Neuroglia Types in CNS and PNS

Types of Neuroglia in the Nervous System

Central Nervous System (CNS) Neuroglia

• Astrocytes

  • Function: Support neurons, maintain blood-brain barrier, regulate blood flow, provide nutrients to neurons.
  • Characteristics: Star-shaped; have many processes that extend to blood vessels and neurons.

• Oligodendrocytes

  • Function: Produce myelin sheath that insulates axons, facilitating faster signal transmission.
  • Characteristics: Fewer processes than astrocytes; can myelinate multiple axons.

• Microglia

  • Function: Act as the main immune defense in the CNS; remove waste and dead neurons.
  • Characteristics: Small, with elongated cell bodies and processes; can become activated in response to injury.

• Ependymal Cells

  • Function: Line the ventricles of the brain and the central canal of the spinal cord; produce and circulate cerebrospinal fluid (CSF).
  • Characteristics: Ciliated cells; help in the movement of CSF.

Peripheral Nervous System (PNS) Neuroglia

• Schwann Cells

  • Function: Produce myelin sheath around single axons in the PNS, aiding in signal conduction speed.
  • Characteristics: Wrap around the axon; vital for nerve regeneration.

• Satellite Cells

  • Function: Support and protect neuronal cell bodies in ganglia.
  • Characteristics: Flat cells; regulate the environment around neurons, similar to astrocytes in the CNS.

Summary

• There are four types of neuroglia in the CNS (astrocytes, oligodendrocytes, microglia, ependymal cells) and two types in the PNS (Schwann cells and satellite cells).
• Neuroglia play critical roles in supporting and protecting neurons, ensuring proper function and communication within the nervous system.