Vladimir Gluhovic, Sara Timm, Wolfgang M Kuebler, Elena Lopez-Rodriguez, Matthias Ochs
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引用次数: 0
Abstract
The alveolar surface of the lung is lined by an epithelium consisting of type I (AECI) and type II alveolar epithelial cells (AECII). This epithelium is covered by a liquid alveolar lining layer (ALL). Besides intra-alveolar surfactant, ALL also contains the alveolar epithelial glycocalyx on the apical side of AECI and AECII. To better understand the alveolar epithelial glycocalyx, its ultrastructural visualization by transmission electron microscopy is required. The aim of this study was to systematically re-evaluate routine cytochemical methods for visualization of the alveolar epithelial glycocalyx and specifically its glycan components. For this purpose, we used chemical fixation by vascular perfusion with aldehydes as a common routine approach in mice. After fixation, staining is needed for glycocalyx visualization. Cytochemical staining agents such as alcian blue, ruthenium red, and lanthanum nitrate were compared. In addition, SNL (Sambucus nigra lectin) and UEA1 (Ulex europaeus agglutinin I) were used for sialic acid and fucose-specific labeling. Alcian blue showed the strongest staining, with cloud-like structures, whereas ruthenium red appeared as thread-like structures. On the other hand, lanthanum nitrate did not stain the alveolar epithelial glycocalyx. For specific sialic acid and fucose labeling, both lectins presented a specific signal. In conclusion, these methods can be used routinely for assessing ultrastructural changes of the alveolar epithelial glycocalyx in experimental in vivo models under different physiological and pathological conditions. In addition, cytochemical staining by tissue massage and post-embedding lectin labeling after vascular perfusion support 3R (reduction, refinement, replacement) principles of animal welfare.
期刊介绍:
Journal of Anatomy is an international peer-reviewed journal sponsored by the Anatomical Society. The journal publishes original papers, invited review articles and book reviews. Its main focus is to understand anatomy through an analysis of structure, function, development and evolution. Priority will be given to studies of that clearly articulate their relevance to the anatomical community. Focal areas include: experimental studies, contributions based on molecular and cell biology and on the application of modern imaging techniques and papers with novel methods or synthetic perspective on an anatomical system.
Studies that are essentially descriptive anatomy are appropriate only if they communicate clearly a broader functional or evolutionary significance. You must clearly state the broader implications of your work in the abstract.
We particularly welcome submissions in the following areas:
Cell biology and tissue architecture
Comparative functional morphology
Developmental biology
Evolutionary developmental biology
Evolutionary morphology
Functional human anatomy
Integrative vertebrate paleontology
Methodological innovations in anatomical research
Musculoskeletal system
Neuroanatomy and neurodegeneration
Significant advances in anatomical education.