Question

Which of the following is endogenous pyrogen

• A. PG E2
• B. PG D2
• C. GF2 alpha
• D. PG I2

Answer 1

The Correct Option is A

In the context of physiology and pathology, an endogenous pyrogen is a substance that can cause fever by acting on the hypothalamus to elevate the body's temperature set-point. Among the given options, the correct endogenous pyrogen is:

• PG E2

Explanation: Prostaglandin E2 (PG E2) is recognized as an endogenous pyrogen because it plays a pivotal role in the fever response. When the body detects an infection or inflammation, immune cells release substances that stimulate the production of PG E2. This prostaglandin then acts on the hypothalamus, triggering the thermoregulatory changes that lead to an increase in body temperature, thus causing fever.

Other prostaglandins listed, such as PG D2, GF2 alpha, and PG I2, do not function as pyrogens. They have different roles and effects within the body related to inflammation, vascular functions, and smooth muscle activity, but PG E2 is specifically associated with the fever response mechanism.