Salinas Samuel D, Clark Margaret M, Amini Rouzbeh
Department of Biomedical Engineering, The University of Akron, Akron, OH 44325, USA.
Bioengineering (Basel). 2019 Aug 15;6(3):70. doi: 10.3390/bioengineering6030070.
Since many soft tissues function in an isotonic in-vivo environment, it is expected that physiological osmolarity will be maintained when conducting experiments on these tissues ex-vivo. In this study, we aimed to examine how not adhering to such a practice may alter the mechanical response of the tricuspid valve (TV) anterior leaflet. Tissue specimens were immersed in deionized (DI) water prior to quantification of the stress-strain responses using an in-plane biaxial mechanical testing device. Following a two-hour immersion in DI water, the tissue thickness increased an average of 107.3% in the DI water group compared to only 6.8% in the control group, in which the tissue samples were submerged in an isotonic phosphate buffered saline solution for the same period of time. Tissue strains evaluated at 85 kPa revealed a significant reduction in the radial direction, from 34.8% to 20%, following immersion in DI water. However, no significant change was observed in the control group. Our study demonstrated the impact of a hypo-osmotic environment on the mechanical response of TV anterior leaflet. The imbalance in ions leads to water absorption in the valvular tissue that can alter its mechanical response. As such, in ex-vivo experiments for which the native mechanical response of the valves is important, using an isotonic buffer solution is essential.
由于许多软组织在体内等渗环境中发挥功能，因此预计在对这些组织进行体外实验时将维持生理渗透压。在本研究中，我们旨在研究不遵循这种做法如何改变三尖瓣（TV）前叶的机械反应。在使用平面双轴机械测试装置对组织标本的应力-应变反应进行量化之前，将其浸入去离子（DI）水中。在DI水中浸泡两小时后，DI水组的组织厚度平均增加了107.3%，而对照组仅增加了6.8%，在对照组中，组织样本在相同时间段内浸没在等渗磷酸盐缓冲盐溶液中。在85 kPa下评估的组织应变显示，浸入DI水后，径向应变从34.8%显著降低至20%。然而，对照组未观察到显著变化。我们的研究证明了低渗环境对TV前叶机械反应的影响。离子失衡导致瓣膜组织吸水，从而改变其机械反应。因此，在瓣膜天然机械反应很重要的体外实验中，使用等渗缓冲溶液至关重要。
