Spreading depolarization suppression from inter-astrocytic gap junction blockade assessed with multimodal imaging and a novel wavefront detection scheme.

Spreading depolarizations (SDs) are an enigmatic and ubiquitous co-morbidity of neural dysfunction. SDs are propagating waves of local field depolarization and increased extracellular potassium. They increase the metabolic demand on brain tissue, resulting in changes in tissue blood flow, and are associated with adverse neurological consequences including stroke, epilepsy, neurotrauma, and migraine.

Effects of In Vivo Intracellular ATP Modulation on Neocortical Extracellular Potassium Concentration.

Neuronal and glial activity are dependent on the efflux of potassium ions into the extracellular space. Efflux of K is partly energy-dependent as the activity of pumps and channels which are involved in K transportation is ATP-dependent. In this study, we investigated the effect of decreased intracellular ATP concentration ([ATP]i) on the extracellular potassium ion concentration ([K]o).

In Vivo Neocortical [K]o Modulation by Targeted Stimulation of Astrocytes.

A normally functioning nervous system requires normal extracellular potassium ion concentration ([K]o). Throughout the nervous system, several processes, including those of an astrocytic nature, are involved in [K]o regulation. In this study we investigated the effect of astrocytic photostimulation on [K]o.

Neocortical in vivo focal and spreading potassium responses and the influence of astrocytic gap junctional coupling.

Raised extracellular potassium ion (K) concentration is associated with several disorders including migraine, stroke, neurotrauma and epilepsy. K spatial buffering is a well-known mechanism for extracellular K regulation/distribution. Astrocytic gap junction-mediated buffering is a controversial candidate for K spatial buffering.

Deep brain stimulation restores the glutamatergic and GABAergic synaptic transmission and plasticity to normal levels in kindled rats.

Background: The precise effect of low frequency stimulation (LFS) as a newly postulated, anticonvulsant therapeutic approach on seizure-induced changes in synaptic transmission has not been completely determined.

Hypothesis: In this study, the LFS effect on impaired, synaptic plasticity in kindled rats was investigated.

Methods: Hippocampal kindled rats received LFS (4 trials consisting of one train of 200 monophasic square waves, 0.

Hungry Neurons: Metabolic Insights on Seizure Dynamics.

Epilepsy afflicts up to 1.6% of the population and the mechanisms underlying the appearance of seizures are still not understood. In past years, many efforts have been spent trying to understand the mechanisms underlying the excessive and synchronous firing of neurons.