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Neuropsychopharmacology > Delivering Drugs to the CNS > Flashcards

Flashcards in Delivering Drugs to the CNS Deck (14)
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1
Q

What does Kp indicate?

A

the ratio between drug in the blood and drug in the brain

2
Q

What does a Kp > 1 indicate?

A

A higher concentration in the brain than the blood

3
Q

How can drugs move between body compartments?

A

transcellular

paracellular

4
Q

How can the rate that a compound crosses the membrane be measured?

A

Passive permeability using artificial membranes PAMPA

Or MDCK

5
Q

What is the free-drug hypothesis?

A

Pharmacological activity is dependent on free drug availability

6
Q

What affects the free drug?

A

the amount bound to protein and the amount unbound from protein

7
Q

What is fractional binding affected by?

A

protein - NOT drug

8
Q

How is fractional binding calculated?

A

protein/protein+affinity

9
Q

What is Kp u,u?

A

the ratio of unbound drug concentrations in the brain and the blood

10
Q

What is occurring if Kp is something other than =1?

A

more than passive diffusion

11
Q

What is the blood brain barrier made up of?

A

endothelial cells, astrocytes, pericytes

12
Q

What is the function of the blood brain barrier?

A

allows distribution of v. small molecules
prevents ionic flux that might affect neuronal function
provides selective uptake mechanism for required molecules
provide protected environment for CNS

13
Q

What is P-gp?

A

transporter that actively pumps molecules back out to prevent transcellular permeation

14
Q

Where is P-gp found?

A

only on the apical side of the cell