Abstract | BACKGROUND: OBJECTIVE: METHODS: Thirty male Sprague-Dawley rats were randomly allocated to 5 different groups: (1) sham rats and CPIP rats treated with (2) vehicle; (3) NAC 30 mg/kg; (4) NAC 100 mg/kg; and (5) NAC 300 mg/kg intraperitoneally at 15 minutes before reperfusion. CPIP was generated after a 3-hour ischemia/reperfusion injury on the hind limb using a tight fitting O-ring. Then, mechanical paw-withdrawal thresholds to von Frey stimuli were assessed before ischemia (baseline), at 4 hours; 1, 3, and 5 days; and 1, 2, 3, and 4 weeks after reperfusion. Another set of 5 animal groups in the same categories was used to determine phosphorylated NMDA receptor 1 subunit (pNR1) immunoreactivity in the ipsilateral L4/6 spinal cord at 3 days after reperfusion. RESULTS: The sham group showed no significant difference in pain thresholds over 4 weeks. With NAC treatment, the pain thresholds measured after reperfusion increased significantly, and this increase lasted 4 weeks after reperfusion compared with the vehicle group (P < 0.01 on the ipsilateral side and P < 0.05 on the contralateral side). The relative density of pNR1 at 3 days after reperfusion in NAC-treated rats decreased significantly compared with that of the vehicle group (all, P < 0.001). The NAC dose was significantly correlated not only with paw-withdrawal threshold (ρ = 0.979; P < 0.001) but also with the relative density of pNR1 (ρ = -0.875; P < 0.001). CONCLUSIONS: NAC, administered during the pre-reperfusion period, had a long-term antiallodynic effect through the attenuation of NMDA receptor phosphorylation, leading to central sensitization.
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Authors | Kyung-Hwa Kwak, Dong Gun Lim, Woon Yi Baek |
Journal | Current therapeutic research, clinical and experimental
(Curr Ther Res Clin Exp)
Vol. 72
Issue 5
Pg. 216-27
(Oct 2011)
ISSN: 0011-393X [Print] United States |
PMID | 24653508
(Publication Type: Journal Article)
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