Effect of PEA on DRG biomolecular and morphological changes induced by granuloma. The effect of granulomatous inflammation on the biomolecular and morphological changes in the DRGs was associated with increased expression of TNF-α (A), NGF (B) and COX-2 (C). The levels of all proteins studied were significantly reduced by PEA treatment as revealed by Western blot analysis (A, B and C upper panels). Our results show that TNF-α and NGF were expressed by neurons as revealed by double labeling with TRPV1 receptor expressed in the DRG (A and B bottom panel) while COX-2 was highly expressed by satellite glial cells identified by glutamine synthetase staining (C bottom panel). Results are expressed as mean ± SEM of 3 experiments. ***p < 0.001 vs saline; °°°p < 0.001 vs λ-carrageenin alone.