Pick's disease: cytoskeletal changes in the hypothalamic lateral tuberal nucleus.

Basolateral portions of the human hypothalamus contain an extended nuclear gray, the lateral tuberal nucleus (LTN), which undergoes conspicuous pathological changes in a number of neurodegenerative diseases. The present study points to the severe affliction of this nucleus in Pick's disease (PID). Immunoreactions for abnormally phosphorylated tau-protein permit identification of the permutations. Only a fraction of the abnormal fibrillary material developing in the course of the disease shows a pronounced argyrophilia. Key features are the Pick bodies (PBs) which contain an argyrophilic material. Unusual non-spherical PBs develop in the LTN as flat structures with peripheral indentations. Small teardrop-like Pick neurites (PNs) emerge in varicose widenings of neuronal processes and display a much weaker argyrophilia. The characteristic alterations seen in PID reliably can be differentiated from lesions of the LTN which slowly emerge in the course of Alzheimer's disease (AD).