Functional diversity of somatostatin interneurons in visual cortical circuits

项目总结： GABA能中间神经元是新皮质环路正常发育和功能的中枢。在……里面 特别是，表达生长抑素(SST-INS)的细胞被认为在这两种情况下都起着关键作用 自发的和感觉诱发的神经元活动，主要是通过它们对树突的强烈抑制 兴奋性锥体神经元。然而，不同类别的SST-ins在皮质深部的功能作用 层仍然未知。此外，鉴于SST-ins在成年动物皮质浅层中的作用 已经得到了很好的表征，但它们在颗粒层下的功能尚不清楚。我们的初步数据显示 SST-INS的性质在不同的大脑皮层上有所不同，因此可能发挥不同的作用。为了进一步 为了探索这一观察结果，我们建议结合一些方法，包括光遗传学 操控，双光子和病毒追踪。我们将检验以下假设：(1)SST-IN种群在 视皮层的浅层和深层有不同的反应，并受到行为的不同调节 由于突触前输入的不同而导致的状态。(2)SST-IN种群在各层的功能上是不同的 它们对感觉加工的影响也不同。我们的结果将提供前所未有的洞察力 SST-ins在新皮质的功能及其与视觉加工的关系。

Project Summary: GABAergic interneurons are central to the normal development and function of neocortical circuits. In particular, cells that express the peptide somatostatin (SST-INs) are thought to play critical roles in both spontaneous and sensory-evoked neuronal activity, primarily via their robust inhibition of the dendrites of excitatory pyramidal neurons. However, the functional roles of the diverse classes of SST-INs in deep cortical layers remain unknown. Furthermore, whereas the role of SST-INs in superficial cortical layers of adult animals has been well characterized, their function in the infragranular layers is unknown. Our preliminary data suggest the properties of SST-Ins vary across different cortical layers and thus may serve different roles. To further explore this observation, we propose to combine a number of methodological approaches, including optogenetic manipulations, 2-photon and viral tracing. We will test the following hypotheses: (1) SST-IN populations in superficial and deep layers of visual cortex have distinct responses and differentially regulated by behavioral state due to differences in presynaptic inputs. (2) SST-IN populations are functionally distinct across the layers and differ in their impact on sensory processing. Our results will provide an unprecedented level of insight into the function of SST-INs and their relationship to visual processing in the neocortex.