Week 3 (Quiz 3) (Antihistimine)

Question 1

Histamine is a neurotransmitter implicated in: (3 things)

Answer 1

1) immediate hypersensitivity rxns
2) bronchospasm
3) gastric acid secretion

Question 2

Histamine is in ____ tissues

Answer 2

all (esp. GI, lungs, skin)

Question 3

Histamine is complexed to ___ inside _____ in inactive form

Answer 3

heparin, mast cell/basophil granules

Question 4

Histidine –> histamine (enzyme)

Answer 4

histidine decarboxylase

Question 5

Mast cell degranulation is triggered by:

Answer 5

1. Binding of allergens
2. bacterial toxins/insect stings
3. trauma/cold

Question 6

Autocids

Answer 6

biologically active substances; short half-life; act near site of synthesis

Question 7

Two types of autocids

Answer 7

1. vasoactive amines

2. eicosanoids

Question 8

Vasoactive amines, What and released by?

Answer 8

Histamine, 5-HT

Released by mast cells and basophils; platelets

Question 9

Eicosanoids, What and released by?

Answer 9

Prostaglandins, leukotrienes

Released by all leukocytes, platelets

Question 10

H1 receptor G protein

Answer 10

Gq

Question 11

H1 impact on IP3 and DAG

Answer 11

increased

Question 12

Peripheral effects of H1 activation

Answer 12

• increased naso/broncho mucous production
• bronchoconstriction
• pruritis (itching/pain)
• inflammation (rubor, tumor, dolor)

Question 13

CNS effects of H1 activation

Answer 13

• Increased BP
• Increased HR
• Super increased neurotransmission/cognitive and psychomotor performance
• Super decreased sedation

Question 14

H2 G protein

Answer 14

Gs

Question 15

H2 activation impact on cAMP

Answer 15

increased cAMP

Question 16

H2 activation effect in peripheral and CNS

Answer 16

• increased gastric acid secretion
• decreased BP
• increased HR
• Inflammation (rubor, tumor, dolor)

Question 17

H3 G protein

Answer 17

Gi

Question 18

H3 activation impact on cAMP

Answer 18

decreased cAMP

Question 19

H3 peripheral and CNS activation impact

Answer 19

presynaptic inhibition of CNS neurotransmitter release

Question 20

H4 G protein

Answer 20

Gi

Question 21

H4 activation impact on cAMP

Answer 21

decreased cAMP

Question 22

H4 impact

Answer 22

mast cell chemotaxis

Question 23

Diphenhydramine; chorpheniramine; dimenhydrinate; doxylamine

What type of antagonist? What generation

Answer 23

1st Generation H1 Antagonist

Question 24

Mechanism of G1 H1 antagonists?

Answer 24

competitive, reversible inhibition of H1 receptors in PNS and CNS –> ↓ DAG/IP3

Question 25

Effects of G1 and G2 H1 antagonists on: mucous production bronchoconstriction itching

Answer 25

Decreased

Question 26

Effects of G1 H1 antagonists on: Sedation NT release

Answer 26

Increased, decreased

Question 27

SE of G1 H1 antagonists

Answer 27

strong SEDATION; low selectivity - also blocks muscarinics, α- adrenergics, 5-HT (sympathetic effects; hypotension/dizziness; tachycardia; increased appetite)

Question 28

Use of G1 H1 antagonists

Answer 28

- allergic conditions - motion sickness/nausea - sleep aid

Question 29

cetirizine; loratidine; fexofenadine What type of antagonist? What generation?

Answer 29

2nd Generation H1 antagonist

Question 30

Mechanism of G2 H1 antagonist?

Answer 30

competitive, reversible inhibition of H1 receptors in PERIPHERY only (do not cross BBB)

Question 31

SE of G2 H1 antagonists?

Answer 31

less than 1st gen due to greater specificity and no CNS effects

Question 32

Use for G2 H1 antagonists?

Answer 32

allergic conditions (hay fever, urticaria, contact dermatitis, angioedema, itching)

Question 33

Cimetidine; ranitidine; famotidine; nizatidine What type of antagonist? What generation?

Answer 33

H2 antagonist

Question 34

Mechanism for H2 antagonist

Answer 34

competitive, reversible inhibition of H2 receptors --> ↓ cAMP

Question 35

Effects of H2 antagonist

Answer 35

↓ gastric acid secretion

Question 36

SE of H2 antagonist

Answer 36

anti-androgenic effects (prolactin release, impotence, gynecomastia in males);

Question 37

Use of H2 antagonists

Answer 37

peptic ulcer disease; gastric esophageal reflux; gastritis

Question 38

Steroids block:

Answer 38

phospholipase A2 and Cox-2

Question 39

NSAIDS block

Answer 39

Cyclooxygenases (COX-1 and COX-2)

Question 40

What do prostaglandins do in general at physiologic levels?

Answer 40

- maintenance of gastric mucous secretion - control renal blood flow - platelet aggregation

Question 41

What do prostaglandins do in general at inflammatory levels?

Answer 41

- increased pain sensation - increased body temp - vasodilation

Question 42

Leukotrienes in general:

Answer 42

increase bronchoconstriction

Question 43

Which enzyme creates leukotrienes from arachidonic acid?

Answer 43

5-lipoxygenase

Question 44

Which enzymes create prostaglandins from arachidonic acid?

Answer 44

COX-1 and COX-2

Question 45

What enzyme creates arachidonic acid from membrane phospholipids?

Answer 45

Phospholipase A2