Antinociceptive effects of vitamin E in formalin-induced nociceptive response in rats

Hong, Boo Hwi; Ko, Young Kwon; Lee, Young Jae; Han, Kyucheol; Kim, Yoonhee; Lee, Wonhyung

Experimental Research

Neuroanesthesia

Anesthesia and Pain Medicine 2011;6(1):59-62.
Published online January 31, 2011.

Antinociceptive effects of vitamin E in formalin-induced nociceptive response in rats

Boo Hwi Hong, Young Kwon Ko, Young Jae Lee, Kyucheol Han, Yoonhee Kim, Wonhyung Lee

Department of Anesthesiology and Pain Medicine, Chungnam National University College of Medicine, Daejeon, Korea. ane84@cnu.ac.kr

Abstract

BACKGROUND
Reactive oxygen species (ROS) are critically involved in generating pain in various painful conditions, including neuropathic and inflammatory pain. This experiment was conducted in order to assess the antinociceptive effects of vitamin E in the modulation of pain in rats subjected to the formalin test.
METHODS
Five percent formalin was injected into the hind paw after intraperitoneal injection of either vitamin E 1 g/kg dissolved in olive oil or olive oil alone. The Number of flinches were measured in a 5 minute interval for 1 hour.
RESULTS
Formalin injected into the left hind paw induced a biphasic nociceptive behavior. Intraperitoneal injection of vitamin E diminished the nociceptive behavior during phase 1 and 2.
CONCLUSIONS
Systemic administration of vitamin E produces analgesia in a rat model of formalin-induced hyperalgesia. Furthermore, vitamin E affects pain of peripheral origin.

Key Words: Antinociception, Reactive oxygen speices, ROS Scavenger, Vitamin E