Leukotriene B4 (LTB4) is primarily derived from arachidonic acid via which enzymatic pathway and exerts what key inflammatory effect?

• A Cyclooxygenase pathway; platelet aggregation
• B Cytochrome P450 pathway; vasoconstriction
• C 5-lipoxygenase pathway; potent neutrophil chemotaxis ✓
• D Lipooxygenase-15 pathway; anti-inflammatory lipoxin synthesis

Explanation

LTB4 is generated from arachidonic acid by 5-lipoxygenase and FLAP (5-lipoxygenase-activating protein), producing a potent chemoattractant and activator of neutrophils and macrophages, promoting degranulation and superoxide generation. Cyclooxygenase produces prostaglandins and thromboxane A2 (the latter causing platelet aggregation). Lipoxins derived from 15-LOX pathway are anti-inflammatory mediators that suppress leukocyte recruitment. The CYP450 pathway produces epoxyeicosatrienoic acids.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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