Lecture 6 Flashcards
The Blood Brain Barrier Is a 2 fold entity Between…
- Blood Vessels & Interstitial Fluid
- Blood Vessels & CSF
3 factors of Brain Encasing
- Skull
- Meninges
- Reticular Formation
Blood-Brain Barrier
The endothelial lining of the blood vesicles contain mostly large gaps-
Fenestrations
pores in which molecules can pass
Important features of the endothelial cells in the brain
it contains no pores (this is what makes up the BBB, everything has to be transported)
Meninges
Three layers of membranes known as meninges protect the brain and spinal cord.
3 layers of the meninges (outside-inside)
- Dura Mater
- Arachnoid membrane
- Pia mater
Ventricles
cavities deep inside the brain which are filled with CSF (which is the bathing medium of brain- highly regulated ionic content and few macromolecules)
Cerebral spinal fluid is produced by the ________
choroid plexus (and lines the ventricles)
Arachnoid Villi
an out pouching of the arachnoid tissue
Choroid Plexus
produces most CSF but not all- about 550 ml/day (some CSF is produced in the capillaries inside the brain)
CSF (cerebral-spinal fluid)
- Fills the ventricles and the subarachnoid space
- Has same osmolarity and [Na+] as blood
- LOW [K+], [Ca2+] and [Mg2+]
Astrocytes
provide a bridge between neurons and blood vessels
A Lumbar Puncture
(spinal tap) is a diagnostic, therapeutic procedure to collect a sample of CSF for analysis
2 functions of astrocytes
1) Remove neurotransmitters
2) Provide energy substrates