Pharm of vasoactive peptides

Question 1

What are the 5 vasoactive peptides?

Answer 1

1) angiotensin (I, II, III)
2) kinins (bradykinin)
3) endothelins
4) vasopressin
5) ANP

Question 2

True or false: all vasoactive peptides act on cell surface receptors

Answer 2

TRUE (mostly via GPCRs)

Question 3

True or false: angiotensin II is the only active form of AT that produces profound vasoconstriction

Answer 3

true

Question 4

What enzyme converts angtiotensinogen to angtiotensin I

Answer 4

renin

Question 5

What enzyme converts angiotensin I to angiotensin II?

Answer 5

ACE

angiotensin converting enzyme

Question 6

Which drugs are known to produce an increase in angiotensin?

Answer 6

corticosteroids
estrogens
thyroid hormones
angiotensin II

Question 7

AT I is a decapeptide while ATII is a ____________

Answer 7

octapeptide

Question 8

What are 2 other names for ACE?

Answer 8

peptidyl dipeptidase

kininase II

Question 9

Where is ACE found?

Answer 9

widely distributed in the vasculature on the luminal structure of the endothelial cells

Question 10

What enzyme hydrolyzes ATII to ATIII?

Answer 10

angiotensinase

Question 11

What is the danger of too much ATII production?

Answer 11

hypertension

Question 12

True or false: ATII promotes the release of epi and nor epi from adrenal medulla

Answer 12

true

Question 13

What 3 parts of angiotensin pathway are targeted by drugs?

Answer 13

1) renin secretion
2) converstion of ATI to ATII
3) block AT receptors

Question 14

In addition of blocking the conversion of ATI to ATII, what else do ACE inhibitors do?

Answer 14

inhibit degradation of bradykinins (as well as substance P and enkephalin)

Question 15

Why do you see hypotensive effects after treatment with ACE inhibitors/

Answer 15

because ACE inhibitors inhibit the degradation of bradykinins

Question 16

What are the orally active ACE inhibitors?

Answer 16

captopril

enalapril

Question 17

What is the chemistry behind angiotensin receptor blockers?

Answer 17

substitution of sarcosine for phenylalanine in position 8 of ATII

Question 18

What class does saralasin belong to?

Answer 18

peptide ARBs

angiotensin receptor blockers

Question 19

What are the nonapeptide ARBs?

Answer 19

losartan

valsartan

Question 20

What enzymes produce kinins?

Answer 20

kallikreins (kininogenases)

Question 21

True or false: kinins can be generated by insect bites

Answer 21

true

Question 22

What enzyme converts plasma prekallikrein to plasma kallikrein?

Answer 22

trypsin
kallikrein
hageman factor (factor XIIa)

Question 23

kallikrein converts __________ to __________

Answer 23

kininogen to bradykinin

Question 24

Where are kallikreins made?

Answer 24

liver

Question 25

Where are kallikreins present?

Answer 25

``` plasma kideny pancreas GI tract sweat glands salivary glands ```

Question 26

What is Fletcher factor?

Answer 26

plasmatic prekallikrein promotes coag process via intrinsic system

Question 27

Why do DIC patients develop hypotension?

Answer 27

increased kallikrein production

Question 28

What are kininogens?

Answer 28

substrates for kallikreins

Question 29

What 2 varieties of kininogens are there?

Answer 29

low molecular weight | high molecular weight

Question 30

plasma kallilkrein cleaves ________ to generate bradykinin

Answer 30

HMW kininogen (high molec weight)

Question 31

What are the 3 kinds of kinins?

Answer 31

1) bradykinin 2) lysyl bradykinin 3) meth-lysylbradykinin

Question 32

Bradykinin is released by ________ __________

Answer 32

plasma kallikrein

Question 33

lysyl bradykinin is released by __________ ________

Answer 33

glandular kallikrein

Question 34

meth-lysylbradykinin is released by _______

Answer 34

pepsin

Question 35

Where in the body are the 3 kinins found

Answer 35

plasma | urine

Question 36

True or false: kinins stimulate the release of NO

Answer 36

true

Question 37

What are the 2 types of kinin receptors?

Answer 37

``` B1 = predominant receptors B2 = targeted by drugs ```

Question 38

What is another name for kininase II?

Answer 38

ACE (can also inactivate bradykinin)

Question 39

What does icatibant target?

Answer 39

second generation B2 receptor inhibitor (treat hypotension)

Question 40

How do ACE inhibitors affect bradykinin?

Answer 40

augment its effects by blocking the degradation of it

Question 41

How does aspirin affect the kallikrein kinin system?

Answer 41

blocks the algesic effects of prostaglandins

Question 42

What are the effects of vasopressin

Answer 42

increased blood pressure (short term vasoconstrictor actions)

Question 43

What is the clinically used analogue of vasopressin?

Answer 43

desmopressin

Question 44

What is the effect of desmopressin?

Answer 44

increases factor 8 activity and von willebrand factor

Question 45

What do the drugs omapatrilat, sampartilat, and fasidotrilat do?

Answer 45

enhance vasodilation, reduce vasoconstriction, and increase sodium excretion (via increasing levels of natriuretic peptides)

Question 46

What do the endothelins do?

Answer 46

vasoCONSTRICT

Question 47

What are the 2 receptors for endothelin actions?

Answer 47

ETa and ETb

Question 48

What is Bosentan?

Answer 48

a non selective antagonist of endothelin (treats pulm hypertension)

Question 49

What is VIP?

Answer 49

vasodilator made in nervous system

Question 50

What is substance P?

Answer 50

vasodilator (releases NO by upregulating iNOS)

Question 51

What is neurotensin

Answer 51

vasodilator

Question 52

Where is calcitonin gene related peptide found?

Answer 52

thyroid gland, CNS, GI

Question 53

What is adrenomodulin?

Answer 53

increases in exercise, hypertension, renal failure, septic shock vasodilator

Question 54

What is neuropeptide Y?

Answer 54

vasoconstrictor

Question 55

What is urotensin?

Answer 55

vasoconstrictor (increases with end stage heart failure)

Question 56

When patients are treated with ACE inhibitors for hypertension, why might they go into shock?

Answer 56

excessive generation of bradykinin