title: Hippocampal GABA transporter distribution in patients with temporal lobe epilepsy and hippocampal sclerosis.
abstract: OBJECTIVE
  To determine hippocampal expression of neuronal GABA-transporter (GAT-1) and glial GABA-transporter (GAT-3) in patients with temporal lobe epilepsy (TLE) and hippocampal sclerosis (HS).
  
  
  METHODS
  Hippocampal sections were immunohistochemically stained for GABA-transporter 1 and GABA-transporter-3, followed by quantification of the immunoreactivity in the hilus by optical density measurements. GABA-transporter 3 positive hilar cells were counted and GABA-transporter protein expression in sections that included all hippocampal subfields was quantified by Western blot.
  
  
  RESULTS
  The hilar GABA-transporter 1 expression of patients with severe hippocampal sclerosis was about 7% lower compared to that in the mild hippocampal sclerosis/control group (p<0.001). The hilar GABA-transporter 3 expression was about 5% lower in the severe hippocampal sclerosis group than in the mild hippocampal sclerosis/control group (non-significant). Also, severe hippocampal sclerosis samples contained 34% less (non-significant) GABA-transporter 3 positive cells compared to that of controls. Protein expression as assessed by Western blot showed that GABA-transporter 1 was equally expressed in mild and severe hippocampal sclerosis samples, whereas GABA-transporter 3 was reduced by about 62% in severe hippocampal sclerosis samples (p<0.0001).
  
  
  CONCLUSIONS
  These data confirm that GABA-transporter expression is spatially and isoform-specific reduced and GABA-transporter 3 positive cell numbers are unchanged in hippocampal sclerosis. Implications for the use of GABAergic antiepileptic therapies in hippocampal sclerosis vs non-hippocampal sclerosis patients remain to be studied.
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, The Netherlands. Electronic address: o.schijns@mumc.nl.
authors.forename: Olaf
authors.initials: O
authors.lastname: Schijns
authors.affiliation: Departments of School of Mental Health and Neuroscience, Maastricht University Medical Center, The Netherlands.
authors.forename: Ümit
authors.initials: Ü
authors.lastname: Karaca
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, The Netherlands; Departments of School of Mental Health and Neuroscience, Maastricht University Medical Center, The Netherlands.
authors.forename: Pablo
authors.initials: P
authors.lastname: Andrade
authors.affiliation: Departments of School of Mental Health and Neuroscience, Maastricht University Medical Center, The Netherlands.
authors.forename: Laurence
authors.initials: L
authors.lastname: de Nijs
authors.affiliation: Departments of Pathology, Maastricht University Medical Center, The Netherlands.
authors.forename: Benno
authors.initials: B
authors.lastname: Küsters
authors.affiliation: Departments of Clinical Epidemiology and Medical Technology Assessment, Maastricht University Medical Center, The Netherlands.
authors.forename: Andrea
authors.initials: A
authors.lastname: Peeters
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, The Netherlands.
authors.forename: Jim
authors.initials: J
authors.lastname: Dings
authors.affiliation: Departments of Neurosurgery, Epilepsy Center, Bielefeld, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Pannek
authors.affiliation: Departments of Epileptology, Epilepsy Center, Bielefeld, Germany.
authors.forename: Alois
authors.initials: A
authors.lastname: Ebner
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, The Netherlands.
authors.forename: Kim
authors.initials: K
authors.lastname: Rijkers
authors.affiliation: Departments of Neurosurgery, Maastricht University Medical Center, The Netherlands; Departments of School of Mental Health and Neuroscience, Maastricht University Medical Center, The Netherlands.
authors.forename: Govert
authors.initials: G
authors.lastname: Hoogland
mesh_terms: D000293:Adolescent; D000328:Adult; D001344:Autopsy; D002648:Child; D002675:Child, Preschool; D004833:Epilepsy, Temporal Lobe / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D005260:Female; D050485:GABA Plasma Membrane Transport Proteins / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D012598:Sclerosis; D009435:Synaptic Transmission; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D050485:GABA Plasma Membrane Transport Proteins; C493413:SLC6A1 protein, human; C493416:SLC6A11 protein, human
keywords: GABA-transporter; Hilus; Hippocampal sclerosis; Temporal lobe epilepsy