Differences in levels for Plexin A4 and EphA4 antibody staining between spinal levels. A,B, Plexin A4 receptor expression visualized through antibody fluorescence was evident in the peripheral region of cervicothoracic and thoracic DRG explants. C, Receptor expression was observed in the periphery as well as the central region of lumbosacral DRG explants. D, Relative fluorescence units plotted across DRG spinal level demonstrated increase mean values in lumbosacral compared to thoracic or cervicothoracic DRG explants. E–G, EphA4 was faintly visible in the peripheral regions of all three spinal levels. H, Relative fluorescence units were all less than Plexin A4 levels and were not significantly different among spinal levels. One-way ANOVA performed separately followed by the Games-Howell post-hoc analysis (n=6, **p < 0.01).