Transcript 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
volume.
 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.
Astocytes

Star-shaped cell that
provides glucose and
removes ammonia
from the neurons.
 Also regulates
potassium and
neurotransmitters
around synapses.
http://fig.cox.miami.edu/~cmallery/150/neuro/neuroph
ysiology.htm
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.
www.rit.edu/~umagwww/ 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
impulses.
 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.
http://faculty.s
outhwest.tn.e
du/rburkett/A
&P1_nervous
_system_lab.
htm
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.
www.steve.gb.com/science/ nervous_system.html
References
1.
Pasternak, Jack J. An Introduction to Human Molecular Genetics: Mechanisms of
Inherited Diseases. Second Edition. John Wiley & Sons, Inc. 2005.
2.
Widmaier, Eric P.; Hershel, Raff; Strang, Kevin T. Vander’s Human Physiology: The
Mechanisms of Body Functions. Tenth Edition. Mcgraw-Hill. 2006.