The fever that follows release of IL-1 and TNF during systemic inflammation is produced through which final common pathway?
- A Direct activation of thermosensitive neurons by circulating cytokines crossing the blood-brain barrier
- B Bradykinin-mediated vasodilation of cutaneous vessels reducing heat dissipation
- C Cytokine-induced prostaglandin E2 synthesis in the hypothalamic vascular organ of the lamina terminalis ✓
- D IL-6 driven hepatic production of C-reactive protein acting on the hypothalamus
Correct answer: C. Cytokine-induced prostaglandin E2 synthesis in the hypothalamic vascular organ of the lamina terminalis
Explanation
IL-1, TNF and IL-6 act on endothelial cells of the organum vasculosum of the lamina terminalis, inducing cyclooxygenase-dependent prostaglandin E2 synthesis locally. PGE2 then resets the hypothalamic set point upward, causing shivering and vasoconstriction. This is why NSAIDs and acetaminophen are antipyretic. CRP is a marker of the acute phase response and does not act on the hypothalamus.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.