Figure 4.

IL3-Tg exhibit a loss of MN and axonal degeneration in the spinal cord. (A–D) ChAT immunoreactivity (ChAT antibody, 1:100) of coronal sections from a 10-month-old control (A and C) or transgenic lumbar spinal cord (B and D). C and D are higher magnifications (×20) of selected areas in A and B (×10), respectively. In addition to their shrunken size, there is a reduced number of ChAT-positive MN in IL3-Tg (B and D) compared with controls (A and C). (E–K) NF₂₀₀ immunoreactivity (NF₂₀₀ antibody 1:200) of coronal sections from an 11-month-old control (E and G) or transgenic (F and H–K) lumbar spinal cord. G and H are higher magnification views (×20) of E and F (×10), respectively. I–K are ×40 magnifications of various sections of the same transgenic animal. Note the axonal neuronal degeneration in transgenic (H) compared with controls (G), as monitored by the dramatic loss of NF₂₀₀ staining. The arrows in H–K show the accumulation of neurofilaments in the neuronal cell body and proximal axons of some MN in IL3-Tg. Similar accumulations were also observed at earlier stages of the disease (i.e., presenting a milder paralysis of limbs).