Department of Biology, Stanford University, Stanford, CA 94305, USA.
Department of Biology, Stanford University, Stanford, CA 94305, USA.
Exp Neurol. 2019 Aug;318:42-49. doi: 10.1016/j.expneurol.2019.04.009. Epub 2019 Apr 20.
The spinal cord dorsal horn is the first relay station of the neural network for processing somatosensory information. High-throughput optical recording methods facilitate the study of sensory coding in the cortex but have not been successfully applied to study spinal cord circuitry until recently. Here, we review the development of an in vivo two-photon spinal calcium imaging preparation and biological findings from the first systematic characterization of the spinal response to cutaneous thermal stimuli, focusing on the difference between the coding of heat and cold, and the contribution of different peripheral inputs to thermosensory response in the spinal cord. Here we also report that knockout of TRPV1 channel impairs sensation of warmth, and somatostatin- and calbindin2-expressing neurons in the spinal dorsal horn preferentially respond to heat. Future work combining this technology with genetic tools and animal models of chronic pain will further elucidate the role of each neuronal type in the spinal thermosensory coding and their plasticity under pathological condition.
脊髓背角是处理躯体感觉信息的神经网络的第一中继站。高通量光学记录方法促进了对大脑皮层感觉编码的研究，但直到最近才成功应用于研究脊髓回路。在这里，我们回顾了体内双光子脊髓钙成像制备的发展，以及首次对皮肤热刺激的脊髓反应进行系统特征描述的生物学发现，重点关注热和冷编码之间的差异，以及不同外周输入对脊髓热敏反应的贡献。在这里，我们还报告 TRPV1 通道的敲除会损害温暖感觉，而脊髓背角中表达生长抑素和钙结合蛋白 2 的神经元优先对热做出反应。未来将这项技术与遗传工具和慢性疼痛动物模型相结合的工作，将进一步阐明每种神经元类型在脊髓热敏编码中的作用及其在病理条件下的可塑性。
