Cerebrospinal Fluid
(CSF)
,• CSF is present in the subarachnoid space, ventricles and central canal.
• Total amount of CSF in the subarachnoid space is 150 ml.
• The rate of formation is about 500 ml per day. (20 ml/hour).
• Composition of CSF resembles that of plasma or ECF.
• PH of CSF is 7.35. specific gravity is 1.005
• CSF is transparent colorless fluid.
• Formation of CSF involves ultrafiltration because proteins are not filtered.
, Formation of CSF
50-70 % of CSF is formed from choroid plexus.
|
Choroid plexus project into lateral horn , third ventricle and the roof of 4th ventric
|
Formation of CSF mainly involves active transport. There may be facilitated or sim
diffusion.
|
Formation of CSF starts with the active transport of sodium. There is NaK Atpase p
the lining of choroid plexus.
|
When sodium is transported actively there is secondary active transport of chlorid
followed by osmosis of water. Glucose if transported by carrier mediated diffusion
brain barrier is permeable to CO2. Co2 binds with water to form carbonic acid wh
dissociates into bicarbonate and hydrogen ions. this reaction is catalyzed by carbo
anhydrase.
(CSF)
,• CSF is present in the subarachnoid space, ventricles and central canal.
• Total amount of CSF in the subarachnoid space is 150 ml.
• The rate of formation is about 500 ml per day. (20 ml/hour).
• Composition of CSF resembles that of plasma or ECF.
• PH of CSF is 7.35. specific gravity is 1.005
• CSF is transparent colorless fluid.
• Formation of CSF involves ultrafiltration because proteins are not filtered.
, Formation of CSF
50-70 % of CSF is formed from choroid plexus.
|
Choroid plexus project into lateral horn , third ventricle and the roof of 4th ventric
|
Formation of CSF mainly involves active transport. There may be facilitated or sim
diffusion.
|
Formation of CSF starts with the active transport of sodium. There is NaK Atpase p
the lining of choroid plexus.
|
When sodium is transported actively there is secondary active transport of chlorid
followed by osmosis of water. Glucose if transported by carrier mediated diffusion
brain barrier is permeable to CO2. Co2 binds with water to form carbonic acid wh
dissociates into bicarbonate and hydrogen ions. this reaction is catalyzed by carbo
anhydrase.
