Figure 2

Representative sections of C8 dorsal root ganglion and spinal cord segment. A. A schematic drawing of double retrograde labeling of neurons following end-to-side neurorrhaphy of MCN stump with UN. FE – Fluoro-Emerald, FR – Fluoro-Ruby. B, C. Representative cryostat sections of C8 dorsal root ganglion (B) and C8 spinal cord segment (C) from rat 2 months after ETS neurorrhaphy of the MCN stump transfected with plasmid phVEGF illustrating retrograde labeled primary sensory and motor neurons. Red fluorescence labeled neurons with axons present only in the UN distal to ETS neurorrhaphy. Green fluorescence loaded neurons whose axons were damaged during surgical treatment and regenerated only into the MCN distal stump. Yellow fluorescence of labeled neurons (arrows) resulted from a mixture of red and green fluorescence indicating the neurons, the donor axons of which were present in the UN that had sent out collateral sprouts into the distal stump of the MCN. Scale bars = 100 μm