Which glial cell helps regulate the chemical environment of the synaptic gap and provides structural support for neurons?

Which glial cell helps regulate the chemical environment of the synaptic gap and provides structural support for neurons?

• A. Schwann cells
• B. Oligodendrocytes
• C. Astrocytes
• D. Microglia

Answer: (C)

Astrocytes are star-shaped glial cells in the central nervous system that provide structural support for neurons and actively regulate the chemical environment around synapses. They help maintain ionic balance by buffering extracellular potassium that accumulates during neuronal firing, and they clear neurotransmitters such as glutamate and GABA from the synaptic cleft, which keeps synaptic signaling precise and prevents excessive excitation. They also interact with blood vessels to support the blood–brain barrier and metabolically nourish neurons, contributing to overall synaptic health. This combination of maintaining the chemical milieu of the synapse and offering physical scaffolding makes them the best fit for the described roles. By contrast, Schwann cells myelinate peripheral nerves, oligodendrocytes myelinate CNS axons, and microglia function mainly in immune defense and debris cleanup.

Astrocytes are star-shaped glial cells in the central nervous system that provide structural support for neurons and actively regulate the chemical environment around synapses. They help maintain ionic balance by buffering extracellular potassium that accumulates during neuronal firing, and they clear neurotransmitters such as glutamate and GABA from the synaptic cleft, which keeps synaptic signaling precise and prevents excessive excitation. They also interact with blood vessels to support the blood–brain barrier and metabolically nourish neurons, contributing to overall synaptic health. This combination of maintaining the chemical milieu of the synapse and offering physical scaffolding makes them the best fit for the described roles. By contrast, Schwann cells myelinate peripheral nerves, oligodendrocytes myelinate CNS axons, and microglia function mainly in immune defense and debris cleanup.