Cells of the Nervous System

Cells of the Nervous System

Introduction

• This lecture discusses the cells of the nervous system, including neurons and glial cells.
• Neurons are the primary functional cells, while glial cells provide support.
• A cross-section of the central nervous system reveals neurons and surrounding glial cells.

Neurons

• Neurons are the main functional cells of the nervous system, responsible for executing its functions.
• The main functions of the nervous system are sensation, integration, and response.
• Neurons facilitate communication within the nervous system.
• Neurons make up only about 10% of the cells in the nervous system.
• Neurons have limited regenerative capacity; they cannot easily divide or reproduce.
• Damage to the nervous system tends to be permanent due to the limited regenerative capacity of neurons.
• Neurodegenerative conditions are debilitating due to the irreversible damage to neurons.

Glial Cells (Neuroglia)

• Glial cells, or neuroglia, support neurons and the nervous system.
• "Glia" means "glue," indicating their role in holding the nervous system together.
• Glial cells comprise 90% of the cells in the nervous system.
• They support, nourish, and protect neurons and other structures within the nervous system.
• Glial cells can divide and proliferate, allowing them to replenish themselves if damaged.

Types of Glial Cells

• The lecture will cover the following glial cells:
  • Astrocytes
  • Microglia
  • Satellite cells
  • Ependymal cells
  • Oligodendrocytes
  • Schwann cells
• Some glial cell names change between the central nervous system (brain and spinal cord) and the peripheral nervous system.
• Most glial cells serve supporting, nourishing, and protective roles.