Astrocytic

Astrocytic is an adjective describing anything related to astrocytes, star-shaped glial cells in the brain and spinal cord. Astrocytes are a major class of glia that support neuronal function, participate in the formation and maintenance of the blood–brain barrier, and help regulate the extracellular environment of neural tissue.

Key astrocytic functions include clearance of neurotransmitters such as glutamate and GABA through specialized transporters, buffering of extracellular potassium after neuronal activity, and metabolic support for neurons via glycolysis and the astrocyte–neuron lactate shuttle. Astrocytic processes extend to synapses and blood vessels, and their endfeet contribute to vascular regulation and barrier integrity. Calcium signaling within astrocytes underlies a form of gliotransmission that can modulate synaptic activity and network dynamics.

In development and anatomy, astrocytes arise from neural progenitor cells and differentiate under signals that shape the mature CNS. Astrocytic markers such as GFAP and S100β are commonly used in research and pathology to identify astrocytic lineage.

Clinical relevance includes reactive astrocytosis (astrogliosis), a response to CNS injury or disease characterized by astrocyte hypertrophy and GFAP upregulation. Astrocytomas are tumors derived from astrocytic lineage, ranging from relatively indolent forms to aggressive glioblastomas. Dysfunction of astrocytic processes has been implicated in various neurological disorders, including epilepsy, neurodegenerative diseases, and cognitive deficits, through impaired neurotransmitter clearance, ion homeostasis, and metabolic support.