754 Observation of microscopic deformation of porcine thoracic aortas during stretch in their thin sliced sections
Details
Arterial walls consist of structural components that have various elastic moduli: elastin, collagen, and smooth muscle cells (SMCs). Such difference in their mechanical properties may cause their heterogeneous deformation at a microscopic level in arterial tissue subjected to uniform deformation at a macroscopic level. To examine this hypothesis, we slice 20-50-μm-thick specimens from aortic tissue, and stretch them under a transmitted light microscope to observe deformation of their inner structure caused by macroscopic deformation. We need to freeze specimens to obtain such thin slices, which normally kill SMCs in the tissue. To keep the cells alive during freezing procedure, we found an optimal freezing condition with the use of a cryoprotectant, dimethylsulfoxide. Additionally, we observed deformations of cell nuclei during stretch of an aortic specimen to find that cell nuclei were not only stretched, but also rotated. Each of SMCs in the wall might deform in a complex manner in response to uniform deformation given at a macroscopic level.
