Perturbed Chloride Homeostasis and GABAergic Signaling in Human Temporal Lobe Epilepsy

Changes in chloride (Cl-) homeostasis may be involved in the generation of some epileptic activities. In this study, we asked whether Cl- homeostasis, and thus GABAergic signaling, is altered in tissue from patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis. Slices prepared from this human tissue generated a spontaneous interictal-like activity that was initiated in the subiculum. Records from a minority of subicular pyramidal cells revealed depolarizing GABA(A) receptor-mediated postsynaptic events, indicating a perturbed Cl- homeostasis. We assessed possible contributions of changes in expression of the potassium-chloride cotransporter KCC2. Double in situ hybridization showed…

• DC
  Danish Cancer Society Research Center
• IN
  Institut National de la Santé et de la Recherche Médicale
• AO
  Academy of Finland
• CN
  Centre National de la Recherche Scientifique