====== Astrocyte ======
{{ ::astrocyte.jpg|}}

[[Astrocyte]]s contribute to the [[development]] and [[regulation]] of the higher-level [[brain function]]s, the critical targets of [[evolution]].

[[Astrocyte]]s are a type of [[glial cell]] in the [[central nervous system]] (CNS), and they play a crucial role in supporting the function and health of [[neuron]]s.

Astrocytes (Astro from Greek astron = star and cyte from Greek "kyttaron" = cell), also known collectively as [[astroglia]], are characteristic star-shaped glial cells in the brain and spinal cord. They are the most abundant cells of the human brain. 
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Diffuse [[glioma]] is a term used to encompass a variety of poorly marginated infiltrating [[central nervous system tumor]], which histologically appear similar to [[Glial cell]]s, specifically [[astrocyte]]s and [[oligodendrocyte]]s. These range in biological behavior from very indolent to extremely aggressive and this is reflected in grading that ranges from grade 1 to grade 4.
====Functions====
They perform a wide array of functions, yet the nature of their cellular heterogeneity and how it oversees these diverse roles remains shrouded in mystery.

Functions include biochemical support of endothelial cells that form the blood–brain barrier, provision of nutrients to the nervous tissue, maintenance of extracellular ion balance, and a role in the repair and scarring process of the brain and spinal cord following traumatic injuries.

Research since the mid-1990s has shown that astrocytes propagate intercellular Ca2+ waves over long distances in response to stimulation, and, similar to neurons, release transmitters (called gliotransmitters) in a Ca2+-dependent manner. Data suggest that astrocytes also signal to neurons through Ca2+-dependent release of glutamate.

Such discoveries have made astrocytes an important area of research within the field of neuroscience.

[[Kynurenic acid]] (KYNA) is the end stage metabolite of tryptophan produced mainly by [[astrocyte]]s in the central nervous system (CNS). 


Findings indicate a critical contribution of [[astrocyte]]s, star-shaped glial cells in the brain, to neuronal and network excitability and [[seizure]] activity.  Furthermore, many important cellular and molecular changes occur in astrocytes in epileptic tissue in both humans and animal models of [[epilepsy]]. 

===== Types =====

[[Astrocyte Types]].



==== Perivascular astrocyte endfeet ====
[[Perivascular astrocyte endfeet]].

==== Primate astrocyte ====
[[Primate astrocyte]]

====Books====
__Astrocytes and Epilepsy__
By Jacqueline A. Hubbard, Devin K. Binder

The goal of Astrocytes and Epilepsy is to comprehensively review exciting findings linking changes in astrocytes to functional changes responsible for epilepsy for the first time in book format.  These insights into astrocyte contribution to [[seizure]] susceptibility indicate that astrocytes may represent an important new therapeutic target in the control of epilepsy.

Astrocytes and Epilepsy includes background explanatory text on astrocyte morphology and physiology, epilepsy models and syndromes, and evidence from both human tissue studies and animal models linking functional changes in astrocytes to epilepsy.  Beautifully labelled diagrams are presented and relevant figures from the literature are reproduced to elucidate key findings and concepts in this rapidly emerging field.  Astrocytes and Epilepsy is written for neuroscientists, epilepsy researchers, astrocyte investigators as well as neurologists and other specialists caring for patients with epilepsy.

Presents the first comprehensive book to synthesize historical and recent research on astrocytes and epilepsy into one coherent volume.
    
Provides a great resource on the field of astrocyte biology and astrocyte-neuron interactions.
    
Details potential therapeutic targets, including chapters on gap junctions, water and [[potassium channel]]s, [[glutamate]] and adenosine metabolism, and inflammation.

===== Astrocyte Biomarkers in Alzheimer's Disease =====
[[Astrocyte Biomarkers in Alzheimer's Disease]]