Writhing test is a chemical method used to induce pain of peripheral origin by injection of irritant principles like phenylquinone, acetic acid in mice. Analgesic activity of the test compound is inferred from decrease in the frequency of writhings.

Why is acetic acid used in writhing test?

Analgesic activity of the test compound is inferred from a decrease in the frequency of writhings. Acetic acid induces an inflammatory response in the abdominal cavity, with subsequent activation of nociceptors (Collier et al., 1968).

How does acetic acid induce pain?

Acetic acid is commonly usedin the writhing test to induce pain sensation due to its mechanism of action that leads to production of a localized inflammatory response from the release of free AA from tissue phospholipids via COX-producing prostaglandin [133]. ...