中文摘要：

本文旨在检测谷氨酸促代谢型受体（metabotropic glutamate receptors，mGluR）各亚型在肺腺癌A549细胞中的表达，并进一步探讨呈高表达的mGluR8和mGluR4激活对A549细胞体外生长的影响。采用real-timePCR技术检测A549细胞mGluR各亚型的mRNA表达，采用免疫组化技术检测A549细胞以及肺腺癌组织mGluR8和mGluR4蛋白表达。采用CCK-8试剂盒检测细胞生长，EdU掺入检测细胞DNA合成率，hoechst33258染色及流式细胞仪检测细胞的凋亡的变化，分别观察mGluR8的激动剂（S）-3,4-DCPG及mGluR4的激动剂VU0155041对A549细胞生长的影响。结果显示：A549细胞I组促代谢型受体mGluRl和mGluR5mRNA呈低水平表达，II组促代谢型受体mGluR2和mGluR3mRNA无表达，III组促代谢型受体mGluR4、mGluR6、mGluR7和mGluR8mRNA均有表达，其中以mGluR8的mRNA表达水平最高，mGluR4表达次之；A549细胞及部分忠者肺腺癌组织上有mGluR4和mGluR8的蛋白表达。VU0155041对A549细胞的体外生长无明显影响，而（S）-3，4-DCPG呈剂量依赖性抑制A549细胞的生长，并促进其凋亡。这些结果揭示mGluR8激活具有抑制肺癌细胞生长作用，为肺癌防治的研究提供新的线索。

英文摘要：

This study aims to detect the expression of metabotropic glutamate receptors （mGluRs） in lung carcinoma A549 cells, and to investigate the effects of mGluR8 and mGluR4 activation on the growth ofA549 cells in vitro. The mRNA expression levels of the 8 subtypes of mGluRs in A549 cells were determined by real-time PCR. Immunohistochemistry was used to analyze the protein expression of mGluR4 and mGluR8 in A549 cells and lung tissue sections obtained from lung adenocareinoma patients. To observe the effects of mGluR8 and mGluR4 activation on the growth ofA549 cells, the cultured cells were treated with （S）-3,4-DCPG （an agonist of mGluRS） and VU0155041 （an agonist of mGluR4）, respectively, and then the cell viability was analyzed by CCK-8 kit, the percentage of DNA synthesis was detected by EdU incorporation, and the apoptosis of the cells was measured by hoechst 33258 staining and flow cytometry. The results showed that there were low expressions of mGluR1, mGluR5, mGluR6, mGluR7 mRNA, no expression of mGluR2 and mGluR3 mRNA, and high expressions of mGluR8 and mGluR4 mRNA in A549 cells. Accordingly, there were also mGluR4 and mGluR8 protein expressions in the A549 cells and the lung adenocarcinoma tissue sections. VU0155041 hadno effect on the growth ofA549 cells, but （S）-3,4-DCPG significantly decreased the cells＇ growth in a dose-dependent manner and increased the apoptosis of the cells. The results revealed a role of mGluR8 in the growth and apoptosis ofA549 cells and suggested a potential target for clinical treatment of lung cancer.