Blood Brain Barrier & Csf Kretzer Lecture

Front 1

Astrocytes induce....

Back 1

tight junctions, modifications of vesicular transport, unidirectional active transport of mitochondria; blood brain barrier, synapse formation, NT uptake

funnel function

Front 2

Carrier mediated transporters are unique in that they

Back 2

Only allow uptake of glucose from plasma into neuropil, L amino acids, only has carrier mediated transport for essential amino acid that neuropil cannot make

Front 3

Difference between morphine and heroine

Back 3

morphine has two hydroxyl groups, heroine has none so it has greater lipid solubility

Front 4

15% of grey and white matter

Back 4

extracellular space

Front 5

Function of CSF

Back 5

gives brain buoyant density bc it floats in the CSF fluid in the ventricles; prevents brain from banging into the bones, purge of the neuropil system to get rid of waste products, micronutrients of the brain (vit c, folates, prealbumin to carry thyroid hormone, growth factors)

Front 6

Choroid plexus

Back 6

loose CT with leaky capillary bed giving a randomized transudate that will become CSF; epithelium of choroid plexus (which has massive apical microvilli) = neural crest origin

Front 7

Epithelium of choroid plexus

Back 7

has bidirectional active transport to secrete micronutrients into the CSF, and purge impurities from the CSF

Front 8

Ependymal cells

Back 8

no tight junctions, gross nutrition (essential amino acids, glucose), many cilia , highly modified astrocytes

Front 9

Funciton of capillary beds in neuropil in BBB

Back 9

micronutrients like vitamin C, folates, prealbumin to bind

Front 10

Aging causes atrophy of the choroid plexus

Back 10

less micronutrients, less prealbumin --> dementia

Front 11

Functions of the blood brain barrier

Back 11

keep plasma toxins out of neuropil ; prevent plasma vascilations of ions from impacting on the neuropil; exclude all circulating NTs; halt plasma growth factors and plasma proteins from entering neuropil, keep neuropil NTs within confined space

Front 12

unique transport channels only for

Back 12

L amino aicds, D-glucose, essential AAs that neuropil cannot synthesize

Front 13

astrocytes have funnel function to...

Back 13

dump waste products around basal surface of the endothelial cells which are then actively transported OUT of the neuropil

Front 14

mannitol bolus injection of Rapoport

Back 14

unravel tight junctions of the BBB; mannitol (low penetrance into neuropil, acts as a spectacular hyperosmolar solute to dehydrate the endothelial cells)

Front 15

if a substance enters at a rate less than is hydrophobicity...

Back 15

it is bound to albumin (phenobarbital and phenytoin)

Front 16

CSF sites

Back 16

ventricles of the brain, central canal of spinal cord, subarachnoid space, along spinal column

Front 17

CSF properties

Back 17

colorless
low in glucose,
slightly more acidic than plasma (ph 7.33)

Front 18

Flow of CSF

Back 18

lateral ventricles --> two interventricular foramina of Monro --> 3rd ventricle --> cerebral aqueduct of Sylvius --> 4th ventricle --> 2 lateral foramina of Lushka and medial foramen of Magendie --> subarachnoide spaces --> arachnoid granulations --> superior sagittal sinus --> jugular vein

Front 19

four purges of the neuropil

Back 19

active transport across BBB endothelial cells into lumen

funnel function of astrocytes
active transport across epithelium of choroid plexus into loose CT
equilibrium of the ECF and the CSF across pia and ependymal cells