Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA.
Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Sci Rep. 2021 Mar 3;11(1):5084. doi: 10.1038/s41598-021-84516-y.
Laser microsurgery has long been an important means of assessing the functions of specific cells and tissues. Most laser ablation systems use short, highly focused laser pulses to create plasma-mediated lesions with dimensions on the order of the wavelength of light. While the small size of the lesion enables ablation with high spatial resolution, it also makes it difficult to ablate larger structures. We developed an infrared laser ablation system capable of thermally lesioning tissues with spot sizes tunable by the duration and amplitude of laser pulses. We used our laser system in the roundworm C. elegans to kill single neurons and to sever the dorsal and ventral nerve cords, structures that are difficult to lesion using a plasma-based ablation system. We used these ablations to investigate the source of convulsions in a gain-of-function mutant for the acetylcholine receptor ACR-2. Severing the ventral nerve cord caused convulsions to occur independently anterior and posterior to the lesion, suggesting that convulsions can arise independently from distinct subsets of the motor circuit.
激光微手术一直是评估特定细胞和组织功能的重要手段。大多数激光烧蚀系统使用短而高度聚焦的激光脉冲，以等离子体为媒介产生尺寸与光的波长相当的损伤。虽然损伤的小尺寸能够实现高空间分辨率的烧蚀，但也使得难以烧蚀更大的结构。我们开发了一种红外激光烧蚀系统，能够通过激光脉冲的持续时间和幅度来调节光斑尺寸，从而对组织进行热损伤。我们在秀丽隐杆线虫中使用我们的激光系统杀死单个神经元，并切断背侧和腹侧神经索，这些结构使用基于等离子体的烧蚀系统很难损伤。我们使用这些烧蚀来研究乙酰胆碱受体 ACR-2 功能获得突变体中抽搐的来源。切断腹侧神经索会导致损伤前后独立发生抽搐，这表明抽搐可以独立于运动回路的不同子集发生。
