Hypoalgesia in mice lacking GABA transporter subtype 1

• Published in: Journal of neuroscience research 2008-02, Vol.86 (2), p.465-470
• Main Authors: Xu, Yin Fang, Cai, You Qing, Cai, Guo Qiang, Jiang, Jie, Sheng, Zhe Jing, Wang, Zhu Gang, Fei, Jian
• Format: Article
• Language: English
• Subjects: abdominal constriction test; Animals; formalin test; GABA Antagonists - pharmacology; GABA Plasma Membrane Transport Proteins - drug effects; GABA Plasma Membrane Transport Proteins - genetics; GABA Plasma Membrane Transport Proteins - metabolism; GABA transporter; hot-plate test; Mice; Mice, Knockout; Nipecotic Acids - pharmacology; Oximes - pharmacology; Pain - physiopathology; Pain Threshold - drug effects; Pain Threshold - physiology; tail-immersion test
• ISSN: 0360-4012; 1097-4547
• DOI: 10.1002/jnr.21499

γ‐Aminobutyric acid (GABA) transporters play a key role in the regulation of GABA neurotransmission. We reported previously that overexpression of the GABA transporter subtype 1 (GAT1), the major form of the GABA transporter in the CNS, led to hyperalgesia in mice. In the present study, nociceptive responses of GAT1‐knockout mice (GAT1−/−) were compared with those of heterozygous (GAT+/−) and wild‐type (GAT+/+) mice by four conventional pain models (tail‐immersion test, hot‐plate test, acetic acid–induced abdominal constriction test, and formalin test). In addition, the analgesic effects of two GAT1‐selective inhibitors, NO‐711 and tiagabine, were examined in all three genotypes using the same four models. Our data demonstrated that GAT1 deficiency because of genetic knockout or acute blockade by selective inhibitors leads to hypoalgesia in mice. These results confirmed the crucial role of GAT1 in the regulation of nociceptive threshold and suggested that GAT1 inhibitors have the potential for clinical use in pain therapy. © 2007 Wiley‐Liss, Inc.