Krieger Jakob, Spitzner Franziska
Department of Cytology and Evolutionary Biology, Zoological Institute and Museum, University of Greifswald, Greifswald, Germany.
Methods Mol Biol. 2020;2047:253-270. doi: 10.1007/978-1-4939-9732-9_14.
Micro-computed X-ray tomography (μCT) coupled with visualization techniques such as three-dimensional reconstruction of internal morphological structures has opened up new pathways for analyzing the anatomy of nervous systems in intact specimens. The possibility for combining μCT with other techniques is one of the major advantages of μCT scanning, and the technical development of higher resolutions in lab-based μCT-scanners allows for investigating the anatomy of specimens in the sub-milimeter range. The European shore crab Carcinus maenas features a larval development over four zoeal and one megalopal stage with body lengths ranging from 500 μm to 2000 μm. The developing nervous system in the larvae of C. maenas is organized into a central brain which is connected via esophageal connectives with a ventral nerve chord and segmental ganglia. Since soft tissues such as the nervous tissues feature low contrasts compared to other tissues such as muscles or cuticularized body parts, the interpretation in μCT scans is challenging and needs some practice. The protocol described here is also applicable for larger specimens of a variety of species and spans over 2-3 days resulting in an image stack ready for postprocessing and visualization.
微计算机断层扫描（μCT）与内部形态结构三维重建等可视化技术相结合，为分析完整标本中的神经系统解剖结构开辟了新途径。μCT与其他技术相结合的可能性是μCT扫描的主要优势之一，实验室μCT扫描仪更高分辨率的技术发展使得在亚毫米范围内研究标本的解剖结构成为可能。欧洲滨蟹（Carcinus maenas）的幼虫发育经历四个蚤状幼体阶段和一个大眼幼体阶段，体长从500微米到2000微米不等。欧洲滨蟹幼虫发育中的神经系统由一个中枢脑组成，该中枢脑通过食管连接与腹神经索和节段神经节相连。由于神经组织等软组织与肌肉或角质化身体部位等其他组织相比对比度较低，因此在μCT扫描中的解读具有挑战性，需要一些实践经验。这里描述的方案也适用于各种物种的较大标本，整个过程需要2至3天，最终得到一个可供后处理和可视化的图像堆栈。
