Korol Sergiy V, Tafreshiha Atieh, Bhandage Amol K, Birnir Bryndis, Jin Zhe
Department of Neuroscience, Division of Physiology, Uppsala University, Uppsala, Sweden.
Department of Neuroscience, Division of Physiology, Uppsala University, Uppsala, Sweden.
Neurosci Lett. 2018 Apr 3;671:76-81. doi: 10.1016/j.neulet.2018.02.022. Epub 2018 Feb 12.
Insulin, a pancreatic hormone, can access the central nervous system, activate insulin receptors distributed in selective brain regions and affect various cellular functions such as neurotransmission. We have previously shown that physiologically relevant concentration of insulin potentiates the GABA receptor-mediated tonic inhibition and reduces excitability of rat hippocampal CA1 neurons. The central nucleus of the amygdala (CeA) comprises heterogeneous neuronal populations that can respond to hormonal stimulus. Using quantitative PCR and immunofluorescent labeling, we report that the mRNA and protein of the insulin receptor are abundantly expressed in the rat CeA. The insulin receptor mRNA is also detected in the CeA from post-mortem human brain samples. Furthermore, our whole-cell patch-clamp recordings show that the application of insulin (5 and 50 nM) selectively enhances the frequency and amplitude of spontaneous inhibitory postsynaptic currents (sIPSCs) in rat CeA neurons. Our findings reveal that GABAergic synaptic transmission is a target in the CeA for insulin receptor signaling that may underlie insulin modulation of emotion- and feeding-related behaviors.
胰岛素作为一种胰腺激素，能够进入中枢神经系统，激活分布于特定脑区的胰岛素受体，并影响诸如神经传递等多种细胞功能。我们之前已经表明，生理相关浓度的胰岛素可增强GABA受体介导的紧张性抑制，并降低大鼠海马CA1神经元的兴奋性。杏仁核中央核（CeA）由能够对激素刺激产生反应的异质性神经元群体组成。通过定量PCR和免疫荧光标记，我们报告胰岛素受体的mRNA和蛋白在大鼠CeA中大量表达。在死后的人脑样本的CeA中也检测到了胰岛素受体mRNA。此外，我们的全细胞膜片钳记录显示，应用胰岛素（5和50 nM）可选择性增强大鼠CeA神经元中自发性抑制性突触后电流（sIPSCs）的频率和幅度。我们的研究结果揭示，GABA能突触传递是CeA中胰岛素受体信号传导的一个靶点，这可能是胰岛素调节情绪和进食相关行为的基础。
