5-羟色胺（5-HT）及其受体的共同激活诱导了大鼠视觉皮层中谷氨酸能突触传递的减弱。

Co-activation of both 5-HT and 5-HT receptors induced attenuation of glutamatergic synaptic transmission in the rat visual cortex.

作者信息

Li Yan-Hai, Xiang Kangjian, Xu Xingzhe, Zhao Xuefei, Li Youjun, Zheng Liang, Wang Jue

机构信息

The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Research Center of Rehabilitation Science and Technology, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, PR China; National Engineering Research Center of Health Care and Medical Devices, PR China.

出版信息

Neurosci Lett. 2018 Nov 1;686:122-126. doi: 10.1016/j.neulet.2018.09.013. Epub 2018 Sep 8.

DOI:10.1016/j.neulet.2018.09.013

PMID:30205142

Abstract

It has been suggested that functional interactions between the 5-HT receptor subtypes may modulate glutamatergic synaptic transmission. In this study, we used whole-cell patch-clamp recordings to test the role of 5-HT receptors in mediating the AMPA receptor-mediated miniature excitatory postsynaptic currents (mEPSCs) in layer II/III pyramidal neurons of the rat visual cortex. We found that the AMPA receptor-mediated component of mEPSCs could be inhibited by exogenously applied 5-HT. 5-HT significantly reduced the glutamatergic mEPSC amplitude and increased the inter-event interval of glutamatergic mEPSCs. Bath application of 5-CT or 8-OH-DPAT (the 5-HT and 5-HT receptor agonist) mimicked 5-HT in its effect on mEPSCs. Additionally, a selective antagonist for the 5-HT receptor, SB-269970, displayed no influence on the inhibition of glutamatergic synaptic transmission by 5-CT or 8-OH-DPAT. Similar results were obtained by exogenously applied WAY-100135, the selective 5-HT receptor antagonist. However, the inhibition of glutamatergic synaptic transmission by 5-CT or 8-OH-DPAT was completely blocked by co-application of WAY-100135 and SB-269970. Altogether, our results indicated that 5-HT suppressed glutamatergic synaptic transmission by co-activation of synaptic 5-HT receptors and 5-HT receptors in layer II/III pyramidal neurons of the rat visual cortex.

摘要

有人提出，5-羟色胺（5-HT）受体亚型之间的功能相互作用可能调节谷氨酸能突触传递。在本研究中，我们使用全细胞膜片钳记录来测试5-HT受体在介导大鼠视觉皮层II/III层锥体神经元中α-氨基-3-羟基-5-甲基-4-异恶唑丙酸（AMPA）受体介导的微小兴奋性突触后电流（mEPSCs）中的作用。我们发现，外源性应用5-HT可抑制mEPSCs的AMPA受体介导成分。5-HT显著降低了谷氨酸能mEPSC的幅度，并增加了谷氨酸能mEPSCs的事件间隔。浴用5-羧色胺（5-CT）或8-羟基-二丙基氨基四氢萘（8-OH-DPAT，5-HT和5-HT受体激动剂）对mEPSCs的作用与5-HT相似。此外，5-HT受体的选择性拮抗剂SB-269970对5-CT或8-OH-DPAT抑制谷氨酸能突触传递没有影响。外源性应用选择性5-HT受体拮抗剂WAY-100135也得到了类似的结果。然而，5-CT或8-OH-DPAT对谷氨酸能突触传递的抑制作用在同时应用WAY-100135和SB-269970时被完全阻断。总之，我们的结果表明，5-HT通过共同激活大鼠视觉皮层II/III层锥体神经元中的突触5-HT受体和5-HT受体来抑制谷氨酸能突触传递。