Fig. 2

Immunohistochemistry and immunofluorescence of the gap junction protein connexin 43 and the satellite cell marker S100 in DRG of normal controls and FA. a-d normal control; e-h FA; a and e positive contrast immunohistochemistry of connexin 43; b and f Alexa 488 immunofluorescence of S100; c and g Cy3 fluorescence of connexin 43; d and h, merged images of b and c, and f and g, respectively. In the normal DRG, connexin 43 shows punctate and coalescing reaction product (a; and inset [arrow]). In FA, a great abundance of connexin 43 reaction product is present in multiple layers around small neurons (e). Hyperplastic satellite cells bridge gaps between neurons. The confocal images of a normal DRG show sparse gap junctions by their punctiform connexin 43 immunofluorescence (c). They are closely related to S100-positive satellite cells (d). In FA, the number of connexin 43-reactive puncta is greatly increased (g and h). Bars: (a) and (e), 20 μm; insets, 10 μm; (b-d) and (f-h), 10 μm. N, neuron