Which mediator is primarily responsible for vasodilation and fever in acute inflammation?

Which mediator is primarily responsible for vasodilation and fever in acute inflammation?

• A. PGE2
• B. Histamine
• C. LTB4
• D. C5a

Answer: (A)

Prostaglandin E2 is produced during acute inflammation from arachidonic acid via COX enzymes and acts on vascular smooth muscle to promote vasodilation, contributing to redness and heat. It also travels to the hypothalamus, raising the set point and causing fever. While histamine drives rapid vasodilation and increased permeability early on, fever is primarily mediated by PGE2. LT B4 and C5a mainly promote neutrophil chemotaxis and activation rather than fever. So the mediator that best accounts for both vasodilation and fever is prostaglandin E2.

Prostaglandin E2 is produced during acute inflammation from arachidonic acid via COX enzymes and acts on vascular smooth muscle to promote vasodilation, contributing to redness and heat. It also travels to the hypothalamus, raising the set point and causing fever. While histamine drives rapid vasodilation and increased permeability early on, fever is primarily mediated by PGE2. LT B4 and C5a mainly promote neutrophil chemotaxis and activation rather than fever. So the mediator that best accounts for both vasodilation and fever is prostaglandin E2.