Institute of Scientific Research and High Technology Services (INDICASAT-AIP), Center for Neurosciences, Panama.
J Pain Res. 2011;4:301-8. doi: 10.2147/JPR.S24703. Epub 2011 Sep 26.
Studies have shown that N-methyl-D-aspartate (NMDA) receptors play a critical role in pain processing at different levels of the central nervous system.
In this study, we used adult Wistar rats to examine gender differences in the effects of NR2B NMDA antagonism at the level of the anterior cingulate cortex in phasic pain, and in the first and second phases of a formalin test. Rats underwent stereotactic surgery for cannula implantation in the anterior cingulate cortex. After recovery, paw withdrawal latency to a noxious thermal stimulus was assessed. Rats were also subjected to a formalin pain test whereby 60 μL of 5% formalin was injected into the right hind paw.
Female and male rats that received Ro 25-6981, an NR2B antagonist, before formalin injection showed significantly reduced pain responses to the formalin test compared with saline-injected control rats (P < 0.05). No gender differences in phasic pain responses were found in rats treated with Ro 25-6981.
These results suggest that cortical antagonism of the NR2B subunit reduces inflammatory pain levels in both genders of rat.
研究表明 N-甲基-D-天冬氨酸（NMDA）受体在中枢神经系统的不同水平的疼痛处理中起着关键作用。
在这项研究中，我们使用成年 Wistar 大鼠，在前扣带皮层水平上，检查 NR2B NMDA 拮抗作用对相位性疼痛以及福尔马林试验的第一和第二阶段的性别差异。大鼠接受立体定向手术，在前扣带皮层植入套管。恢复后，评估对有害热刺激的足底退缩潜伏期。大鼠还接受福尔马林疼痛测试，其中 60μL 5%福尔马林注入右后爪。
与接受生理盐水注射的对照组大鼠相比，在注射福尔马林之前接受 NR2B 拮抗剂 Ro 25-6981 的雌性和雄性大鼠对福尔马林试验的疼痛反应明显降低（P<0.05）。在接受 Ro 25-6981 治疗的大鼠中，相位性疼痛反应没有性别差异。
这些结果表明，皮质 NR2B 亚基的拮抗作用降低了雄性和雌性大鼠的炎症性疼痛水平。
