Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.
Institute of Brain Research, Qingdao International Academician Park, Qingdao, Shandong 266199, China.
Mol Pain. 2022 Jan-Dec;18:17448069221087034. doi: 10.1177/17448069221087034.
The anterior cingulate cortex (ACC) is located in the frontal part of the cingulate cortex, and plays important roles in pain perception and emotion. The thalamocortical pathway is the major sensory input to the ACC. Previous studies have show that several different thalamic nuclei receive projection fibers from spinothalamic tract, that in turn send efferents to the ACC by using neural tracers and optical imaging methods. Most of these studies were performed in monkeys, cats, and rats, few studies were reported systematically in adult mice. Adult mice, especially genetically modified mice, have provided molecular and synaptic mechanisms for cortical plasticity and modulation in the ACC. In the present study, we utilized rabies virus-based retrograde tracing system to map thalamic-anterior cingulate monosynaptic inputs in adult mice. We also combined with a new high-throughput VISoR imaging technique to generate a three-dimensional whole-brain reconstruction, especially the thalamus. We found that cortical neurons in the ACC received direct projections from different sub-nuclei in the thalamus, including the anterior, ventral, medial, lateral, midline, and intralaminar thalamic nuclei. These findings provide key anatomic evidences for the connection between the thalamus and ACC.
前扣带皮层（ACC）位于扣带皮层的前部，在疼痛感知和情绪中发挥重要作用。丘脑皮质通路是 ACC 的主要感觉输入。先前的研究表明，几个不同的丘脑核接收来自脊髓丘脑束的投射纤维，这些纤维通过使用神经示踪剂和光学成像方法反过来向 ACC 发送传出纤维。这些研究大多在猴子、猫和老鼠中进行，很少有系统地在成年老鼠中报道。成年老鼠，特别是基因修饰老鼠，为 ACC 中的皮质可塑性和调制提供了分子和突触机制。在本研究中，我们利用基于狂犬病病毒的逆行追踪系统来描绘成年小鼠中丘脑-前扣带单突触输入。我们还结合了一种新的高通量 VISoR 成像技术来生成三维全脑重建，特别是丘脑。我们发现，ACC 中的皮质神经元接收来自丘脑不同亚核的直接投射，包括前核、腹侧核、内侧核、外侧核、中线核和板内核。这些发现为丘脑和 ACC 之间的连接提供了关键的解剖学证据。
