Involvement of peroxisome proliferator-activated receptors on the protective actions of PEA following spinal cord trauma. Following spinal cord compression a significant damage to the spinal cord from wildtype (WT) mice (E) at the perilesional zone was observed by H &E staining when compared with spinal cord tissue collected from the sham group (D). The absence of the peroxisome proliferator-activated receptor (PPAR)-α gene significantly increases the extent and severity of the histological damage (B) when compared with the sham group (A). Treatment with palmitoylethanolamide (PEA, 10 mg/kg) resulted in a significant decrease in the extent and severity of damage (F). The genetic absence of the PPAR-α receptor significantly blocked the effect of the PEA treatment (C). Pretreatment with GW9662 (1 mg/kg (G)) or GSK0660 (1 mg/kg (H)) counteracted the actions of PEA. The histological score (I) was made by an independent observer. These figures are representative of at least three experiments performed on different experimental days. Data are mean ± standard error of the mean of 10 mice for each group. *P <0.05 vs. sham WT; **P <0.01 vs. sham WT; #P <0.05 vs. spinal cord injury (SCI) WT.