Fig. 8.

Nerve cell loss in spinal cords from mice of the human P301S tau line. A, B, Hematoxylin and eosin-stained sections of the ventral gray matter of the spinal cord (level L2–L3) from a 6-month-old control mouse (A) and a transgenic mouse (B) of the same age. Swollen, abnormal material-containing motor neurons are indicated byarrows. Arrowheads point to atrophic motor neurons, with dashed arrows pointing to pyknotic cells that are surrounded by glial cells, suggestive of neuronophagia.C, Graph showing the density of motor neurons (expressed as number of neurons per millimeter square) in the anterior horn of the lumbar spinal cord from 6-month-old control and human P301S tau transgenic mice. Nerve cell numbers were determined in five consecutive sections from each animal, with the density of motor neurons from each section being represented by a circle. The results are expressed as the means ± SEM (n = 3); *p < 0.0001. Scale bar: A, 60 μm (for A, B).