Lecture 5

Question 1

3 main forms of excretion

Answer 1

fecal
urinary
expired air

Question 2

why is biotransformation necessary

Answer 2

bc most drugs are lipid soluble, weak organic acids or bases and are not readily eliminated - need to be converted to something more water soluble to be eliminated

Question 3

the outcome of biotransformation is the facilitation of _____

Answer 3

excretion

Question 4

3 main sites of drug metabolism

Answer 4

liver
kidney
skim

Question 5

name 4 polar functional groups that can be introduced in phase 1 reactions

Answer 5

OH
SH
NH2
COOH

Question 6

phase 1 reactions result in _____ molecular weight change

Answer 6

SMALL

Question 7

phase 2 reactions are __________ reactions

Answer 7

conjugation

Question 8

with the exception of ____ and ____, phase 2 reactions result in a large increase in hydrophilicity

Answer 8

acetylation and methylation

Question 9

phase 2 biotransformation can result in both ____ and ____ of xenobiotics

Answer 9

detoxification and activation

Question 10

phase 1 is ______ and phase 2 is _____

Answer 10

phase 1 is microsomal and phase 2 is cytosolic

Question 11

2 things involved with GSH conjugation

Answer 11

GST (glutathione transferase) and GSH (glutathione)

Question 12

enzyme and cofactor involved with sulfation

Answer 12

enzyme = sulfotransferase

cofactor = PAPS

Question 13

enzyme and cofactor for glucuronidation

Answer 13

enzyme = UDP-GT

cofactor = UDP-GA

Question 14

acetylation enzyme and cofactor

Answer 14

acetyltransferase

cofactor = acetyl coenzyme A

Question 15

cofactor and enzyme for methylation

Answer 15

cofactor = SAM

enzyme = methyltransferase

Question 16

acetaminophen uses what 2 phase 2 pathways

Answer 16

glucuronidation and sulfation

Question 17

glucuronidation (phase 2) does not reach adult values unitl….

Answer 17

3-6 months of life

Question 18

antibiotics excreted through the _______ should be used in caution in newborns

Answer 18

liver

Question 19

most used enzyme in phase 1

Answer 19

CYP450 system

Question 20

the highest concentration of CYP450 enzymes are found where?

Answer 20

in microsomes of the liver endoplasmic reticulum

(but they are present in all tissues)

Question 21

what other organelle (besides microsomes) are CYP450 enzymes found

Answer 21

mitochondria

Question 22

all CYP450 enzymes are _____-containing proteins

Answer 22

heme

Question 23

the human genome encodes at least ______ P450s and ___ pseduogenes

Answer 23

57 P450s and 29 pseduogenes

Question 24

SOD

Answer 24

superoxide dismutase

detoxifies superoxide so it doesn’t affect our cells

Question 25

3 isoforms of superoxide dismutase and where they're located

Answer 25

CuZnSOD (cytoplasm) MnSOD (mitochondria) ECSOD (cytoplasm)

Question 26

most reactive ROS

Answer 26

hydroxy radical

Question 27

how is H2O2 toxic

Answer 27

oxidizes lipids in the lipid membrane

Question 28

3 major organs involved in biotransformation

Answer 28

liver kidney skin

Question 29

what is the name for the "stem cells of the airways"

Answer 29

clara cells

Question 30

what enzyme converts H2O2 to water

Answer 30

catalase

Question 31

steps of alcohol metabolism

Answer 31

alcohol to aldehyde by alcohol dehydrogenase aldehyde to carboxylic acid by aldehyde dehydrogenase

Question 32

what CYP is also involved in alcohol metabolism

Answer 32

CYP2E1

Question 33

where is catalase located

Answer 33

peroxisomes

Question 34

where is ADH (alcohol dehydrogeanse) located

Answer 34

cytosol

Question 35

where is CYP2E1 located

Answer 35

microsomes