Cellular pathology of hilar neurons in Ammon's horn sclerosis.

Details

Serval ID
serval:BIB_1C4FC91A7CC7
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Cellular pathology of hilar neurons in Ammon's horn sclerosis.
Journal
Journal of Comparative Neurology
Author(s)
Blümcke I., Zuschratter W., Schewe J.C., Suter B., Lie A.A., Riederer B.M., Meyer B., Schramm J., Elger C.E., Wiestler O.D.
ISSN
0021-9967 (Print)
ISSN-L
0021-9967
Publication state
Published
Issued date
1999
Volume
414
Number
4
Pages
437-453
Language
english
Abstract
In addition to functionally affected neuronal signaling pathways, altered axonal, dendritic, and synaptic morphology may contribute to hippocampal hyperexcitability in chronic mesial temporal lobe epilepsies (MTLE). The sclerotic hippocampus in Ammon's horn sclerosis (AHS)-associated MTLE, which shows segmental neuronal cell loss, axonal reorganization, and astrogliosis, would appear particularly susceptible to such changes. To characterize the cellular hippocampal pathology in MTLE, we have analyzed hilar neurons in surgical hippocampus specimens from patients with MTLE. Anatomically well-preserved hippocampal specimens from patients with AHS (n = 44) and from patients with focal temporal lesions (non-AHS; n = 20) were studied using confocal laser scanning microscopy (CFLSM) and electron microscopy (EM). Hippocampal samples from three tumor patients without chronic epilepsies and autopsy samples were used as controls. Using intracellular Lucifer Yellow injection and CFLSM, spiny pyramidal, multipolar, and mossy cells as well as non-spiny multipolar neurons have been identified as major hilar cell types in controls and lesion-associated MTLE specimens. In contrast, none of the hilar neurons from AHS specimens displayed a morphology reminiscent of mossy cells. In AHS, a major portion of the pyramidal and multipolar neurons showed extensive dendritic ramification and periodic nodular swellings of dendritic shafts. EM analysis confirmed the altered cellular morphology, with an accumulation of cytoskeletal filaments and increased numbers of mitochondria as the most prominent findings. To characterize cytoskeletal alterations in hilar neurons further, immunohistochemical reactions for neurofilament proteins (NFP), microtubule-associated proteins, and tau were performed. This analysis specifically identified large and atypical hilar neurons with an accumulation of low weight NFP. Our data demonstrate striking structural alterations in hilar neurons of patients with AHS compared with controls and non-sclerotic MTLE specimens. Such changes may develop during cellular reorganization in the epileptogenic hippocampus and are likely to contribute to the pathogenesis or maintenance of temporal lobe epilepsy.
Keywords
Aged, Biopsy, Cell Size, Dendrites/pathology, Dendrites/ultrastructure, Epilepsy, Temporal Lobe/pathology, Hippocampus/pathology, Humans, Immunohistochemistry, Microscopy, Electron, Mossy Fibers, Hippocampal/pathology, Mossy Fibers, Hippocampal/ultrastructure, Pyramidal Cells/pathology, Pyramidal Cells/ultrastructure, Sclerosis/pathology
Pubmed
Web of science
Create date
24/01/2008 14:35
Last modification date
20/08/2019 12:52
Usage data