Figure 6.

GDF15 and HB-EGF receptors are differentially expressed in the spinal cords of presymptomatic mice. (A) Quantitative RT-PCR was performed on total RNA isolated from the spinal cords of 3-month-old wildtype and SOD1^G93A mice. Transcript levels of Egfr, Erbb4, Gfral, Tgfbr1, and Tgfbr2 were expressed relative to polymerase (RNA) II polypeptide J (Polr2J) transcript. The expression levels of each transcript in the spinal cords of SOD1^G93A mice were normalized to those obtained in the spinal cords of wildtype mice (represented by the dashed line). Values are means ± SEM, the number of mice is indicated in brackets. Data were analyzed by Mann–Whitney test. * p < 0.05, ** p < 0.01 vs. wildtype spinal cord. (B) Lumbar spinal cord sections of wildtype and SOD1^G93A mice at 3 months of age were immunostained with antibodies against TGFβ-R1 (in green) and ChAT (in red). Scale bar, 50 µm.