Amygdala stimulation evokes time-varying synaptic responses in the gustatory cortex of anesthetized rats.
Amygdala stimulation evokes time-varying synaptic responses in the gustatory cortex of anesthetized rats.
复制标题
DOI：
10.3389/fnint.2011.00003
复制
发表时间：
2011
影响因子：
3.5
通讯作者：
Fontanini A
中科院分区：
文献类型：
--
作者：
Stone ME;Maffei A;Fontanini A
味觉刺激的特征在于特定的享乐价值;它们要么是可口的，要么是厌恶的。快乐值，沿着其他心理层面的口味，编码在味觉皮层（GC）神经反应的时间过程中，并出现通过自上而下的调制由基底外侧杏仁核（BLA）。虽然BLA在调节味觉皮层功能中的重要性已经得到很好的证实，但其输入GC神经元的性质在很大程度上是未知的。有些矛盾的结果，从细胞外记录点兴奋或抑制作用。在这里，我们直接测试的假设，BLA可以引起时变兴奋性和抑制性突触反应，在GC在体内细胞内记录技术在乌拉坦麻醉大鼠。电刺激BLA引起的突触后电位（PSP）的GC神经元，导致从短和长潜伏期组件的组合：一个初始的单突触，突触能电位，随后由多突触，GABA能超极化。如杏仁核诱发电位的动态性质所预测的，以模拟生理放电率（5-40 Hz）的速率的五种BLA刺激的序列在GC细胞中诱发兴奋和抑制的组合。不同成分的大小取决于刺激的频率，兴奋性和抑制性输入的总和在较高频率下达到最大值。这些实验提供了第一个描述的BLA突触输入GC和揭示，杏仁传入可以调节味觉皮层网络的活动和它的处理通过随时间变化的突触动力学的感觉信息。
Gustatory stimuli are characterized by a specific hedonic value; they are either palatable or aversive. Hedonic value, along with other psychological dimensions of tastes, is coded in the time-course of gustatory cortex (GC) neural responses and appears to emerge via top-down modulation by the basolateral amygdala (BLA). While the importance of BLA in modulating gustatory cortical function has been well established, the nature of its input onto GC neurons is largely unknown. Somewhat conflicting results from extracellular recordings point to either excitatory or inhibitory effects. Here, we directly test the hypothesis that BLA can evoke time-varying – excitatory and inhibitory – synaptic responses in GC using in vivo intracellular recording techniques in urethane anesthetized rats. Electrical stimulation of BLA evoked a post-synaptic potential (PSP) in GC neurons that resulted from a combination of short and long latency components: an initial monosynaptic, glutamatergic potential followed by a multisynaptic, GABAergic hyperpolarization. As predicted by the dynamic nature of amygdala evoked potentials, trains of five BLA stimuli at rates that mimic physiological firing rates (5–40 Hz) evoke a combination of excitation and inhibition in GC cells. The magnitude of the different components varies depending on the frequency of stimulation, with summation of excitatory and inhibitory inputs reaching its maximum at higher frequencies. These experiments provide the first description of BLA synaptic inputs to GC and reveal that amygdalar afferents can modulate gustatory cortical network activity and its processing of sensory information via time-varying synaptic dynamics.