Abstract | BACKGROUND: Usually, a barrage of impulses ("injury discharge") is evoked following sensory nerve damage. It has been suggested that injury discharge may produce the hyperexcitatory state in the spinal cord, and this hyperexcitability may cause neurogenic pain. In the present study, the authors examined the role of injury discharge in developing the hyperesthetic state following nerve constriction injury. METHODS: A model of thermal hyperesthesia caused by a constriction injury created by making four loose ligations around the rat sciatic nerve was examined. To block the injury discharge, 0.5% bupivacaine was applied to the sciatic nerve before constriction injury. To block the hyperexcitatory state, (+)- MK-801, an N-methyl-D-aspartate antagonist, was administered intrathecally 15 min before the nerve lesion. RESULTS: CONCLUSION: These results suggest that injury discharge may induce facilitation of spinal dorsal horn neurons, and this spinal facilitation may play an important role in developing thermal hyperesthesia following sciatic nerve constriction injury.
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Authors | T Yamamoto, N Shimoyama, T Mizuguchi |
Journal | Anesthesiology
(Anesthesiology)
Vol. 79
Issue 5
Pg. 993-1002; discussion 28A
(Nov 1993)
ISSN: 0003-3022 [Print] United States |
PMID | 8239018
(Publication Type: Journal Article)
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Chemical References |
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Topics |
- Animals
- Constriction, Pathologic
- Dizocilpine Maleate
(administration & dosage, therapeutic use)
- Hot Temperature
(adverse effects)
- Hyperesthesia
(etiology, prevention & control)
- Injections, Spinal
- Nerve Fibers
(physiology)
- Rats
- Sciatic Nerve
(injuries)
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