Fig. 8. Representational sections of skin showing cellular intraplantar nerve growth factor (NGF)–induced infiltration after palmitoylethanolamide (PEA) treatments. A marked cellular infiltration of neutrophils and monocytes (macrophages and mast cells) induced by intraplantar NGF after dimethyl sulfoxide/saline control treatment (a ) is in contrast to a paucity of cellular infiltration associated with 25 mg/kg PEA (b ). Also, fewer cells are evident after coadministration of 1 mg/kg SR141716A (SR1) (c ), but with SR144528 (SR2) the PEA-mediated reduction in cells is reversed (d ). These visual data concur with the results of measurement of absorbance at 620 nm and, hence, myeloperoxidase activity (scale bar: 100 μm).