Cerebrospinal Fluid and Blood Brain Barrier

Question 1

Normal CSF

Answer 1

clear, colorless fluid. Small amount of protein (<25mg/dL). Few lymphocytes (<5 cells

Question 2

Where is CSF produced?

Answer 2

choroid plexus- lateral, third, fourth ventricles

Question 3

CSF

Answer 3

ultrafiltration of blood plasma modified by active transport

Question 4

Rate of production of CSF

Answer 4

constant

Question 5

Circulation of CSF

Answer 5

flows from cranial to caudal.

1. Lateral ventricles
2. third ventricle
3. Mesencephalic aqueduct (cerebral aqeuduct)
4. Fourth Ventricle
5. subarachnoid space via lateral apertures

Question 6

What causes the flow of CSF

Answer 6

pulsation of blood in the choroid plexus

Question 7

Where is CSF absorbed?

Answer 7

arachnoid villi

Question 8

Where is the arachnoid villi

Answer 8

venus sinuses and cerebral veins

Question 9

What impacts the rate of CSF absorption?

Answer 9

CSF pressure

Question 10

Arachnoid Villi

Answer 10

fingerlike inward projection of arachnoid membrane. Single endothelial cell layer. Acts as a one-way valve. CSF flows into the lumen of the sinus but does not allow blood flow into the CSF

Question 11

Functions of CSF

Answer 11

1. Physical protection
2. Pressure Regulation
3. Source of nourishment/waste removal
4. Chemical buffer

Question 12

Hydrocephalus

Answer 12

dilation of the ventricular system. obstruction of CSF flow between site of production and site of absorption

Question 13

Clinical Signs of Hydrocephalus

Answer 13

behavior changes, ataxia, seizures, altered mentation. In young animals, enlarged dome-shaped skull and open fontanelle

Question 14

Treatment of Hydrocephalus

Answer 14

ventriculoperitoneal catheter:
ventricular catheter in brain
valve- pressure or volume regulated
peritoneal catheter into stomach

Question 15

Blood Brain Barrier

Answer 15

selective barrier between systemic circulation and the central nervous sytem.

Question 16

Components of BBB

Answer 16

1. nonfenestrated tight junctions of endothelial cells of the capillary wall
2. endothelial cells surrounded by thick basement membrane
3. layer of foot processes from astrocytes on the surface of the basement membrane

Question 17

Highly Permeable to BBB

Answer 17

water, CO2, O2, and most lipid soluble substances

Question 18

Slightly Permeable to BBB

Answer 18

electrolytes

Question 19

Impermeable to BBB

Answer 19

plasma proteins, most non-lipid soluble, larger organic molecules

Question 20

Areas that Lack BBB

Answer 20

hypothalamus, area postrema, pineal gland

Question 21

Hypothalamus

Answer 21

coordinate autonomic nervous system with pituitary. Sleep and emotional activity

Question 22

Area Postrema

Answer 22

in medulla oblongata, control vomitting

Question 23

Pineal Gland

Answer 23

regulates some hormones. Ex: melatonin