exam 3 distribution

Question 1

what does the con vs time graph look like when a drug rapidly distributes into highly perfused tissues and is restricted to these tissues

Answer 1

highest con at first then decreases, negative slope

Question 2

what does the con vs time graph look like when a drug distributes into tissues at different rates

Answer 2

plasma downward curve slope, tissue up until plasma line then peak and downward- it moves out of the plasma into the tissue

Question 3

if a drug readily crosses membranes and is widely distributed throughout the body, differences in tissue perfusion rate result in

Answer 3

different time courses for drug in tissues

Question 4

what are the organs with high perfusion rate

Answer 4

lung, kidney and liver

Question 5

perfusion rate limited is when a drug goes from the blood to the tissue and passes

Answer 5

immediatly

Question 6

permeability rate limited is then a drug goes from the blood to the tissue and passes

Answer 6

a membrane barrier

Question 7

will perfusion or permeability rate limited slow tissue distribution

Answer 7

permeability

Question 8

transvascular transport includes convection and diffusion, what are each lead by

Answer 8

convection- pressure
diffusion- concentration

Question 9

what method of transvascular transport is likely to be important for monoclonal antibodies

Answer 9

convection

Question 10

what happens as pressure increases in convection

Answer 10

the gaps get bigger and pushes bigger molecules through

Question 11

what happens when a drug binds to a plasma protein or RBC

Answer 11

it restricts distribution by only allowing the free drug to pass the membrane

Question 12

in tissues drugs bind to ___ __ not receptors

Answer 12

nonspecific sites

Question 13

a lipid soluble drug can pass what 3 barriers

Answer 13

epithelial barrier, capillary endothelium and cellular membrane

Question 14

a water soluble drug only passes what 2 barriers

Answer 14

epithelial barrier and capillary endothelium

Question 15

as adverse effects increase, binding ___

Answer 15

decreases

Question 16

T/F weak base is unionized and can cross the membrane

Answer 16

true

Question 17

once the unionized drug passes the membrane it becomes

Answer 17

ionized and cannot cross the membrane

Question 18

what is it called when the ionized drug cannot cross the membrane

Answer 18

trapping

Question 19

what are the blood brain barrier characteristics that make it hard to pass

Answer 19

tight junctions, negative head groups and high concentration of Pgp

Question 20

what does tight junctions mean

Answer 20

almost no paracellular permeation

Question 21

what does negative head groups mean

Answer 21

limited diffusion for acids

Question 22

what does high concentration of Pgp mean

Answer 22

high efflux activity, even compounds that get in are pumped right out

Question 23

the arachnoid cells have

Answer 23

tight junctions

Question 24

the CSF, plasma, interstitial fluid and the intracellular fluid all have around what pH

Answer 24

7-7.4

Question 25

the lysosome has what pH

Answer 25

5

Question 26

what may cause the drug to gain entry to the CNS

Answer 26

appropriate phytochemical properties, using an existing transporter, disrupting the BB and direct administration into the CNS

Question 27

what are some things that might disrupt the BBB

Answer 27

microwaves, radiation, trauma, hypertension, infection

Question 28

what is the risk with disrupting the BBB

Answer 28

other things can pass and get in that are not suppose to be in the brain

Question 29

what do focused ultrasounds do

Answer 29

it vibrates the BBB with the micro-bubbles that were injected and opens some small gaps to allow small molecules to get in

Question 30

the pH is lower in the fetal tissue which will allow some drugs to

Answer 30

get trapped