title: Developmental Decrease of Neuronal Chloride Concentration Is Independent of Trauma in Thalamocortical Brain Slices.
abstract: The intraneuronal chloride concentration ([Cl-]i) is paramount for determining the polarity of signaling at GABAA synapses in the central nervous system. Sectioning hippocampal brain slices increases [Cl-]i in the superficial layers. It is not known whether cutting trauma also increases [Cl-]i in the neocortex and thalamus, and whether the effects of trauma change during development. We used Cl- imaging to study the [Cl-]i vs. the distance from the cut surface in acute thalamocortical slices from mice at developmental ages ranging from post-natal day 5 (P5) to P20. We demonstrate: 1) [Cl-]i is higher in the most superficial areas in both neocortical and thalamic brain slices at all ages tested and, 2) there is a developmental decrease in [Cl-]i that is independent of acute trauma caused by brain slicing. We conclude that [Cl-]i has a developmental progression during P5-20 in both the neocortex and thalamus. However, in both brain regions and during development the neurons closest to the slicing trauma have an elevated [Cl-]i.
authors.affiliation: Department of Neurology, Division of Child Neurology, Massachusetts General Hospital, Boston, Massachusetts, United States of America.|Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Joseph
authors.initials: J
authors.lastname: Glykys
authors.affiliation: Department of Neurology, Division of Child Neurology, Massachusetts General Hospital, Boston, Massachusetts, United States of America.|Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Staley
mesh_terms: D000818:Animals; D000070642:Brain Injuries, Traumatic / Q000378:metabolism* / Q000473:pathology; D002712:Chlorides / Q000378:metabolism*; D004195:Disease Models, Animal; D018450:Disease Progression; D051379:Mice; D019579:Neocortex / Q000378:metabolism / Q000473:pathology; D009474:Neurons / Q000378:metabolism*; D013788:Thalamus / Q000378:metabolism*
chemical_list: D002712:Chlorides