Neuropeptide Y and galanin are coexpressed in rat large type A sensory neurons after peripheral transection

Neuropeptide Y (NPY)-like immunoreactivity (IR) was observed in 20-30% of ipsilateral dorsal root ganglion (DRG) neurons (L4-5) after unilateral transection of rat sciatic nerve. Most of these neurons contained 200 kDa subunit of neurofilaments and galanin. Immunohistochemical analysis combined with retrograde tracing method demonstrated that NPY-IR was detected in cutaneous and muscular sensory, but not in visceral sensory neurons. These findings suggest that NPY coexists with galanin in injured large type A cells, which may innervate the mechanoreceptors in the skin and muscle, such as corpuscles of Meissner and Pacini, or muscle spindles.