Wercberger Racheli, Basbaum Allan I
Department of Anatomy and Neuroscience Graduate Program, University California San Francisco, San Francisco, CA 94158.
Curr Opin Physiol. 2019 Oct;11:109-115. doi: 10.1016/j.cophys.2019.10.002. Epub 2019 Oct 10.
Today there are extensive maps of the molecular heterogeneity of primary afferents and dorsal horn interneurons, yet there is a dearth of molecular and functional information regarding the projection neurons that transmit pain and itch information to the brain. Additionally, most contemporary research into the spinal cord and medullary projection neurons focuses on neurons in the superficial dorsal horn; the contribution of deep dorsal horn and even ventral horn projection neurons to pain and itch processing is often overlooked. In the present review we integrate conclusions from classical as well as contemporary studies and provide a more balanced view of the diversity of projection neurons. A major question addressed is the extent to which labeled-lines are maintained in these different populations or whether the brain generates distinct pain and itch percepts by decoding complex convergent inputs that engage projection neurons.
如今，已有关于初级传入神经元和背角中间神经元分子异质性的详尽图谱，但对于将疼痛和瘙痒信息传递至大脑的投射神经元，分子和功能信息却十分匮乏。此外，大多数针对脊髓和延髓投射神经元的当代研究聚焦于浅背角中的神经元；深背角乃至腹角投射神经元对疼痛和瘙痒处理的贡献往往被忽视。在本综述中，我们整合了经典研究和当代研究的结论，对投射神经元的多样性给出了更为平衡的观点。所探讨的一个主要问题是，在这些不同的神经元群体中，标记线在多大程度上得以保留，或者大脑是否通过解码与投射神经元相关的复杂汇聚输入来产生不同的疼痛和瘙痒感知。
