B2W1 Med Phys Cerebral Spinal Fluid Flashcards
Location of CSF Production
Choroid Plexus
Post Circulation of CSF through the Subarachnoid Space occurs where?
Absorbed by Arachnoid Granulation and villi
Where is CSF absorbed into venous blood
Superior Sagittal Sinus
Transcytosis
Method used by the arachnoid granulations to move CSF into venous supply
Choroid Plexus Epithelium Net Ion Secretion to CSF
Na+,Cl-,HCO3-, and H2O
Net ion absorption into the choroid plexus from basolateral membrane
K+
Hydrocephalus
Impaired absorption of the CSF causing accumulation in the meninges
Little to no increase in intracranial pressure
Brain Extracellular Space
Environment outside of the brain in which the CSF exchanges waste with important molecules to maintain the neuronal environment
Blood Brain Barrier
Continuous Tight Junctions that prevent certain molecules from entering the brains blood supply
Areas that lack a BBB
Median Eminence
Area Postrema
Subfornical Organ
Subcommissural Organ
Pineal Gland
OVLT
Posterior Pituitary
MASSPOP
Glial Cells Central Nervous System
Astrocytes
Oligodendrocytes
Microglial Cells
Glial Cells Peripheral Nervous System
Satellite Cells
Schwann Cells
Enteric Glia
Astrocyte Function
Supply fuel to neurons, stores glycogen, regulate K+, secrete trophic factors, communicate via gap junctions, and modulate cerebral blood flow
Glutamate-Glutamate Synthesis
Glutamate enters astrocyte -> reacts with Glutamine Synthetase to make Glutamine -> Glutamine is co-transported with sodium through a SNAT3 and SNAT5 channel pumped by internal hydrogen -> Glutamine enters presynaptic cell through a sodium glutamine transporter -> Glutaminase changes glutamine back into glutamate -> Glutamate undergoes exocytosis out of the cell and enters the synaptic cleft -> From the cleft Glutamate enters the cell along with Na+ K+ and H+ via EAAT1 and EAAT2 channels into the astrocyte or back into the presynaptic terminal via EAAT3
Oligodendrocytes
Produce Myelin within the CNS
1 Oligodendrocyte to many neurons
