Assessing Inflammatory Pain in Animal Studies: An Overview of the Formalin Test

Document Type : Systematic Review

Authors
F. Jalali
K. Alami
H. Azizi
Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Abstract
Pain, a complex and debilitating experience, significantly impacts the quality of life. It is considered as a primary reason for seeking medical care. Inflammatory pain, resulting from tissue injury, is characterized by the release of inflammatory mediators that activate nociceptive pathways, leading to heightened sensitivity. Assessment of inflammatory pain is necessary for understanding its mechanism and developing effective treatment strategies. This study provides an overview of the formalin test, a widely used animal model for assessing inflammatory pain. The test comprises distinct phases (phase I, interphase, and phase II), which reflect acute and tonic pain responses. As a tool for evaluating analgesic efficacy and pain mechanisms, the formalin test has been instrumental in advancing our understanding of pain biology and the development of novel therapeutic approaches.

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Subjects

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Pathobiology Reserach
Volume 27, Issue 4
December 2024
Pages 7-14