Neuroglia, or glial cells, are non-neuronal cells in the nervous system that support, protect, and maintain the proper functioning of neurons.
They play vital roles in providing structural support, modulating synaptic transmission, and maintaining the extracellular environment.
There are several types of glial cells, each with specific functions
The classification of neuroglia cells can be divided into two main categories based on their location within the central nervous system (CNS) and peripheral nervous system (PNS)
Central Nervous System (CNS) Glial Cells:
1. Astrocytes:
Provide structural support, regulate extracellular environment, modulate synaptic transmission, and contribute to the blood-brain barrier.
2. Oligodendrocytes:
Produce the myelin sheath that insulates axons, promoting faster signal transmission in the CNS.
3. Microglia:
Act as the primary immune defence, surveilling for damage or pathogens, and removing debris through phagocytosis.
4. Ependymal cells:
Line the ventricles of the brain and the central canal of the spinal cord, playing a role in the production, circulation, and absorption of cerebrospinal fluid.
Peripheral Nervous System (PNS) Glial Cells:
1. Schwann cells:
Produce the myelin sheath that insulates axons in the PNS and support axonal regeneration.
2. Satellite cells:
Surround neuronal cell bodies in sensory, sympathetic, and parasympathetic ganglia, providing structural support and regulating the extracellular environment.