Neuroscience Program, Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine and the Fifth Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China; Advanced Medical Technology Center, the First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.
Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.
Curr Biol. 2024 Apr 8;34(7):1453-1468.e6. doi: 10.1016/j.cub.2024.02.060. Epub 2024 Mar 13.
Itch encompasses both sensory and emotional dimensions, with the two dimensions reciprocally exacerbating each other. However, whether a shared neural circuit mechanism governs both dimensions remains elusive. Here, we report that the anterior insular cortex (AIC) is activated by both histamine-dependent and -independent itch stimuli. The activation of AIC elicits aversive emotion and exacerbates pruritogen-induced itch sensation and aversion. Mechanistically, AIC excitatory neurons project to the GABAergic neurons in the dorsal bed nucleus of the stria terminalis (dBNST). Manipulating the activity of the AIC → dBNST pathway affects both itch sensation and itch-induced aversion. Our study discovers the shared neural circuit (AIC → dBNST pathway) underlying the itch sensation and aversion, highlights the critical role of the AIC as a central hub for the itch processing, and provides a framework to understand the neural mechanisms underlying the sensation and emotion interaction.
痒觉包含感觉和情绪两个维度，这两个维度相互加剧。然而，是否存在一个共同的神经回路机制来控制这两个维度仍然难以捉摸。在这里，我们报告说，前脑岛皮层（AIC）被组氨酸依赖性和非依赖性痒觉刺激所激活。AIC 的激活会引起厌恶情绪，并加剧致痒原引起的痒感和厌恶感。从机制上讲，AIC 兴奋性神经元投射到终纹床核背侧的 GABA 能神经元（dBNST）。操纵 AIC→dBNST 通路的活动会影响痒觉和痒诱发的厌恶感。我们的研究发现了痒觉和厌恶感的共享神经回路（AIC→dBNST 通路），强调了 AIC 作为痒觉处理中枢枢纽的关键作用，并为理解感觉和情绪相互作用的神经机制提供了一个框架。
