Intrathecal Resiniferatoxin Modulates TRPV1 in DRG Neurons and Reduces TNF-Induced Pain-Related Behavior

Figure 1

Influence of intrathecal administration of TNF and TNF + RTX on mechanical allodynia. (a) Administration of NaCl or RTX did not affect paw withdrawal thresholds, compared to control conditions (). (b) While 2 ng TNF does not influence paw withdrawal threshold 1, 3, or 6 h after administration, withdrawal threshold was reduced after 24 h (). Additional administration of RTX (1.9 mg/kg) did not abolish the TNF-induced reduction of withdrawal threshold 1 h, 3 h, 6 h, or 24 h after injection (). (c) Administration of TNF (20 ng) or the combination of TNF + RTX did not change paw withdrawal threshold (). (d) In contrast, administration of 200 ng TNF led to a reduction of paw withdrawal threshold after 24 h (). Additional administration of RTX abolished the effect of TNF after 24 h ().

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