Dataset Information

Pacemaker GABA synaptic activity may contribute to network synchronization in pediatric cortical dysplasia.

ABSTRACT: Spontaneous pacemaker ?-aminobutyric acid (GABA) receptor-mediated synaptic activity (PGA) occurs in a subset of tissue samples from pediatric epilepsy surgery patients. In the present study, based on single-cell electrophysiological recordings from 120 cases, we describe the etiologies, cell types, and primary electrophysiological features of PGA. Cells displaying PGA occurred more frequently in the areas of greatest anatomical abnormality in cases of focal cortical dysplasia (CD), often associated with hemimegalencephaly (HME), and only rarely in non-CD etiologies. PGA was characterized by rhythmic synaptic events (5-10Hz) and was observed in normal-like, dysmorphic cytomegalic, and immature pyramidal neurons. PGA was action potential-dependent, mediated by GABAA receptors, and unaffected by antagonism of glutamate receptors. We propose that PGA is a unique electrophysiological characteristic associated with CD and HME. It could represent an abnormal signal that may contribute to epileptogenesis in malformed postnatal cortex by facilitating pyramidal neuron synchrony.

SUBMITTER: Cepeda C

PROVIDER: S-EPMC3877734 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Pacemaker GABA synaptic activity may contribute to network synchronization in pediatric cortical dysplasia.

Cepeda Carlos C Chen Jane Y JY Wu Joyce Y JY Fisher Robin S RS Vinters Harry V HV Mathern Gary W GW Levine Michael S MS

Neurobiology of disease 20131010

Spontaneous pacemaker γ-aminobutyric acid (GABA) receptor-mediated synaptic activity (PGA) occurs in a subset of tissue samples from pediatric epilepsy surgery patients. In the present study, based on single-cell electrophysiological recordings from 120 cases, we describe the etiologies, cell types, and primary electrophysiological features of PGA. Cells displaying PGA occurred more frequently in the areas of greatest anatomical abnormality in cases of focal cortical dysplasia (CD), often associ ...[more]

PMID: 24121115

Similar Datasets

Project description:BackgroundThe cerebral cortex is permanently active during both awake and sleep states. This ongoing cortical activity has an impact on synaptic transmission and short-term plasticity. An activity pattern generated by the cortical network is a slow rhythmic activity that alternates up (active) and down (silent) states, a pattern occurring during slow wave sleep, anesthesia and even in vitro. Here we have studied 1) how network activity affects short term synaptic plasticity and, 2) how synaptic transmission varies in up versus down states.Methodology/principal findingsIntracellular recordings obtained from cortex in vitro and in vivo were used to record synaptic potentials, while presynaptic activation was achieved either with electrical or natural stimulation. Repetitive activation of layer 4 to layer 2/3 synaptic connections from ferret visual cortex slices displayed synaptic augmentation that was larger and longer lasting in active than in silent slices. Paired-pulse facilitation was also significantly larger in an active network and it persisted for longer intervals (up to 200 ms) than in silent slices. Intracortical synaptic potentials occurring during up states in vitro increased their amplitude while paired-pulse facilitation disappeared. Both intracortical and thalamocortical synaptic potentials were also significantly larger in up than in down states in the cat visual cortex in vivo. These enhanced synaptic potentials did not further facilitate when pairs of stimuli were given, thus paired-pulse facilitation during up states in vivo was virtually absent. Visually induced synaptic responses displayed larger amplitudes when occurring during up versus down states. This was further tested in rat barrel cortex, where a sensory activated synaptic potential was also larger in up states.Conclusions/significanceThese results imply that synaptic transmission in an active cortical network is more secure and efficient due to larger amplitude of synaptic potentials and lesser short term plasticity.

Dataset Information

Pacemaker GABA synaptic activity may contribute to network synchronization in pediatric cortical dysplasia.

Publications

Pacemaker GABA synaptic activity may contribute to network synchronization in pediatric cortical dysplasia.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets