title: Correlations between granule cell dispersion, mossy fiber sprouting, and hippocampal cell loss in temporal lobe epilepsy.
abstract: OBJECTIVE
  Correlations between granule cell dispersion (GCD), collateral mossy fiber (MF) sprouting, and hippocampal cell loss were studied to assess the relation between GCD and synaptic reorganization in the dentate gyrus of patients with epilepsy.
  
  
  METHODS
  Twenty specimens from patients with medically intractable temporal lobe epilepsy (TLE) were studied along with two control specimens. GCD was considered to be present when the stratum granulosum was wider than 120 microm, the close apposition between the granule cell (GC) soma was lost, and GCs were scattered in the molecular layer (ML). Patterns of MF sprouting were differentiated as wide or narrow according to the area of neo-Timm's staining in the ML. GC loss and volumetric cell-density decreases in the different subfields were assessed.
  
  
  RESULTS
  MF sprouting was observed in 16 (80%) and GCD in nine (45%) cases. A significant correlation was found between MF sprouting and cell loss in all the subfields except the cornu Ammonis field 2 (CA2). A wide band of MF sprouting was associated with severe cell loss. Cases with GCD had a wide band of MF sprouting and also a higher degree of cell loss than cases without GCD.
  
  
  CONCLUSIONS
  GCD is associated with a specific pattern of MF sprouting, but cell loss was found to be a major determinant for MF reorganization.
authors.affiliation: Laboratory of Experimental and Clinical Epileptology, Université Bordeaux, France.
authors.forename: B
authors.initials: B
authors.lastname: El Bahh
authors.forename: V
authors.initials: V
authors.lastname: Lespinet
authors.forename: D
authors.initials: D
authors.lastname: Lurton
authors.forename: M
authors.initials: M
authors.lastname: Coussemacq
authors.forename: G
authors.initials: G
authors.lastname: Le Gal La Salle
authors.forename: A
authors.initials: A
authors.lastname: Rougier
mesh_terms: D000328:Adult; D000368:Aged; D002452:Cell Count; D004396:Coloring Agents; D018891:Dentate Gyrus / Q000166:cytology; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis*; D006624:Hippocampus / Q000166:cytology*; D006801:Humans; D008875:Middle Aged; D019599:Mossy Fibers, Hippocampal / Q000648:ultrastructure*; D009474:Neurons / Q000166:cytology*; D017966:Pyramidal Cells / Q000166:cytology
chemical_list: D004396:Coloring Agents