Pharmacology - chapter 42 - Autocoids & autocoid antagonists

Question 0

Autacoids are produced by …………….. and act ………………

Answer 0

Autacoids are produced by tissues and act locally

Question 1

Three endogenous compounds that belong to the group of autacoids?

Answer 1

1 prostaglandins
2 histamine
3 serotonin

Question 2

Prostagalndins are derivatives of ……….. ?

Answer 2

unsaturated fatty acids(arachidonic acid)

Question 3

Mifepristone, areas of use?

Answer 3

1 an antiprogestational abortifacient

2 inhibits HCL secretion and enhances mucosal resistance.

Question 4

In what tissues do we find the highest levels of histamine?

Answer 4

sites where the “inside” of the body meets the outside
1 lungs
2 GI tract
3 skin

Question 5

How is histamine synthesized?

Answer 5

by decarboxylation of histidine

Question 6

What factor involving histamine decides whether its release will induce a local allergic reaction or a anaphylactic one?

Answer 6

The rate of secretion. If it’s slow the histamine will be inactivated before it reaches the blood stream. If it’s too fast to be inactivated, a full blown anaphylactic reaction occurs.

Question 7

H1 receptors are associated with?

Answer 7

exocrine glands - inreased mucus production
bronchial smooth muscle - induce bronchial constriction
intestinal smooth muscle - cause cramps and diarrhea
sensory nerve endings - causes itching and pain

Question 8

H1 & H2 receptors are coexpressed in ……….?

Answer 8

1 cardiovascular sytem - positive ionotropism and chronotropism and reduces peripheral resistance.
2 skin - the tripple response: flare, reddening and wheal

Question 9

H2 receptors are expressed?

Answer 9

stomach - stimulates HCL secretion

Question 10

What is the most prominent side effect of first generation antihistamines?

Answer 10

CNS sedation

Question 11

What receptors can H1 antihistamines ineract with?

Answer 11

1 cholinergic receptors
2 alpha-adrenergic
3 serotonin receptors
4 histamin H1 receptors

Question 12

Chlorpheniramine, diphenhydramine, doxylamine, hydroxyzine and promethazine are all ………… ?

Answer 12

first generation antihistamines with marked potential for producing sedation.

Question 13

drugs of choice to treat allergic rhinitis and urticaria?

Answer 13

antihistamines

Question 14

drug of choice to treat systemic anaphylaxis?

Answer 14

epinephrine

Question 15

Antihistamines used in motion sickness?

Answer 15

dimenhydrinate, cyclizine, meclizine, hydroxyzine ++

Question 16

Most antihistamines are metabolized by ……….. ?

Answer 16

P450 system

Question 17

drug interactions related to antihistamines?

Answer 17

potentiation of other CNS depressants, such as alcohol. People who take MAOi should not take antihistamines, as MAOi may exacerbate the cholinergic properties of antihistamines

Question 18

H2 receptor blockers, clinical use?

Answer 18

inhibition of HCL secretion in treatment of ulcers and heartburn

Question 19

What underlying pathomechanism separates migraine with and without aura.

Answer 19

Patients who have migraine without aura do not show hypoperfusion.

Question 20

triptans and dihydroergotamine?

Answer 20

5-ht receptor agonists induce vasoconstriction in the cerebral arteries. Used in treating migraine.

Question 21

Sumatriptan, naratriptan, rizatriptan, almotriptan, frovatriptan, zolmitriptan all work by…..?

Answer 21

acting on a subgroup of serotonin receptors found on small peripheral nerves that innervate intracranial vasculature - producing vsaoconstriction.

Question 22

Agents used in prophylaxis of migraine?

Answer 22

B blockers: propanolol and nadolol
TCA: amitriptyline
Anticonvulsant: Dicalproex
Ca-channel blocker: verpamil

Question 23

What agents are used in the prodromal phase of a migraine attack?

Answer 23

Triptans and dihydroergotamine - vasoconstrictors

Question 24

what are the signs and syptoms of the prodromal phase of a migraine attack?

Answer 24

sensory distrubances, especially visual.

Question 25

Analgesic agents used in the headache phase of a migraine attack?

Answer 25

anti-inflammatory drugs(aspirin, naproxen, ibuprofen). Severe pain may require administration of opioids(e.g. codeine sulfate or merperidine)

Question 26

The major metabolite of Histamine is …?

Answer 26

zoleacetic acid

Question 27

Which protein are H1 and H2 receptors coupled with?

Answer 27

H1 - Gq protein

H2 - Gs protein

Question 28

What is a major problem with the first generation histamine blockers?

Answer 28

Their structure closely resembles muscarinic blockers and alpha adrenoreceptor blockers, producing a wide aray of undesireable adverse effects.

Question 29

Ranitidine, famotidine, nizatidine and cemitidine: clinical application?

Answer 29

H2 antagonist used to lower gastric secretions.

Question 30

Substrate in serotonin synthesis?

Answer 30

tryptophan

Question 31

What is the enzyme responisble for metabolizing serotonin, and what is the major metabolite from this reaction?

Answer 31

MAO degrades serotonin to 5-HIIA(5-hydroxyindoleacetic acid) which can be meassured in the urine.

Question 32

Three types of serotonin receptors, location and associated protein structures?

Answer 32

5-HT1: Gi protein coupled receptor that increase potassium conductance, located primarily in CNS.

5-HT2: Gq protein coupled receptors. Present in CNS & PNS.

5-HT3: cation-gated channel present in CNS, esp. chemoreceptve areas and vomiting center.

Question 33

Clinical application of serotonin and histamine?

Answer 33

None

Question 34

Ergot alkaloids may be classified into three subgroups based on the organ or tissue in which they have their primary effects. These three groups are?

Answer 34

1 Vessels - prolonged alpha mediated vasoconstriction
2 Uterus - produce powerful contraction
3 Brain - some ergots are potent dopamine-like agonists that bind D2 receptors in the pituitary and the basal ganglia.

Question 35

Ergot alkaloids: three areas of clinical use?

Answer 35

1 Migraine
2 Obstetric bleeding
3 Hyperprolactinemia and Parkinsonism

Question 36

Two x adverse effects of cementidine?

Answer 36

1 antiandrogenic effects in some patients

2 significant CYP3A4 inhibiting effects

Question 37

Useful drug for reversing severe ergot-induced vasospasm?

Answer 37

Nitroprusside

Question 38

Two abortifacients?

Answer 38

1 PGF 2alpha

2 PGE2

Question 39

Prostaglandin ued to maintain a patent ductus arteriosus?

Answer 39

PGE1

Question 40

Prostaglandin used in pulmonary hypertension and dialysis?

Answer 40

PGI2 - prostacyclin

Question 41

Major mechanism of the anti-inflammatory effects of corticosteroids?

Answer 41

Inhibition of COX synthesis

Question 42

Zileuton moa?

Answer 42

Inhibits Lipooxygenase

Question 43

drug that have shown to be effective in closing a patent ductus arteriosus in newborns?

Answer 43

Ibuprofen - reversible binding of COX lowers prostaglandin levels, which is responsible for maintianing the duct.