6) Pharmacology - Renal Elimination

Front 1

what are the major mechanisms of renal elimination?

Back 1

(1) glomerular filtration (2) tubular secretion (3) tubular reabsorption (4) storage

Front 2

what is glomerular filtration important for?

Back 2

the small surface area is important for low ER drugs

Front 3

how efficient is glomerular filtration?

Back 3

low efficiency mechanism due to relatively small blood distrubution

Front 4

why is a glomerular filtration a low efficiency mechanism?

Back 4

relatively small blood distribution

Front 5

how much drug is cleared by glomerular filtration?

Back 5

only a small fraction of drugs are cleared by this mechanism

Front 6

what type of drugs undergo glomerular filtration?

Back 6

non-protein bound drugs ONLY; very influenced by binding to plasma proteins because drug bound to protein will not cross glomerulus

Front 7

do protein bound drugs undergo glomerular filtration?

Back 7

No

Front 8

how is renal clearance measured?

Back 8

via glomerular filtration using exogenous (inulin) and endogenous (creatinine)

Front 9

what is inulin and creatinine useful for?

Back 9

to measure renal clearance via glomerular filtration

Front 10

is inulin exogenous or endogenous?

Back 10

exogenous

Front 11

is creatinine exogenous or endogenous?

Back 11

endogenous

Front 12

is inulin or creatinin exogenous?

Back 12

inulin

Front 13

is creatinine or inulin endogenous?

Back 13

creatinine

Front 14

what is tubular secretion important for?

Back 14

high ER drugs

Front 15

describe the clearance of high ER drugs in tubular secretion?

Back 15

Cl approaches renal Q

Front 16

tubular secretion is an active process for what?

Back 16

specific acid/bases

Front 17

is tubular secteion a saturable process?

Back 17

yes

Front 18

there is competition between what in tubular secretion?

Back 18

between weak acids

Front 19

give examples of drugs that are weak acids and compete at tubular secretion?

Back 19

probenecid competes with penicillin and prolongs plasma concentration

Front 20

when does probenecid competes with penicillin and prolongs plasma concentration?

Back 20

as a result of competition between weak acids in tubular secretion

Front 21

Is tubular secretion limited by plasma protein binding?

Back 21

tubular secretion is NOT limited by plasma protein binding because drug has greater affinity for carrier protein in nephraon than plasma protein

Front 22

doesthe drug in tubules have greater affinity for carrier proteins in nephron or for plasm proteins?

Back 22

carrier proteins in the neprhon

Front 23

how is the clearance of a drug altered by tubular secretion?

Back 23

clearance is greater than if it was cleared by filtration alone

Front 24

what type of process is tubular reabsorption?

Back 24

active & passive

Front 25

what is tubular reabsorption affected by?

Back 25

influenced by urine flow rate, drug lipophilicty, pH

Front 26

what part of renal elimination is influence by urine flow rate,drug lipophilicity, and pH?

Back 26

tubular reabsorption

Front 27

what does pH modification affect in tubular reabsorption?

Back 27

certain toxicoses

Front 28

certain toxicoses undergo pH modification where?

Back 28

tubular reabsorption

Front 29

name some toxicoses that undergo pH modification in tubular reabsorption?

Back 29

salicylate, quinidine intoxication

Front 30

salicylate and quinidine intoxication undergo pH modification where?

Back 30

tubular reabsorption

Front 31

how does renal clearance participate in storage?

Back 31

pinocytosis

Front 32

what does pinocytosis cause in renal elimination?

Back 32

prolonged tissue elimination

Front 33

what drug undergoes pinocytosis in the kidney?

Back 33

aminoglycosides such as gentamicin

Front 34

aminoglycosides such as gentamicin under what in the kidney?

Back 34

pinocytosis

Front 35

how is the rate of excretion illustrated in renal elimination?

Back 35

rate of excretion = rate of filtration + rate of secretion - rate of reabsorption

Front 36

what factors influence renal clearance?

Back 36

(1) plasma drug concentration (2) plasma protein binding (3) pH reabsorption

Front 37

plasma drug concentration, plasma protein binding, and pH reabsorption influences what?

Back 37

renal clearance

Front 38

what does plasma drug concentration affect in renal elimination?

Back 38

filtration and reabsorption are not affected while active secretion decreases with increasing plasma concentration

Front 39

is filtration and reabsorption in renal elimination affected by plasma drug concentration?

Back 39

Not affected

Front 40

why is filtration and reabsorption not affected by plasma drug concentration?

Back 40

they are passive processes with rates proportional to plasma concentration and have a linear relationship

Front 41

what is the relationship between filtration/reabsorption and plasma drug concentration?

Back 41

linear

Front 42

is active secretion in renal elimination affected by plasma drug concentration?

Back 42

yes, it decreases with increasing plasma concentration, but we only see this saturation effect with VERY high plasma concentrations

Front 43

what type of relationship does active secretion have with plasma drug concentration in renal elimination?

Back 43

asymptotic relationship, it is saturable with maximum capacity

Front 44

how does plasma protein binding affect renal elimination?

Back 44

it only affects filtration of low ER drugs, not secretion

Front 45

does plasma protein binding affect filtration of low ER drugs or secretion in renal elimination?

Back 45

only affects filtration (low ER drugs), not secretion

Front 46

what factor affects filtrtion of low ER drugs but not secretion?

Back 46

plasma protein binding

Front 47

how does pH reaborption affect weak acids in renal elimination?

Back 47

weak acids are reabsorbed if acidic environment

Front 48

how does pH reabsorption affect weak bases?

Back 48

weak bases are reabsorbed if basic environment

Front 49

how does pH reabsorption affect polar basic drugs?

Back 49

not reabsorbed (Very small)

Front 50

what are pH-sensitive reabsorption drugs dependent on?

Back 50

flow dependence