The document discusses the different types of neuroglial cells in the central and peripheral nervous systems. There are four major types of neuroglial cells in the central nervous system: astrocytes, ependymal cells, microglial cells, and oligodendrocytes. Astrocytes provide metabolic support to neurons and help form the blood-brain barrier. Oligodendrocytes myelinate axons to speed signal transmission. The peripheral nervous system contains Schwann cells, which myelinate axons similarly to oligodendrocytes. Neuroglial cells outnumber neurons and provide crucial support roles to ensure neuronal survival.

1. Dr. VINAY PATIDAR
Assist. Professor
R.N. Kapoor Memorial Homoeopathic Hospital &
Medical College, INDORE
TOPIC
“ NEUROGLIA ”

2. CONTENT
 INTRODUCTION
 CHARACTERSTICS OF GLIAL CELLS
 CLASSIFICATION:
1. There are four major types of Central Nervous System (CNS) neuroglial cells:
 Astrocytes
 Ependymal Cells
 Microglial Cells (microglia)
 Oligodendrocytes
2. The Peripheral Nervous System (PNS) contains neuroglial cells:
 Schwann cells

3. INTRODUCTION
Cells that provide metabolic support and immune
protection for neurons.
The neuroglia or Glial cells fill spaces, provide
structural framework, produce myelin, and carry on
phagocytosis.

4. CHARACTERSTICS OF GLIAL CELLS
Neuroglia outnumber neurons by about 10:1 in the
Central Nervous System. Neuroglia do not generate or
conduct nerve impulses. However, unlike neurons,
glial cells can regenerate if injured.
Essentially, since neurons are such specialized cells,
neuroglial cells perform support roles for the neurons
to ensure their survival.
Cells that provide metabolic support and immune
protection for neurons.

5. CLASSIFICATION
 THERE ARE FOUR MAJOR TYPES OF CENTRAL NERVOUS SYSTEM (CNS) NEUROGLIAL CELLS :
 Astrocytes
 Ependymal Cells
 Microglial Cells (microglia)
 Oligodendrocytes

6. ASTROCYTES
STRUCTURE:
 Astrocytes get their name due to the fact that they look
somewhat like a star.
 They have a central cell body surrounded by several
cytoplasmic projections.
 Typically found in the brain.
 The cell body usually sits between a blood capillary and a
neuron of the brain.

7. ASTROCYTES (Cont.)
FUNCTION:
 Function as the blood brain barrier
– Regulate the flow of ions, sugars, oxygen, & carbon dioxide into and out of neurons
– Prevent toxins and poisons from entering brain neurons
 Provide for the energy and other metabolic needs of neurons as well as giving nervous tissue structural support.
 When neurons of the brain or the spinal cord are injured and destroyed, they are replaced with scar tissue made
up of astrocytes (a process called gliosis).

8. EPENDYMAL CELLS
STRUCTURE:
 Usually cube-shaped
 Cells that line the cerebral spinal fluid (CSF) containing cavities of the
brain – the ventricles and the spinal columns central canal.
FUNCTION:
 CSF is secreted by a specialized subset of ependymal cells in the walls
of the ventricles of the brain called the choroid plexus.
 CSF is a Clear liquid that fills internal cavities in the brain and spinal
cord. Ependymal cells have cilia to help circulate CSF.
 It Protects the brain and spinal cord both mechanically and
immunologically.

9. MICROGLIAL CELLS (MICROGLIA)
STRUCTURE:
Smallest of the neuroglial cells.
Able to migrate around the CNS.
FUNCTION:
Phagocytic cells, similar to macrophages, that perform a
housekeeping function by removing dead cellular material and
bacteria from the CNS.

10. OLIGODENDROCYTES
STRUCTURE:
Oligodendrocytes occur in rows along nerve fibers.
They provide insulating layers of myelin around axons within the
brain and spinal cord
Myelin helps to speed up the transmission of electrical signals in
neurons
FUNCTION:
Cells responsible for myelination of axons within the Central
Nervous System.

11.  THE PERIPHERAL NERVOUS SYSTEM (PNS) CONTAINS NEUROGLIAL CELLS:
 Schwann cells
SCHWANN CELLS
The peripheral nervous system contains neuroglial cells as well.
These cells are called Schwann Cells.
Schwann cells form a covering called a Myelin Sheath around
axons.
Basically they perform the same roll as the oligodendrocytes
found in the CNS.