Nair V D, Savelli J E, Mishra R K
Department of Psychiatry, McMaster University, Hamilton, Ontario, Canada.
J Mol Neurosci. 1998 Oct;11(2):121-6. doi: 10.1385/JMN:11:2:121.
The expression of dopamine D2 receptor mRNA was studied in rat brain following micro-injection of a competitive N-methyl D-aspartate (NMDA) receptor antagonist at the prefrontal cortex. Male Sprague-Dawley rats cannulated bilaterally into the medial prefrontal cortex were injected with a competitive NMDA receptor antagonist (+/-)-3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP). The levels of mRNA for NMDA-R1 and dopamine D2 receptors were measured by reverse transcriptase-polymerase chain reaction (RT-PCR), and D2 receptor density was quantified by [3H]spiperone binding in the cortex and striatum of these animals. In the prefrontal cortex, the levels of NMDA-R1 receptor mRNA showed significant decrease in CPP-treated animals compared to control animals. However, NMDA-R1 mRNA levels in striatum remained unchanged in any of the experimental groups. The D2 receptor mRNA levels and [3H]spiroperidol binding in prefrontal cortical membranes showed no significant difference between the CPP-treated and control groups of animals. In the striatum, a significant increase in striatal dopamine D2 receptor mRNA levels was shown in animals treated with CPP. The increase in D2 mRNA level was correlated with an increase in the D2 receptor binding sites in the striatal membranes. These results suggest a possible interaction between prefrontal cortical NMDA receptors and striatal dopamine receptors.
在大鼠前额叶皮层微量注射竞争性N-甲基-D-天冬氨酸（NMDA）受体拮抗剂后，研究了多巴胺D2受体mRNA的表达。将双侧插管至内侧前额叶皮层的雄性Sprague-Dawley大鼠注射竞争性NMDA受体拮抗剂（±）-3-（2-羧基哌嗪-4-基）-丙基-1-膦酸（CPP）。通过逆转录聚合酶链反应（RT-PCR）测量NMDA-R1和多巴胺D2受体的mRNA水平，并通过[3H]螺哌隆结合对这些动物皮层和纹状体中的D2受体密度进行定量。在前额叶皮层中，与对照动物相比，CPP处理的动物中NMDA-R1受体mRNA水平显著降低。然而，在任何实验组中，纹状体中的NMDA-R1 mRNA水平均保持不变。CPP处理组和对照组动物的前额叶皮层膜中D2受体mRNA水平和[3H]螺哌啶醇结合无显著差异。在纹状体中，CPP处理的动物纹状体多巴胺D2受体mRNA水平显著增加。D2 mRNA水平的增加与纹状体膜中D2受体结合位点的增加相关。这些结果表明前额叶皮层NMDA受体与纹状体多巴胺受体之间可能存在相互作用。
