Fig. 9. Gfap upregulation in grey matter astrocytes in Fgfr3-null mice. Transverse sections through the cervical spinal cords of 2-month-old wild-type (A) and Fgfr3-null mice (B) were immunolabeled with anti-Gfap. In the wild-type cord, white matter (fibrous) astrocytes express Gfap but there is little or no Gfap immunoreactivity in the grey matter. By contrast, the Fgfr3-null mouse (B) shows extensive Gfap labelling of grey matter (protoplasmic) astrocytes. Scale bar: 100 µm.