Cao-Ehlker Xiaochun, Fischer Carola, Lu Kun, Bruegmann Tobias, Sasse Philipp, Dendorfer Andreas, Tomasi Roland
Walter Brendel Centre of Experimental Medicine, University Hospital, Ludwig-Maximilians-Universität Munich, 81377 Munich, Germany.
Department of Cardiac Surgery, University Hospital, Ludwig-Maximilians-Universität Munich, 80636 Munich, Germany.
Bioengineering (Basel). 2023 Jan 28;10(2):171. doi: 10.3390/bioengineering10020171.
Organotypic heart slices from mice might provide a promising in vitro model for cardiac research because of the vast availability of genetically modified specimens, combined with the unrestricted feasibility of experimental interventions. However, murine heart slices undergo rapid degeneration in culture. Therefore, we developed optimal conditions to preserve their structure and function in culture. Mouse ventricular heart samples were transversely cut into 300 µm thick slices. Slices were then cultured under various conditions of diastolic preload, systolic compliance and medium agitation. Continuous stimulation was performed either by optical stimulation or by electrical field stimulation. Contractility was continuously measured, and cellular survival, structure and gene expression were analyzed. Significant improvements in viability and function were achieved by elastic fixation with the appropriate diastolic preload and the rapid shaking of a ß-mercaptoethanol-supplemented medium. At 1 Hz pacing, mouse heart slices maintained stable contractility for up to 48 h under optogenetic pacing and for one week under electrical pacing. In cultured slices, the native myofibril structure was well preserved, and the mRNAs of myosin light chain, titin and connexin 43 were constantly expressed. Conclusions: Adult murine heart slices can be preserved for one week and provide a new opportunity to study cardiac functions.
由于基因改造样本丰富，且实验干预不受限制，小鼠的器官型心脏切片可能为心脏研究提供一个有前景的体外模型。然而，小鼠心脏切片在培养过程中会迅速退化。因此，我们开发了在培养中保存其结构和功能的最佳条件。将小鼠心室心脏样本横向切成300 µm厚的切片。然后将切片在不同的舒张期预负荷、收缩期顺应性和培养基搅拌条件下进行培养。通过光刺激或电场刺激进行持续刺激。持续测量收缩性，并分析细胞存活、结构和基因表达。通过适当的舒张期预负荷进行弹性固定以及快速摇晃添加了β-巯基乙醇的培养基，可显著提高活力和功能。在1 Hz起搏下，小鼠心脏切片在光遗传学起搏下可保持稳定收缩性长达48小时，在电起搏下可保持一周。在培养的切片中，天然肌原纤维结构保存良好，肌球蛋白轻链、肌联蛋白和连接蛋白43的mRNA持续表达。结论：成年小鼠心脏切片可保存一周，并为研究心脏功能提供了新机会。
