CSF: Body fluid found within the CNS. Fills, circulates through the ventricular system of brain, subarachnoid space and the central canal of spinal cord.

Production:

• Produced by choroid plexuses
  • Network of capillaries, modified ependymal cells in ventricles, also functions as blood-CSF barrier
• Rate: 500mL/day
• Regulated by hormones, blood pressure, autonomic NS

Functions:

• CNS protection
• Trauma: absorbs mechanical energy
• Own weight: provides buoyancy
• Ischaemia: decreases quantity, relieves ICP
• Toxic metabolites: clears
• Transportation medium for chemical signals, nutrients