Figure 1

Choline acetyltransferase (ChAT) immunoreactivities in the spinal cord and DRG. (A) ChAT-immunoreactivities in fiber-like structures of lamina I–III regions of the dorsal horn, lamina X and in discrete lamina IX regions of ventral horn. Representative picture of fiber-like structures; discrete lamina IX regions are marked in the figure (A-1). (A-2) Many fiber-like structures (inset in a) were observed, in contrast to the very few ChAT-positive cell bodies (inset in b) observed, in dorsal laminae I–III. Representative picture of the intense ChAT signals found in the motor neurons of the lamina IX region (A-3). (B, C) Double-immunostaining for ChAT (green) and the neuronal marker NeuN (red) in the lamina I–III region (B), and in the lamina IX region (C). Note that ChAT-signals in the lamina I–III region (B) are not observed in neuronal cell bodies labeled by anti-NeuN IgG, while those in the lamina IX region (C) are always labeled by this IgG. (D) Representative picture of ChAT-immunoreactivities in the DRG. ChAT signals were found in most cells across the size spectrum (inset in a). (E) Double-immunostaining for ChAT (red) and the unmyelinated C-fiber marker IB4 (green) in the DRG. (F) Double-immunostaining for ChAT (red) and the myelinated A-fiber marker N52 (green). Scale bar = 20 μm for (B, C), and 50 μm for (A-2a, A-2b, A-3, D, E, F). (G) Western blot analysis using rabbit antiserum showing one 68-kDa immunoreactive band for ChAT. The 55-kDa immunoreactive band for β-tubulin is also indicated at the bottom. DH: spinal dorsal horn and VH: spinal ventral horn.