Expression of tau immunoreactivity in the spinal motor neurons of Alzheimer's disease.

Tau-related pathology was investigated in the spinal cord of 11 patients with AD. Ten ALS and 10 age-matched neurologically intact patients served as controls. Tau immunoreactivity was detected in neurons of the anterior horn in all AD cases and to a lesser extent in the intermediate zone and in the posterior horn. Tau immunoreactivity was rare in controls. Neurofibrillary tangles were identified in seven AD cases, but none was observed in the controls.