The effect of peripheral axon crush on the axonal transport of the neurotrophin receptors, p75(NTR) and trkA, was studied in dorsal roots of adult rats. Lumbar dorsal roots were crushed for 3-6 h to cause accumulation of p75(NTR) and trkA. Immunohistochemistry showed the presence of the NGF receptors in axons, indicating retrograde and anterograde axonal transport in the dorsal root. Western blots confirmed that the time course of accumulation of p75(NTR) was consistent with fast axonal transport. However, trkA accumulation was too low to indicate significant levels of axonal transport. Sciatic nerve crush induced a 2-fold increase (P<0.05) in the bidirectional axonal transport of p75(NTR) in the dorsal root while trkA transport remained below detectable levels.