Nonneuronal Cells of the Nervous System

Nonneuronal Cells of the
Nervous System
Melissa Metzler
Glial Cells
 Make
up about 90% of the cells in the
nervous system but only 50% of the
 Cannot generate or transmit nerve signals.
 They are responsible for the physical and
metabolic support of the neurons.
Types of Nonneuronal Cells
 Four
types associated with the central
nervous system.
Astrocytes, oligodendrocytes, microglia, and
ependymal cells
 Two
types associated with the peripheral
nervous system
Satellite cells and Schwann cells.
Star-shaped cell that
provides glucose and
removes ammonia
from the neurons.
 Also regulates
potassium and
around synapses.
Astrocytes Continued…
Form a barrier around the
blood vessels in the brain
(blood-brain barrier).
Keeps certain substances
from moving into the brain.
Helps to direct neurons
during embryo
development and
supplies the neurons with
growth factors. winter2002/gallery.html
Oligodendrocytes and Microglia
 Oligodendrocytes
wrap extension of their
cell membranes around sections of the
axon (myelin sheaths).
Myelin sheaths help to transmit nerve
 Microglia
remove pathogens and cell
debris from the brain.
Ependymal Cells
Lines the ventricles or hollow spaces of the
central nervous system and secretes
cerebrospinal fluid
Cerebrospinal fluid acts as a shock absorber and
helps to carry nutrients to the cells.
Nonneuronal Cells of the
Peripheral Nervous System
Satellite cells protect the cells of the ganglia
 Schwann cells form a myelin sheath around a
segment of an axon. nervous_system.html
Pasternak, Jack J. An Introduction to Human Molecular Genetics: Mechanisms of
Inherited Diseases. Second Edition. John Wiley & Sons, Inc. 2005.
Widmaier, Eric P.; Hershel, Raff; Strang, Kevin T. Vander’s Human Physiology: The
Mechanisms of Body Functions. Tenth Edition. Mcgraw-Hill. 2006.