In:
Pain Research and Management, Hindawi Limited, Vol. 20, No. 6 ( 2015), p. 309-315
Kurzfassung:
BACKGROUND: Despite numerous pharmacological approaches, there are no common analgesic drugs that produce meaningful relief for the majority of patients with neuropathic pain. Although nitrous oxide (N 2 O) is a weak analgesic that acts via opioid-dependent mechanisms, it is also an antagonist of the N -methyl-D-aspartate receptor (NMDAR). The NMDAR plays a critical role in the development of pain sensitization induced by nerve injury. OBJECTIVE: Using the chronic constriction injury of the sciatic nerve in male rats as a preclinical model of neuropathic pain, the first aim of the present study was to evaluate the lowest N 2 O concentration and the shortest time of N 2 O postinjury exposure that would produce persistent relief of neuropathic pain. The second aim was to compare the effects of N 2 O with gabapentin, a reference drug used in human neuropathic pain relief. METHODS: Changes in the nociceptive threshold were evaluated using the paw pressure vocalization test in rats. RESULTS: Among the various N 2 O concentrations tested, which ranged from 25% to 50%, only 50% N 2 O single exposure for 1 h 15 min induced a persistent (minimum of three weeks) and significant (60%) reduction in pain hypersensitivity. A single gabapentin dose (75 mg/kg to 300 mg/kg, intraperitoneally) induced an acute (1 h to 1 h 30 min) dose-dependent effect, but not a persistent effect such as that observed with N 2 O. CONCLUSIONS: These preclinical results suggest that N 2 O is advantageous for long-lasting neuropathic pain relief after sciatic nerve injury compared with other drugs used in humans such as gabapentinoids or NMDAR antagonists. The present preclinical study provides a rationale for developing comparative clinical studies.
Materialart:
Online-Ressource
ISSN:
1203-6765
Sprache:
Englisch
Verlag:
Hindawi Limited
Publikationsdatum:
2015
ZDB Id:
2048409-4
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