Mediators of inflammation MCQs With Answer

Mediators of inflammation MCQs With Answer provide B. Pharm students a focused, exam-ready review of key inflammatory pathways, cellular sources, and pharmacological targets. This concise guide covers histamine, prostaglandins, leukotrienes, cytokines (TNF, IL-1), complement fragments, nitric oxide, kinins and specialized pro-resolving mediators, with emphasis on biosynthesis, receptors, and drug interactions. Ideal for pharmacology, pathology and therapeutics revision, these MCQs highlight mechanisms of action, enzyme inhibitors (COX, LOX), anti-inflammatory drugs (NSAIDs, corticosteroids, biologics) and clinical implications. Practice these targeted questions to strengthen concepts, improve recall and prepare for university exams and competitive tests. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. Which cell is the primary source of histamine during the immediate phase of acute inflammation?

• Mast cells
• Macrophages
• Endothelial cells
• Neutrophils

Correct Answer: Mast cells

Q2. Which enzyme catalyzes the conversion of arachidonic acid to prostaglandin H2, the precursor of many prostaglandins?

• 5-Lipoxygenase
• Cyclooxygenase (COX)
• Phospholipase A2
• Thromboxane synthase

Correct Answer: Cyclooxygenase (COX)

Q3. Which mediator is most responsible for vasodilation and increased vascular permeability via nitric oxide (NO) production?

• Leukotriene B4
• Prostaglandin E2
• Bradykinin
• Nitric oxide itself synthesized by iNOS

Correct Answer: Nitric oxide itself synthesized by iNOS

Q4. Leukotriene B4 (LTB4) primarily functions as:

• A vasoconstrictor
• A chemotactic factor for neutrophils
• An anticoagulant
• A platelet aggregation inhibitor

Correct Answer: A chemotactic factor for neutrophils

Q5. Which complement fragment is a potent chemoattractant and activator of neutrophils?

• C3b
• C5a
• Factor B
• C1q

Correct Answer: C5a

Q6. Bradykinin primarily produces which of the following effects?

• Promotion of platelet aggregation
• Vasodilation, pain, and increased vascular permeability
• Inhibition of neutrophil chemotaxis
• Direct microbial killing

Correct Answer: Vasodilation, pain, and increased vascular permeability

Q7. Which of the following is a major product of the 5-lipoxygenase pathway?

• Prostaglandin I2 (prostacyclin)
• Leukotrienes (e.g., LTB4, LTC4)
• Thromboxane A2
• Prostaglandin D2

Correct Answer: Leukotrienes (e.g., LTB4, LTC4)

Q8. Which prostaglandin is chiefly responsible for fever generation in the hypothalamus?

• Prostaglandin F2α
• Thromboxane A2
• Prostaglandin E2 (PGE2)
• Prostacyclin (PGI2)

Correct Answer: Prostaglandin E2 (PGE2)

Q9. Which drug irreversibly inhibits COX-1 and COX-2 by acetylation of the enzyme?

• Ibuprofen
• Aspirin
• Acetaminophen (paracetamol)
• Naproxen

Correct Answer: Aspirin

Q10. Which mediator is released from platelets and causes vasoconstriction and platelet aggregation?

• Thromboxane A2 (TXA2)
• Prostaglandin E2
• Nitric oxide
• Bradykinin

Correct Answer: Thromboxane A2 (TXA2)

Q11. Which cell surface molecules on leukocytes mediate the initial rolling along the endothelium?

• Integrins
• Selectins
• Immunoglobulins
• Cadherins

Correct Answer: Selectins

Q12. Which mediator family includes lipoxins, resolvins and protectins that promote resolution of inflammation?

• Eicosanoids derived from cyclooxygenase
• Reactive oxygen species
• Specialized pro-resolving mediators (SPMs)
• Complement components

Correct Answer: Specialized pro-resolving mediators (SPMs)

Q13. Which cytokine is a key mediator of systemic acute-phase response and can induce fever and hepatic acute-phase protein synthesis?

• Interleukin-10 (IL-10)
• Interleukin-1 (IL-1)
• Interferon-gamma (IFN-γ)
• Transforming growth factor-beta (TGF-β)

Correct Answer: Interleukin-1 (IL-1)

Q14. Which enzyme releases arachidonic acid from membrane phospholipids as the first step in eicosanoid synthesis?

• Cyclooxygenase (COX)
• Phospholipase A2 (PLA2)
• 5-Lipoxygenase
• Thromboxane synthase

Correct Answer: Phospholipase A2 (PLA2)

Q15. Which leukocyte-derived mediator directly increases vascular permeability by causing endothelial cell contraction and widening of intercellular gaps?

• Prostaglandin I2
• Histamine
• Interferon-beta
• Complement factor H

Correct Answer: Histamine

Q16. Which of the following agents specifically inhibits 5-lipoxygenase or leukotriene synthesis and is used in asthma therapy?

• Zileuton
• Indomethacin
• Hydrocortisone
• Aspirin

Correct Answer: Zileuton

Q17. Which mediator acts via GPCRs known as EP receptors in multiple tissues to mediate inflammation and pain?

• Leukotriene C4
• Prostaglandin E2 (PGE2)
• Histamine
• Nitric oxide

Correct Answer: Prostaglandin E2 (PGE2)

Q18. Which cell type is the principal source of tumor necrosis factor-alpha (TNF-α) in acute inflammation?

• Neutrophils
• Macrophages
• Endothelial cells
• Lymphocytes

Correct Answer: Macrophages

Q19. Which mediator is most associated with sustained vasodilation and pain during chronic inflammation and produced by macrophages?

• Leukotriene B4
• Interleukin-10
• Nitric oxide (NO)
• Platelet-activating factor (PAF)

Correct Answer: Nitric oxide (NO)

Q20. Which inhibitor class reduces expression of COX-2 and phospholipase A2 through genomic effects on inflammatory gene transcription?

• Cyclooxygenase-2 selective inhibitors (coxibs)
• Corticosteroids
• Nonselective NSAIDs
• Antihistamines

Correct Answer: Corticosteroids

Q21. Which molecule is an important mediator of leukocyte adhesion and migration, belonging to the integrin family ligand on endothelial cells?

• ICAM-1 (Intercellular adhesion molecule-1)
• Histamine H1 receptor
• C3a
• VEGF

Correct Answer: ICAM-1 (Intercellular adhesion molecule-1)

Q22. Which reactive molecule produced by neutrophils contributes to microbial killing but can also cause host tissue damage?

• Superoxide anion (O2−) and other reactive oxygen species
• Prostaglandin E2
• Interleukin-4
• Thromboxane B2

Correct Answer: Superoxide anion (O2−) and other reactive oxygen species

Q23. Which drug class blocks prostaglandin synthesis by reversible inhibition of COX enzymes and is commonly used for pain and inflammation?

• Corticosteroids
• NSAIDs (nonsteroidal anti-inflammatory drugs)
• Antibiotics
• Monoclonal antibodies against TNF

Correct Answer: NSAIDs (nonsteroidal anti-inflammatory drugs)

Q24. Which leukotriene is most associated with bronchoconstriction and increased vascular permeability in asthma?

• LTB4
• LTC4/LTD4/LTE4 (cysteinyl leukotrienes)
• PGE2
• PGI2

Correct Answer: LTC4/LTD4/LTE4 (cysteinyl leukotrienes)

Q25. Which mediator directly activates endothelial cells to promote expression of adhesion molecules and increase leukocyte recruitment?

• IL-1 and TNF-α
• Histamine only
• Bradykinin only
• Glucocorticoids

Correct Answer: IL-1 and TNF-α

Q26. Which complement activation pathway is initiated by antigen-antibody complexes?

• Lectin pathway
• Alternative pathway
• Classical pathway
• Coagulation pathway

Correct Answer: Classical pathway

Q27. Which lipid mediator inhibits neutrophil chemotaxis and promotes resolution of inflammation?

• Leukotriene B4
• Lipoxin A4
• Thromboxane A2
• Prostaglandin H2

Correct Answer: Lipoxin A4

Q28. Which receptor subtype mediates histamine-induced bronchoconstriction and increased vascular permeability?

• H1 receptor
• H2 receptor
• H3 receptor
• H4 receptor

Correct Answer: H1 receptor

Q29. Which mediator is measured indirectly by an elevated erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) during acute inflammation?

• Histamine
• CRP is itself an acute-phase protein induced by IL-6
• Nitric oxide levels in plasma
• Leukotriene levels

Correct Answer: CRP is itself an acute-phase protein induced by IL-6

Q30. Which enzyme is the target of low-dose aspirin in platelets to reduce thromboxane A2 production?

• COX-2
• COX-1
• 5-Lipoxygenase
• Phospholipase C

Correct Answer: COX-1

Q31. Which mediator class includes interferon-gamma (IFN-γ) that activates macrophages and promotes chronic inflammation?

• Cytokines
• Eicosanoids
• Complement fragments
• Kinins

Correct Answer: Cytokines

Q32. Which drug blocks TNF-α activity and is used to treat rheumatoid arthritis and other inflammatory diseases?

• Infliximab (anti-TNF monoclonal antibody)
• Ibuprofen (NSAID)
• Prednisone (corticosteroid)
• Zileuton (5-LOX inhibitor)

Correct Answer: Infliximab (anti-TNF monoclonal antibody)

Q33. Which mediator is primarily responsible for the edema formation in immediate hypersensitivity by acting on arterioles and venules?

• Interleukin-8
• Histamine
• Transforming growth factor-beta
• Interferon-alpha

Correct Answer: Histamine

Q34. Which eicosanoid is produced by vascular endothelium and inhibits platelet aggregation while causing vasodilation?

• Thromboxane A2
• Prostacyclin (PGI2)
• Leukotriene B4
• Prostaglandin F2α

Correct Answer: Prostacyclin (PGI2)

Q35. Which mediator released by neutrophils amplifies inflammation and recruits additional neutrophils via positive feedback?

• IL-10
• Leukotriene B4 (LTB4)
• Prostaglandin I2
• Annexin A1

Correct Answer: Leukotriene B4 (LTB4)

Q36. Which anti-inflammatory protein is induced by glucocorticoids and inhibits phospholipase A2?

• Cyclooxygenase-2
• Annexin (lipocortin)
• TNF-α
• Complement C3

Correct Answer: Annexin (lipocortin)

Q37. Which mediator is central to the pain and hyperalgesia associated with inflammation by sensitizing nociceptors?

• Prostaglandin E2 (PGE2)
• C3b
• INA-1
• Interleukin-2

Correct Answer: Prostaglandin E2 (PGE2)

Q38. Which pharmacological agent is a leukotriene receptor antagonist used in asthma management?

• Montelukast
• Rofecoxib
• Prednisolone
• Ibuprofen

Correct Answer: Montelukast

Q39. Which mediator family includes molecules that directly opsonize pathogens to enhance phagocytosis?

• Complement components (e.g., C3b)
• Prostaglandins
• Leukotrienes
• Kinins

Correct Answer: Complement components (e.g., C3b)

Q40. Which process describes the firm adhesion of leukocytes to endothelium mediated by integrins and ICAM/VCAM interactions?

• Diapedesis
• Rolling
• Adhesion and arrest (firm adhesion)
• Phagocytosis

Correct Answer: Adhesion and arrest (firm adhesion)

Q41. Which reactive nitrogen species synthesized by inducible nitric oxide synthase (iNOS) contributes to microbial killing in macrophages?

• Nitric oxide (NO)
• Prostaglandin D2
• Leukotriene C4
• Histamine

Correct Answer: Nitric oxide (NO)

Q42. Which mediator promotes fibroblast proliferation and collagen deposition during chronic inflammation and tissue repair?

• Transforming growth factor-beta (TGF-β)
• IL-8
• Leukotriene B4
• Bradykinin

Correct Answer: Transforming growth factor-beta (TGF-β)

Q43. Which anti-inflammatory drug preferentially inhibits COX-2 and was designed to reduce gastric side effects of nonselective NSAIDs?

• Celecoxib
• Aspirin
• Indomethacin
• Naprosyn

Correct Answer: Celecoxib

Q44. Which mediator is a potent inducer of endothelial permeability and pain and is derived from kallikrein-kinin system?

• Histamine
• Bradykinin
• IL-12
• Prostaglandin I2

Correct Answer: Bradykinin

Q45. Which mediator class includes small proteins like IL-8 (CXCL8) that direct leukocyte chemotaxis?

• Chemokines
• Eicosanoids
• Complement proteins
• Antibodies

Correct Answer: Chemokines

Q46. Which laboratory test is most specifically used to detect elevated levels of the acute-phase reactant CRP during inflammation?

• Complete blood count (CBC)
• C-reactive protein (CRP) assay
• Serum amylase
• Urinalysis

Correct Answer: C-reactive protein (CRP) assay

Q47. Which mediator promotes endothelial cell retraction leading to increased vascular permeability by acting on VE-cadherin junctions?

• VEGF (vascular endothelial growth factor)
• Interferon-gamma
• Annexin A1
• Interleukin-2

Correct Answer: VEGF (vascular endothelial growth factor)

Q48. Which enzyme deficiency or inhibition would reduce synthesis of both prostaglandins and thromboxanes?

• Phospholipase A2 deficiency
• COX (cyclooxygenase) inhibition
• 5-Lipoxygenase inhibition
• Thromboxane synthase inhibition only

Correct Answer: COX (cyclooxygenase) inhibition

Q49. Which investigative technique can quantify specific cytokines such as TNF-α or IL-1 in biological samples?

• ELISA (enzyme-linked immunosorbent assay)
• Gram staining
• Magnetic resonance imaging (MRI)
• Urine dipstick

Correct Answer: ELISA (enzyme-linked immunosorbent assay)

Q50. Which mediator produced by regulatory cells dampens inflammation and promotes resolution by inhibiting proinflammatory cytokine production?

• Interleukin-10 (IL-10)
• Interleukin-1 (IL-1)
• TNF-α
• Leukotriene B4

Correct Answer: Interleukin-10 (IL-10)

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