Prostaglandins MCQs With Answer

Prostaglandins MCQs With Answer provide B. Pharm students a focused, application-oriented review of prostaglandin chemistry, biosynthesis, receptors, and pharmacology. This set emphasizes eicosanoid pathways, cyclooxygenase (COX) isoforms, PGE2, PGD2, PGF2α, and thromboxanes, linking molecular synthesis to physiological roles in inflammation, pain, fever, reproduction, and cardiovascular function. Questions cover mechanisms of action, receptor subtypes, synthesis inhibitors, therapeutic targets, and adverse effects of prostaglandin analogs and NSAIDs. Each MCQ reinforces concepts needed for clinical pharmacy, drug development, and exam readiness. Clear explanations will sharpen understanding of prostaglandin metabolism, signaling, and therapeutic manipulation. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which enzyme catalyzes the conversion of arachidonic acid to prostaglandin H2 (PGH2)?

• Cyclooxygenase (COX)
• Lipoxygenase (LOX)
• Prostaglandin synthase
• Thromboxane synthase

Correct Answer: Cyclooxygenase (COX)

Q2. Which enzyme releases arachidonic acid from membrane phospholipids, the first step in prostaglandin synthesis?

• Phospholipase A2
• Phospholipase C
• Acetyltransferase
• Cyclooxygenase

Correct Answer: Phospholipase A2

Q3. Which prostaglandin primarily promotes vasodilation, increases vascular permeability, and mediates fever and pain?

• PGF2α
• PGE2
• PGD2
• TXA2

Correct Answer: PGE2

Q4. Thromboxane A2 (TXA2) is mainly responsible for which physiological effect?

• Bronchodilation and reduced mucus
• Platelet aggregation and vasoconstriction
• Uterine relaxation
• Renal vasodilation

Correct Answer: Platelet aggregation and vasoconstriction

Q5. Aspirin irreversibly inhibits which enzyme to reduce prostaglandin and thromboxane synthesis?

• COX-1 and COX-2 via acetylation
• Phospholipase A2 via phosphorylation
• Thromboxane synthase via methylation
• Prostaglandin dehydrogenase via oxidation

Correct Answer: COX-1 and COX-2 via acetylation

Q6. Selective COX-2 inhibitors were developed to spare which physiological function mediated by COX-1?

• Inflammatory prostaglandin synthesis
• Gastric mucosal protection
• Vasodilation in endothelium
• Renal sodium excretion

Correct Answer: Gastric mucosal protection

Q7. Which prostaglandin analog is commonly used as a topical therapy for glaucoma by increasing uveoscleral outflow?

• Latanoprost
• Misoprostol
• Dinoprostone
• Carboprost

Correct Answer: Latanoprost

Q8. Misoprostol, a PGE1 analog, is clinically used for all EXCEPT:

• Prevention of NSAID-induced gastric ulcers
• Medical termination of pregnancy in combination with mifepristone
• Induction of labor by causing strong uterine contractions
• Treatment of pulmonary arterial hypertension

Correct Answer: Treatment of pulmonary arterial hypertension

Q9. Which prostaglandin is used to maintain patent ductus arteriosus in neonates awaiting corrective surgery?

• Epoprostenol (PGI2)
• Alprostadil (PGE1)
• Dinoprostone (PGE2)
• Latanoprost (PGF2α analog)

Correct Answer: Alprostadil (PGE1)

Q10. Prostacyclin (PGI2) produced by endothelium has which main actions?

• Platelet aggregation and vasoconstriction
• Platelet inhibition and vasodilation
• Bronchoconstriction and sodium retention
• Uterine contraction and cervical ripening

Correct Answer: Platelet inhibition and vasodilation

Q11. Which receptor family do prostaglandin receptors belong to?

• Ionotropic ligand-gated channels
• G-protein-coupled receptors (GPCRs)
• Nuclear hormone receptors
• Receptor tyrosine kinases

Correct Answer: G-protein-coupled receptors (GPCRs)

Q12. Which prostaglandin is most associated with sleep regulation and is abundant in the CNS?’

• PGF2α
• PGE2
• PGD2
• TXA2

Correct Answer: PGD2

Q13. Which laboratory method is commonly used to quantify prostaglandin levels in biological samples?

• Western blotting
• ELISA (enzyme-linked immunosorbent assay)
• Flow cytometry
• Gram staining

Correct Answer: ELISA (enzyme-linked immunosorbent assay)

Q14. Which prostaglandin analog is used intravenously for pulmonary arterial hypertension due to potent pulmonary vasodilation?

• Epoprostenol (PGI2)
• Misoprostol (PGE1)
• Dinoprostone (PGE2)
• Latanoprost (PGF2α analog)

Correct Answer: Epoprostenol (PGI2)

Q15. NSAIDs reduce prostaglandin synthesis primarily by inhibiting which reaction?

• Conversion of PGH2 to PGE2
• Arachidonic acid release from membranes
• Oxygenation of arachidonic acid to PGH2 by COX
• Reduction of prostaglandin transporters

Correct Answer: Oxygenation of arachidonic acid to PGH2 by COX

Q16. Which statement about prostaglandin metabolic inactivation is true?

• They are inactivated mainly by hepatic prostaglandin dehydrogenase and have short half-lives
• They are stable for days in circulation and excreted unchanged
• Renal filtration is their only elimination route
• They are inactivated exclusively in the lungs

Correct Answer: They are inactivated mainly by hepatic prostaglandin dehydrogenase and have short half-lives

Q17. Which prostaglandin receptor subtype mediates most of PGE2’s proinflammatory and pyrogenic effects?

• EP1
• EP2
• EP3
• EP4

Correct Answer: EP4

Q18. Which prostaglandin is used clinically to induce cervical ripening and labor?

• Alprostadil (PGE1)
• Dinoprostone (PGE2)
• Iloprost (PGI2 analog)
• Carboprost (PGF2α analog)

Correct Answer: Dinoprostone (PGE2)

Q19. Carboprost, a PGF2α analog, is primarily used to treat which obstetric condition?

• Prevention of postpartum hemorrhage by uterine contraction
• Maintenance of patent ductus arteriosus
• Prolongation of gestation
• Treatment of gestational diabetes

Correct Answer: Prevention of postpartum hemorrhage by uterine contraction

Q20. Which adverse effect is most associated with systemic prostaglandin analog therapy?

• Hypertension and bradycardia
• Gastrointestinal upset, diarrhea, and abdominal cramping
• Severe hyperglycemia
• Ototoxicity

Correct Answer: Gastrointestinal upset, diarrhea, and abdominal cramping

Q21. Which drug class reduces production of leukotrienes but not prostaglandins by directly blocking 5-lipoxygenase?

• NSAIDs
• Zileuton
• Corticosteroids
• COX-2 inhibitors

Correct Answer: Zileuton

Q22. Why can selective COX-2 inhibitors increase the risk of cardiovascular events?

• They increase TXA2 synthesis in platelets
• They reduce endothelial PGI2 production while sparing platelet TXA2
• They cause hypovolemia and tachycardia
• They directly damage cardiomyocytes

Correct Answer: They reduce endothelial PGI2 production while sparing platelet TXA2

Q23. Which prostaglandin plays a major role in bronchoconstriction during asthma exacerbations?

• PGI2
• PGE2
• PGD2
• TXA2

Correct Answer: PGD2

Q24. Measurement of urinary metabolites of prostaglandins is useful clinically because:

• Urine levels directly measure active circulating prostaglandins
• Prostaglandins are unstable in blood; metabolites in urine reflect systemic synthesis
• Urinary metabolites are not influenced by COX inhibitors
• Urinary assays are faster than plasma assays

Correct Answer: Prostaglandins are unstable in blood; metabolites in urine reflect systemic synthesis

Q25. Which prostaglandin analog is indicated for erectile dysfunction by increasing penile blood flow?

• Alprostadil
• Misoprostol
• Latanoprost
• Epoprostenol

Correct Answer: Alprostadil

Q26. What is the effect of nonselective COX inhibition on platelet function?

• Enhanced platelet aggregation due to increased TXA2
• Reduced platelet aggregation due to decreased TXA2 synthesis
• No effect on platelets because platelets lack COX
• Increased platelet lifespan

Correct Answer: Reduced platelet aggregation due to decreased TXA2 synthesis

Q27. Which prostaglandin is primarily involved in luteolysis and uterine contraction in the reproductive system?

• PGE2
• PGF2α
• PGI2
• PGD2

Correct Answer: PGF2α

Q28. Prostaglandin analogs used in glaucoma can cause which local ocular side effect?

• Conjunctival hyperemia and eyelash growth
• Retinal detachment
• Corneal ulceration
• Acute anterior uveitis in all patients

Correct Answer: Conjunctival hyperemia and eyelash growth

Q29. Which enzyme is the major target of glucocorticoids that leads to decreased prostaglandin synthesis?

• Cyclooxygenase-2 directly
• Phospholipase A2 via induction of lipocortin (annexin-1)
• Prostaglandin dehydrogenase
• Lipoxygenase activation

Correct Answer: Phospholipase A2 via induction of lipocortin (annexin-1)

Q30. Which statement best explains why prostaglandins act locally rather than as typical endocrine hormones?

• They are hydrophilic and bind plasma carriers to act distantly
• They have long plasma half-lives allowing systemic distribution
• They are rapidly metabolized and act near their site of synthesis
• They are stored in secretory granules and released systemically

Correct Answer: They are rapidly metabolized and act near their site of synthesis

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com