periaxonal

**Periaxonal**

Periaxonal refers to the region surrounding the axon of a neuron, specifically the myelin sheath’s outer layer. This area is primarily composed of the glial cell processes, such as those from oligodendrocytes in the central nervous system (CNS) or Schwann cells in the peripheral nervous system (PNS). The periaxonal space is a thin gap between the myelin sheath and the axonal membrane, which plays a critical role in maintaining axonal integrity and function.

The periaxonal region is essential for the formation and maintenance of myelin, a fatty substance that insulates axons and facilitates rapid electrical signaling through saltatory conduction. Disruptions in the periaxonal space can lead to demyelinating diseases, such as multiple sclerosis (MS) or Guillain-Barré syndrome, where the immune system attacks myelin, impairing nerve transmission.

Additionally, the periaxonal environment influences axonal health by regulating nutrient supply, ion balance, and signaling molecules. Studies suggest that periaxonal interactions between axons and glial cells also contribute to neuroprotection and repair mechanisms following injury.

Research in this area continues to explore how alterations in the periaxonal space may contribute to neurodegenerative conditions, offering potential targets for therapeutic intervention.