• Title/Summary/Keyword: Pain%3A hyperalgesia

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Dual Effect of Dynorphin A on Single-Unit Spike Potentials in Rat Trigeminal Nucleus

  • Lee, Keun-Mi;Han, Hee-Seok;Jang, Jae-Hee;Ahn, Doug-Kuk;Park, Jae-Sik
    • The Korean Journal of Physiology and Pharmacology
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    • v.5 no.3
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    • pp.213-221
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    • 2001
  • The amygdala is known as a site for inducing analgesia, but its action on the trigeminal nucleus has not been known well. Little information is available on the effect of dynorphin on NMDA receptor-mediated electrophysiological events in the trigeminal nucleus. The purpose of this study was to investigate the changes in the single neuron spikes at the trigeminal nucleus caused by the amygdala and the action of dynorphin on the trigeminal nucleus. In the present study, extracellular single unit recordings were made in the dorsal horn of the medulla (trigeminal nucleus caudalis) and the effects of microiontophoretically applied compounds were examined. When [D-Ala2, N-Me-Phe4, Glys5-ol]enkephalin (DAMGO, 10-25 mM), a ${\mu}-opioid$ receptor agonist, was infused into the amygdala, the number of NMDA-evoked spikes at the trigeminal nucleus decreased. However, the application of naloxone into the trigeminal nucleus while DAMGO being infused into the amygdala increased the number of spikes. Low dose (1 mM) of dynorphin in the trigeminal nucleus produced a significant decrease in NMDA-evoked spikes of the trigeminal nucleus but the NMDA-evoked responses were facilitated by a high dose (5 mM) of dynorphin. After the ${\kappa}$ receptors were blocked with naloxone, dynorphin induced hyperalgesia. After the NMDA receptors were blocked with AP5, dynorphin induced analgesia. In conclusion, dynorphin A exerted dose-dependent dual effects (increased & decreased spike activity) on NMDA-evoked spikes in the trigeminal nucleus. The inhibitory effect of the dynorphin at a low concentration was due to the activation of ${\kappa}$ receptors and the excitatory effect at a high concentration was due to activation of NMDA receptors in the trigeminal neurons.

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Treatment of CRPS Type-I with Fire and Water Acupoints: A Case Report (오수혈의 화(火)혈과 수(水)혈의 운용을 통한 CRPS 제1형 환자 치험 1례)

  • Kim, Jong Han;Yoo, Je Hyuk;Park, Ji Min;Lee, Seung Min;Im, Se Hoon;Lee, Sang Hoon;Lee, Jae Dong;Nam, Dong Woo
    • Journal of Acupuncture Research
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    • v.30 no.3
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    • pp.165-171
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    • 2013
  • Objectives : The purpose of this study is to investigate the effect of acupuncture treatment on a patient suffering from CRPS Type 1. Methods : A 30-year-old female patient suffering from CRPS Type 1 with symptoms of intense burning pain, joint stiffness, restricted mobility, rapid hair and nail growth, allodynia, hyperalgesia and coldness of the right leg was treated with acupuncture on six acupuncture points on the leg from 13 July to 18 July of 2011. Improvement of the patient's symptoms was evaluated by Numerical Rating Scale(NRS), Digital Infrared Thermographic Image(DITI). Results : After 6 days of treatment, NRS score decreased significantly and the DITI results showed moderate improvement in temperature. Conclusions : The results suggest that acupuncture may be an effective in reducing the symptoms of CRPS. Further study is needed to evaluate the significancy of this report.