The lining ependyma of each ventricle comes into contact with the surface pia mater allowing the invagination of a mass of blood capillaries --- combination of these capillaries , pia and ependyma constitutes the choroid plexus .
Collectively, the blood vessels within the brain have a very large surface area that promotes the exchange of oxygen, carbon dioxide, amino acids, and sugars between blood and brain.
The blood-CSF barrier is formed by active transport from the blood vessels to the brain- Epithelial cells of joined by tight junctions, form a continuous layer that selectively permits the passage of some substances but not others.
corpora amylacea --- calcify ---- after the age of forty years they normally throw a shadow in radiographs of the skull
displaced calcified pineal indicates a space-occupying lesion above the tentorium
melatonin (a hormone related to serotonin), which in animals and probably in man also has an antigonadotrophic action.
part of the tuber cinereum at the base of the infundibulum is the median eminence — highly important as the site of the neurosecretory cells that control the anterior pituitary, and one of the few regions with no blood/brain barrier