Figure 3. Number of femoral as compared to sciatic motoneurons in the lumbosacral (L2–L4) spinal cord in 4‐month‐old Smn ^+/− transgenic mice and wild type control mice.

Motoneuron counts after backlabelling the femoral or sciatic nerves with either fluorogold or rubyred were completed on consecutive 40 μm thick longitudinal spinal cord sections between T11 and L2; motoneurons in all sections were counted. The data are corrected for thickness of the longitudinal sections. Each bar represents the mean ± SEM of data obtained from 5 (C57BL/6‐wild type) and 6 (C57BL/6‐Smn ^+/− transgenic) mice. Note that the number of motoneurons in the Smn ^+/− transgenic mouse is not different from the wild type control for either femoral (P > 0.91) or sciatic (P > 0.83) nerves at 4 months of age.