Amino acid transport system A is involved in inflammatory nociception in rats

作者：Wang Jing; Geng Bin; Shen Hai Li; Xu Xu; Wang Hong; Wang Cui Fang; Ma Jing Ling; Wang Zhi Ping^*

来源：Brain Research, 2012, 1449: 38-45.

DOI：10.1016/j.brainres.2012.02.018

• Amino acid transport system A
• Methylaminoisobutyric acid
• Glial fibrillary acid protein
• Formalin test
• Spinal cord

Previous studies have indicated that central sensitization is a state of increased excitability of nociceptive neurons in the spinal dorsal horn following peripheral tissue injury and/or inflammation and astrocytes play an important role in the central sensitization. The current study investigated the role of amino acid transport system A in central sensitization and hyperalgesia induced by intraplantar injection of formalin in rats. Formalin (5%, 50 mu l) injected subcutaneously into the unilateral hindpaw pad induced typical biphase nociceptive behaviors, including licking/biting and flinching of the injected paw and an increase of glial fibrillary acid protein (GFAP, an activated astrocyte marker) expression in spinal dorsal horn, and these effects could be attenuated by intrathecal injection of the competitive inhibitor of amino acid system A transporter, methylaminoisobutyric acid (MeAIB, 0.1, 0.3, 0.5, and 0.7 mmol), in a dose-dependent manner. Intrathecal injection of vehicle (PBS) had no effect on the formalin-induced nociceptive behaviors and increase of the GFAP. These findings suggest that amino acid transport system A is involved in inflammation-induced nociception, and inhibition of this transporter system results in inhibition of the central sensitization and hyperalgesia.

• 出版日期2012-4-17
• 单位兰州大学