FIGURE 1.

Biochemical assessment of tau pathology in essential tremor compared to Alzheimer disease and sporadic tauopathies. (A–D) Immunohistochemical studies were performed in parallel samples derived from the fresh frozen temporal cortex tissue block (Brodmann area 37) used for biochemical analysis to assess the presence of tau pathology using antisera recognizing tau phosphorylated at Ser202, Thr205, and Ser208 (p-tau, AT8). This analysis revealed a spectrum from low tau pathology consisting of minimal to scattered thread pathology (A, B), to high levels of tau pathology, consisting of marked neuronal pathology including neurons and dystrophic neurites (C) and/or glial tau pathology (D). Immunoblot using antisera targeting total tau (E–G) or p-tau (H–J) on total protein lysates. ET cases were stratified into high and low p-tau (AT8) groups from biochemical assessments (F, I) and cognitive status (G, J). Measurements were normalized to GAPDH. Two data points of PSP cases in (I) are outside the axis limits (the values are both 0). Scale bar = 100 µm.