Cardiac morphogenesis requires an intricate orchestration of mechanical stress to sculpt the heart as it transitions from a straight tube to a multichambered adult heart. Mechanical properties are fundamental to this process, involved in a complex interplay with function, morphology, and mechanotransduction. In the current work, we propose a pressurization technique applied to the zebrafish atrium to quantify mechanical properties of the myocardium under passive tension. By further measuring deformation, we obtain a pressure-stretch relationship that is used to identify constitutive models of the zebrafish embryonic cardiac tissue. Two-dimensional results are compared with a three-dimensional finite element analysis based on reconstructed embryonic heart geometry. Through these steps, we found that the myocardium of zebrafish results in a stiffness on the order of 10 kPa immediately after the looping stage of development. This work enables the ability to determine how these properties change under normal and pathological heart development.

心脏形态发生需要复杂的机械应力协调来塑造心脏，因为它从直管过渡到多腔成人心脏。机械特性是这一过程的基础，涉及与功能、形态和机械转导的复杂相互作用。在目前的工作中，我们提出了一种应用于斑马鱼心房的加压技术，以量化被动张力下心肌的机械特性。通过进一步测量变形，我们获得了压力-拉伸关系，用于识别斑马鱼胚胎心脏组织的本构模型。二维结果与基于重建胚胎心脏几何结构的三维有限元分析进行比较。通过这些步骤，我们发现斑马鱼的心肌在发育的循环阶段后立即导致 10 kPa 的刚度。这项工作能够确定这些特性在正常和病理性心脏发育下如何变化。