Zhang J Y, Ashby C R, Wang R Y
Department of Psychiatry and Behavioral Sciences, State University of New York, Stony Brook.
J Neural Transm Gen Sect. 1994;95(3):165-72. doi: 10.1007/BF01271563.
In this study, we examined the response of spontaneously active as well as quiescent cells (L-glutamate-activated) in the rat medial prefrontal cortex (mPFc) to the iontophoresis of 2-methylserotonin (2-Me-5-HT, 5-HT3 receptor agonist), (+/-)-2,5-dimethoxy-(4-iodo-phenyl)-2-aminopropane (DOI, 5-HT2A,2C receptor agonist), 8-hydroxy-N,N-di-propylamino tetralin (8-OH-DPAT, 5-HT1A receptor agonist) and gamma-aminobutyric acid (GABA, a non-selective GABA receptor agonist) after the intracerebral administration of pertussis toxin, an inactivator of the Gi/o protein. This was accomplished using the techniques of extracellular single cell recording and iontophoresis. The administration of pertussis toxin (0.5 microgram, 24 hours before the experiment) into the mPFc did not alter the response of mPFc cells to the iontophoresis of DOI, 2-Me-5HT or GABA compared to saline treated controls. However, the response of mPFc cells to the iontophoresis of 8-OH-DPAT was significantly attenuated in the animals pretreated with pertussis toxin compared to controls. These results suggest that the 5-HT1A but not 5-HT2A,2C or 5-HT3 receptor is coupled to the Gi/o protein.
在本研究中，我们检测了大鼠内侧前额叶皮质（mPFc）中自发活跃以及静止细胞（L-谷氨酸激活的）对2-甲基血清素（2-Me-5-HT，5-HT3受体激动剂）、（±）-2,5-二甲氧基-（4-碘苯基）-2-氨基丙烷（DOI，5-HT2A、2C受体激动剂）、8-羟基-N,N-二丙基氨基四氢萘（8-OH-DPAT，5-HT1A受体激动剂）和γ-氨基丁酸（GABA，一种非选择性GABA受体激动剂）离子导入的反应，这些反应是在脑内注射百日咳毒素（一种Gi/o蛋白灭活剂）之后进行检测的。这是通过细胞外单细胞记录和离子导入技术来完成的。与用生理盐水处理的对照组相比，向mPFc注射百日咳毒素（0.5微克，实验前24小时）并未改变mPFc细胞对DOI、2-Me-5HT或GABA离子导入的反应。然而，与对照组相比，用百日咳毒素预处理的动物中mPFc细胞对8-OH-DPAT离子导入的反应显著减弱。这些结果表明5-HT1A受体而非5-HT2A、2C或5-HT3受体与Gi/o蛋白偶联。
