Hippocampal sclerosis in feline epilepsy.
Hippocampal sclerosis (HS) refers to loss of hippocampal neurons and astrogliosis. In temporal lobe epilepsy (TLE), HS is a key factor for pharmacoresistance, even though the mechanisms are not quite understood. While experimental TLE models are available, there is lack of models reflecting the natural HS development. Among domestic animals, cats may present with TLE-like seizures in natural and experimental settings. With this study on the prevalence, segmental pattern and clinicopathological correlates of feline HS, we evaluated the translational value for human research. Evaluation schemes for human brains were applied to epileptic cats. The loss of neurons was morphometrically assessed and the degree of gliosis was recorded. Hippocampal changes resembling human HS were seen in about one third of epileptic cats. Most of these were associated with infiltrative diseases such as limbic encephalitis. Irrespective of the etiology and semiology of seizures, total hippocampal sclerosis was the most prevalent form seen in epileptic animals. Other HS types also occur at varying frequencies. Segmental differences to human HS can be explained by species-specific synaptic connectivities and a different spectrum of etiologies. All these variables require consideration when translating results from feline studies regarding seizure-associated changes of the temporal lobe and especially HS.
Section of Clinical & Comparative Neuropathology, Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig Maximilians University of Munich, Munich, Germany.
Eva
E
Wagner
Marco
M
Rosati
Jessica
J
Molin
Ulrike
U
Foitzik
Andrea M
AM
Wahle
Andrea
A
Fischer
Lara A
LA
Matiasek
Sven
S
Reese
Thomas
T
Flegel
Kaspar
K
Matiasek
D000818:Animals; D000927:Anticonvulsants / Q000627:therapeutic use; D002371:Cat Diseases / Q000188:drug therapy / Q000473:pathology*; D002415:Cats; D002452:Cell Count; D004827:Epilepsy / Q000150:complications / Q000188:drug therapy / Q000473:pathology / Q000662:veterinary*; D005260:Female; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology*; D008297:Male; D017966:Pyramidal Cells / Q000187:drug effects / Q000473:pathology; D012598:Sclerosis; D013702:Temporal Lobe / Q000187:drug effects / Q000473:pathology
D000927:Anticonvulsants
MTLS; TLE; feline; hippocampus temporal lobe epilepsy; mesial temporal lobe sclerosis; seizure