Excitatory and inhibitory synapses in neuropeptide Y-expressing striatal interneurons.
Excitatory and inhibitory synapses in neuropeptide Y-expressing striatal interneurons.
复制标题
表达神经肽 Y 的纹状体中间神经元中的兴奋性和抑制性突触。
DOI：
10.1152/jn.00272.2009
复制
发表时间：
2009
影响因子：
2.5
通讯作者：
Vicini,Stefano
中科院分区：
文献类型：
--
作者：
Partridge,JohnG;Janssen,MeganJ;Chou,DavidYT;Abe,Ken;Zukowska,Zofia;Vicini,Stefano
虽然很少见，但中间神经元通过广泛的轴突分支与中等棘神经元突触，在控制纹状体输出方面起着关键作用。利用神经肽Y(NPY)启动子控制绿色荧光蛋白(GFP)表达的转基因小鼠，我们鉴定了NPY中间神经元，并将其与纹状体主神经元进行了比较。我们发现细菌人工染色体(BAC)-npymouse在纹状体表达GFP时，对内源性NPY的表达有很高的保真度。来自NPY神经元的膜片钳分析显示纹状体中间神经元的数量是不同的。在大多数细胞中，我们在细胞外记录中观察到动作电位的自发放电。在膜破裂时，大多数NPY中间神经元可归类为低阈值尖峰中间神经元，具有高输入阻力。电压钳记录显示，GABA和谷氨酸门控离子通道均介导突触传入这些纹状体中间神经元。AMPA受体介导的自发兴奋性突触后电流(SEPSCs)在NPY神经元中波幅较小，频率较低。诱发的EPSCs没有表现出短期的可塑性，但有一定的整流性。去势的N-甲基-D-天冬氨酸(NMDA)EPSCs具有较快的衰变动力学，对含有NMDA受体阻断剂的NR2B亚基不敏感。自发抑制性突触后电流(SIPSCs)是由GABA受体介导的，所有纹状体神经元的自发抑制性突触后电流(SIPSCs)非常相似。相反，在NPY神经元中，诱发的IPSCs比在其他纹状体神经元中衰退得更快。这些数据首次报道了突触传递到NPY纹状体间神经元的特殊特性。
Although rare, interneurons are pivotal in governing striatal output by extensive axonal arborizations synapsing on medium spiny neurons. Using a genetically modified mouse strain in which a green fluorescent protein (GFP) is driven to be expressed under control of the neuropeptide Y (NPY) promoter, we identified NPY interneurons and compared them with striatal principal neurons. We found that the bacteria artificial chromosome (BAC)-npymouse expresses GFP with high fidelity in the striatum to the endogenous expression of NPY. Patch-clamp analysis from NPY neurons showed a heterogeneous population of striatal interneurons. In the majority of cells, we observed spontaneous firing of action potentials in extracellular recordings. On membrane rupture, most NPY interneurons could be classified as low-threshold spiking interneurons and had high-input resistance. Voltage-clamp recordings showed that both GABA and glutamate gated ion channels mediate synaptic inputs onto these striatal interneurons. AMPA receptor–mediated spontaneous excitatory postsynaptic currents (sEPSCs) were small in amplitude and infrequent in NPY neurons. Evoked EPSCs did not show short-term plasticity but some rectification. EvokedN-methyl-d-aspartate (NMDA) EPSCs had fast decay kinetics and were poorly sensitive to an NR2B subunit containing NMDA receptor blocker. Spontaneous inhibitory postsynaptic currents (sIPSCs) were mediated by GABAAreceptors and were quite similar among all striatal neurons studied. On the contrary, evoked IPSCs decayed faster in NPY neurons than in other striatal neurons. These data report for the first time specific properties of synaptic transmission to NPY striatal interneurons.