40),Hu-gye(SI03)ㆍWijung(BL40) on Neuropathic Pain in Rats (위중(委中), 후계(後谿), 위중배후계(委中配後谿) 전침(電鍼) 및 침자(鍼刺)가 백서(白鼠)의 신경병리성(神經病理性) 동통(疼痛) 억제(抑制)에 미치는 영향(影響))

  • Oh, Chang-log;Na, Chang-su;Lyu, Chung-yeol;Cho, Myung-rae
    • Journal of Acupuncture Research
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    • v.22 no.1
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    • pp.77-90
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    • 2005
  • Objective : Neuropathic pain sometimes arises from a partial peripheral nerve injury. This kind of pain is usually accompanied by spontaneous burning pain, allodynia and hyperalgesia. It has been well known that acupuncture is effective to the pain control from ancient time in Asia. However, it is not clear whether Electroacupuncture(EA) & Acupuncture(AC) can control neuropathic pain effectively. The aim of this study is to examine if Electroacupuncture&Acupuncture at Hu-gye(SI03), Wijung(BL4O), Hu-gye(SI03) Wijung(BL40) may be effective to the neuropathic pain (mechanical allodynia cold allodynia) in a rat model of neuropathic pain. Methods : A rat model of neuropathic pain was made by injurying tibial nerve and sural nerve while common peroneal nerve was maintained. After the neuropathic surgery, we examined if the rats exhibited the behavioral signs allodynia. The allodynia was assessed by stimulating the medial malleolus with von frey filament and acetone. Three weeks after the neuropathic surgery, electroacupuncture &, acupuncture stimulation was delivered to Hu-gye(SI03), Wijung(BL40), Hu-gye(SI03) Wijung(BL40) one time a day for one week. After that we examined the withdrawal response of neuropathic rats' legs by von frey filament and acetone stimulation, c-fos and AchE(Acetylcholine esterase) in the periaqe- ductal gray(PAG) of neuropathic rats' brain. Results : 1. Electroacupuncture&Acupuncture at Hu-gye(SI03), Wijung(BL40), Hu-gye(SI03) Wijung(BL4O) significantly decreased the withdrawal response of mechanically allodynia in EA-BL40+SI03 group and AC-SI03 group as compared with control group on 6th day. 2. Electroacupuncture &Acupuncture at Hu-gye(SI03), Wijung(BL40), Hu-gye (SI03) Wijung (BL40) significantly decreased the withdrawal response of chemical allodynia(cold allodynia) in EA-SI03 group, EA-BL40+SI03 group and AC-SI03 group as compared with control group on 6th day. 3. Electroacupuncture & Acupuncture at Hu-gye ( SI03), Wijung (BL40), Hu-gye (SI03) Wijung(BL40) significantly decreased the expression of c-fos in the periaqe- ductal gray(PAC) of neuropathic rats' brain in EA-BL40+SI03 group and AC-SI03 group as compared with control group. 4. Electroacupuncture&Acupuncture at Hu-gye(SI03), Wijung(BL40), Hu-gye (SI03) Wijung(BL40) significantly decreased the expression of AchE in the periaqe- ductal gray(PAG) of neuropathic rats' brain in EA-BL40+SI03 group and AC-SI03 group as compared with control group. Conclusions : Based on the above results it is assumed that Electroacupuncture at Hu-gye(SI03) Wijung(BL40) and Acupuncture at Hu-gye(SI03) can help the treatment of neuropathic pain.

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The Role of Axillary Artery Cannulation in Surgery for Type A Acute Aortic Dissection (급성 상행대동맥 박리증 수술에서 액와동맥 삽관술의 역할)

  • 유지훈;박계현;박표원;이영탁;김관민;성기익;양희철
    • Journal of Chest Surgery
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    • v.36 no.5
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    • pp.343-347
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    • 2003
  • Background: The femoral artery is the most common site of canuulation for cardiopulmonary bypass in surgery for type A aortic dissection. Recently, many surgeons prefer the axillary artery to the femoral artery as the arterial cannulation site for several benefits. We evaluated the safety and usefulness of axillary artery cannulation in surgery for acute type A aortic dissection. Material and Method: Between Oct. 1995 and Sep. 2001, 71 patients underwent operations for acute type A aortic dissection. The arterial cannula was inserted into the axillary artery in 31 patients (AXILLARY group, mean age=56), and into the femoral artery in 40 patients (FEMORAL group, mean age=57). We retrospectively compared the incidence of mortality, morbidities, and hospital course. Result: The mean duration of cardiopulmonary bypass and circulatory arrest were significantly shorier in the AXILLARY group (207 min and 39min, respectively) than in the FEMORAL group (263min and 49 min, respectively; P<0.05). Postoperative hospital stay was significantly shorter in the AXILLARY group than in the FEMORAL group (mean 15 days vs. 35 days, p<0.05). Although there was no difference in the incidence of new-onset permanent neurological dysfunction (3.2%, in the AXILLARY group, 2.5% in the FEMORAL group), the incidence of transient neurological dysfunction was significantly lower in the AXILLARY group (12.9% vs. 25%, p<0.05). In the FEMORAL group, two patients needed urgent conversion to cannulation site due to arch vessel malperfusion. In the AXILLARY group, there was only one patient who had a complication related to the cannulation, i.e., median nerve injury. Conclusion: Axillary artery cannulation was safe and helpful in decreasing the cerebral ischemic time and incidence of transient neuroligcal dysfunction in surgery for acute type A aortic dissection, It enabled us to approach the patients with aortic arch pathology more aggressively.