Protection

Protection: The Meninges

Fortunately, a 3-layered membrane called the meninges surrounds the delicate brain.

•Dura mater – most outer layer

•Arachnoid mater – middle layer

•Pia mater – inner layer

Where there are layers, spaces result:

•Potential spaces:

–Epidural space: between skull and dura mater

–Subdural space: between dura mater and arachnoid mater

•Actual space:

–Sub-arachnoid space: between arachnoid mater and pia mater

Protection: Blood-Brain Barrier

•Functions:

–Protects against foreign invaders

–Protects against hormones/neuro-transmitters in rest of body

–Maintains constant environment for brain

Blood-Brain Barrier Problems

 •The following can violate the BBB:

– Hypertension (high blood pressure)

– Developmental problems with BBB

– Hyperosmolality (increased movement of particles)

– Microwaves

– Radiation

– Infection

– Trauma, ischemia, inflammation, pressure