Cellular analysis of S100β and fibroblast growth factor-2 in the dorsal root ganglia and sciatic nerve of rodents.: Focus on paracrine actions of activated satellite cells after axotomy

The role of satellite cells, a type of peripheral glia, in the paracrine mechanisms related to neuronal maintenance and plasticity in the dorsal root ganglia (DRG) needs to be further investigated. This study employed immunohistochermstry and image analysis to investigate basic fibroblast growth factor (bFGF, FGF-2) and S100 beta immunoreactivities in the DRG and sciatic nerve of the rat and mouse. Well-characterized antibodies against bovine (residues 1-24) and rat (residues 1-23) FGF-2 were employed. Furthermore, the state of satellite cell reaction and changes in the FGF-2/S100 beta immunoreactivity were analyzed after axotomy of rat sciatic nerve. Scattered neurons and the majority of the satetlite cells of the rat DRG and also Schwann cells of the rat sciatic nerve stained for S100 beta. In the mouse, strong S100 beta was encountered in the majority of sensory neurons and Schwann cells. Moderate FGF-2 (residues 1-24) immunoreactivity was found in scattered small size neurons of the rat DRG. A strong FGF-2 (residues 1-23) immunoreactivity was achieved in the satellite cells of rat DRG. Both FGF-2 antisera showed strong labeling in the mouse DRG sensory neurons. Activated satellite