How is CSF produced?

  • Produced by the four choroid plexuses:
    • Located in the two lateral, third, and fourth ventricles
    • Highly vascular invaginations of pia mater
    • Covered by specialised ciliated ependymal cells
Location of the choroid plexuses
  • Produced by a combination of:
    • Filtration of plasma through the fenestrated capillaries
    • Active transport of solutes
  • Control of substances entering is regulated by the blood-CSF barrier (distinct from the BBB)
Structure of the choroid plexus