Department of Pharmacology, University of California, Davis School of Medicine, Davis, California (J.T., M.N.-C., M.F.N., C.Y.K., D.M.B.).
Department of Anatomy, Physiology, and Genetics, University of Oxford, Oxford, UK (J.T.).
Circ Res. 2023 Sep;133(6):450-462. doi: 10.1161/CIRCRESAHA.123.322847. Epub 2023 Aug 9.
Calcium (Ca) sparks are elementary units of subcellular Ca release in cardiomyocytes and other cells. Accordingly, Ca spark imaging is an essential tool for understanding the physiology and pathophysiology of Ca handling and is used to identify new drugs targeting Ca-related cellular dysfunction (eg, cardiac arrhythmias). The large volumes of imaging data produced during such experiments require accurate and high-throughput analysis.
We developed a new software tool SparkMaster 2 (SM2) for the analysis of Ca sparks imaged by confocal line-scan microscopy, combining high accuracy, flexibility, and user-friendliness. SM2 is distributed as a stand-alone application requiring no installation. It can be controlled using a simple-to-use graphical user interface, or using Python scripting.
SM2 is shown to have the following strengths: (1) high accuracy at identifying Ca release events, clearly outperforming previous highly successful software SparkMaster; (2) multiple types of Ca release events can be identified using SM2: Ca sparks, waves, miniwaves, and long sparks; (3) SM2 can accurately split and analyze individual sparks within spark clusters, a capability not handled adequately by prior tools. We demonstrate the practical utility of SM2 in two case studies, investigating how Ca levels affect spontaneous Ca release, and how large-scale release events may promote release refractoriness. SM2 is also useful in atrial and smooth muscle myocytes, across different imaging conditions.
SparkMaster 2 is a new, much-improved user-friendly software for accurate high-throughput analysis of line-scan Ca spark imaging data. It is free, easy to use, and provides valuable built-in features to facilitate visualization, analysis, and interpretation of Ca spark data. It should enhance the quality and throughput of Ca spark and wave analysis across cell types, particularly in the study of arrhythmogenic Ca release events in cardiomyocytes.
钙火花是心肌细胞和其他细胞亚细胞钙释放的基本单位。因此，钙火花成像技术是理解钙处理生理学和病理生理学的重要工具，用于识别靶向与钙相关的细胞功能障碍的新药（例如，心律失常）。在这种实验中产生的大量成像数据需要准确和高通量的分析。
我们开发了一种新的软件工具 SparkMaster 2（SM2），用于分析共聚焦线扫描显微镜成像的钙火花，具有高精度、灵活性和用户友好性。SM2 作为独立应用程序分发，无需安装。它可以使用简单易用的图形用户界面进行控制，也可以使用 Python 脚本进行控制。
SM2 具有以下优点：（1）在识别钙释放事件方面具有很高的准确性，明显优于以前非常成功的软件 SparkMaster；（2）SM2 可以识别多种类型的钙释放事件：钙火花、波、迷你波和长火花；（3）SM2 可以准确地分裂和分析火花簇内的单个火花，这是以前的工具无法充分处理的功能。我们在两个案例研究中展示了 SM2 的实际用途，研究了钙水平如何影响自发性钙释放，以及大规模释放事件如何促进释放不应期。SM2 在心房和平滑肌心肌细胞中，在不同的成像条件下也很有用。
SparkMaster 2 是一种新的、改进的用户友好软件，用于准确、高通量地分析线扫描钙火花成像数据。它是免费的，易于使用，并提供了有价值的内置功能，以方便钙火花和波数据的可视化、分析和解释。它应该提高细胞类型的钙火花和波分析的质量和通量，特别是在研究心肌细胞中的致心律失常钙释放事件方面。
