glial cell
Meaning of glial cell: A glial cell is any of the supporting cells that surround, nourish, and protect neurons without transmitting nerve signals themselves.
Definition of glial cell
A glial cell, also called a cell of the neuroglia, is one of the supporting cells of the nervous system that surrounds and maintains neurons, the nerve cells responsible for transmitting electrical and chemical signals. Glial cells do not transmit signals over distance the way neurons do, but they perform functions essential to how neurons survive and operate.
Recognized types of glial cell include oligodendrocytes and Schwann cells, which form the insulating myelin layer around nerve fibers, astrocytes, which provide structural support and regulate the chemical environment around neurons, microglia, which serve as the nervous system's resident immune cells, and ependymal cells, which line fluid filled spaces within the brain.
Glial cells outnumber neurons in much of the nervous system, and because they support nearly every aspect of neuron health and function, damage affecting glial cells can impair nervous system function even without direct injury to the neurons themselves.
Also known as
Used in a sentence
An increase in glial cells was noted in the area surrounding the damaged nerve tissue.
Good to know
A glial cell supports and maintains neurons rather than transmitting nerve signals itself, a distinction that separates its supportive role from the signaling role that defines a neuron.
Word origin
Where “glial cell” comes from
Formed from Greek glia, meaning glue, describing the supportive role these cells play around neurons.