Autocoids

Question 1

Eicosanoids are derived from which precursor?

Answer 1

Arachidonic acid

Question 2

Name three main eicosanoids.

Answer 2

Prostaglandins, Thromboxanes, Leukotrienes

Question 3

What enzyme is responsible for liberating arachidonic acid from cell membrane phospholipids?

Answer 3

Phospholipase A (PLA)

Question 4

What are the isoforms of Cyclooxygenase (COX)?

Answer 4

COX-1, COX-2, COX-3

Question 5

Which pathway is responsible for the conversion of arachidonic acid to leukotrienes?

Answer 5

Lipoxygenase pathway

Question 6

What drug is a leukotriene receptor antagonist used in asthma?

Answer 6

Zafirkulast

Question 7

What are the products of the Cyclooxygenase pathway?

Answer 7

Prostaglandins and Thromboxanes

Question 8

Which prostaglandins are vasodilators?

Answer 8

PGI2 (prostacyclin), PGE2

Question 9

Which prostaglandins are vasoconstrictors?

Answer 9

TXA2 (Thromboxane A2), PGF2α

Question 10

What role does PGI2 play in platelet function?

Answer 10

Inhibits platelet aggregation

Question 11

Which drug selectively inhibits COX-2?

Answer 11

Celecoxib

Question 12

Lipoxins are derived from which fatty acid?

Answer 12

Arachidonic acid (ω-6 fatty acid)

Question 13

What is the main role of lipoxins in inflammation?

Answer 13

Resolution of inflammation

Question 14

Which leukotrienes are potent bronchoconstrictors involved in asthma?

Answer 14

LTC4, LTD4, LTE4

Question 15

Which enzyme converts arachidonic acid to leukotrienes?

Answer 15

Lipoxygenase (5-LOASE)

Question 16

Histamine is synthesized from which amino acid?

Answer 16

Histidine

Question 17

Which histamine receptor is involved in allergic responses and vasodilation?

Answer 17

H1 receptor

Question 18

Which histamine receptor is responsible for gastric acid secretion?

Answer 18

H2 receptor

Question 19

Which serotonin receptor is involved in emesis (vomiting)?

Answer 19

5-HT3 receptor

Question 20

What is the role of serotonin in the gastrointestinal tract?

Answer 20

Increases peristaltic movements

Question 21

Which enzyme converts prekallikrein to kallikrein in the kinin system?

Answer 21

Haegeman factor (Factor XII)

Question 22

Which two receptors mediate the effects of kinins?

Answer 22

B1 and B2 receptors

Question 23

Endothelin-1 is primarily secreted by which type of cells?

Answer 23

Vascular endothelium cells

Question 24

Which drug is a non-selective endothelin receptor antagonist used in pulmonary hypertension?

Answer 24

Bosentan

Question 25

Nitric Oxide (NO) is synthesized from which amino acid?

Answer 25

L-arginine

Question 26

What are the three isoforms of Nitric Oxide Synthase (NOS)?

Answer 26

nNOS (neuronal), eNOS (endothelial), iNOS (inducible)

Question 27

What is the main effect of NO on vascular smooth muscles?

Answer 27

Vasodilation

Question 28

Which class of drugs acts as NO donors to induce vasodilation?

Answer 28

Organic nitrates (e.g., nitroprusside)

Question 29

Neurotensin acts as a neuromodulator and has therapeutic potential in which diseases?

Answer 29

Parkinson's disease and schizophrenia

Question 30

What is the primary role of Urotensin II in the body?

Answer 30

Acts as a potent vasoconstrictor