Retrograde labelling of DRG after sciatic nerve injury. Anatomical analyses of regeneration of sensory axons after sciatic nerve injuries in wild-type versus knockout mice. Figs. 7a-c show composite images made up by merging the entire z-series of optical sections through L5 DRG in wild-type (Fig. 7a) and knockout mice (Fig. 7b) 13 days after sciatic nerve crush and 2 days after injection of DiAsp into the skin of the hindpaw. Fig. 7c shows the control DRG (no sciatic nerve injury) from the same animal as Fig. 7b. Figs. 7d and e show a similar comparison of labelling in wild-type and knockout mice 90 days after sciatic nerve crush. Scale bar = 200 μm and applies to Figs. 7a-e. Figs. 7f and g compare the numbers of labelled cells in L5 DRG 13 days (Fig. 7f) and 90 days (Fig. 7g) after sciatic nerve crush in wild-type (N = 8 + 8; black columns) versus knockout mice (N = 8 + 8; grey columns). The quantitative analyses show that there are no statistically significant differences in the numbers of retrogradely labelled DRG cells (and thus in the extent of sensory axon regeneration) between wild-type and knockout mice at either short or long postoperative survival times.