Granillo Alejandro, Pena Celia A, Pham Thuy, Pandit Lavannya M, Taffet George E
Huffington Center on Aging, Baylor College of Medicine.
Pulmonary/Critical Care/Sleep Medicine, Michael E. DeBakey Veterans Affairs Medical Center.
J Vis Exp. 2017 Feb 20(120):55214. doi: 10.3791/55214.
The present methodology teaches the investigator how to measure and use the LAV as a surrogate of chronic elevations in Left Ventricular diastolic pressure through echocardiography, as well as to obtain measurements of the Aorta and PA diameter in mice. Mice older than 10 d of age can be analyzed using the present technique. The technique is composed of 3 main steps: set-up, image acquisition, and image analysis. The set-up step consists of getting the mouse anesthetized with 1% isoflurane, shaving it, and taping it in a supine position to a heated EKG board where the image acquisition will take place. The image acquisition step consists of learning to identify the cardiac structures and obtaining all the required images with its correspondent probe and axis in order to be able to calculate volumes and diameters. The image analysis step consists of measuring the previously acquired images with the aid of computer software. Advantages of the proposed technique include a fast (15 min) procedure that would allow the researcher to evaluate interventions in a non-invasive, non-terminal approach and therefore follow the same mouse over time; each mouse can be used as its own control. This fact plus having the same operator perform all the acquisition and analysis for the entire experiment minimizes the limitation of operator-dependency. The present methodology is useful for mouse researchers in cardiovascular and pulmonary medicine.
目前的方法教导研究人员如何通过超声心动图测量和使用左房容积(LAV)作为左心室舒张压慢性升高的替代指标,以及如何获取小鼠主动脉和肺动脉直径的测量值。10日龄以上的小鼠可以使用本技术进行分析。该技术由3个主要步骤组成:设置、图像采集和图像分析。设置步骤包括用1%异氟醚麻醉小鼠、剃毛,并将其仰卧位固定在加热的心电图板上,在该板上进行图像采集。图像采集步骤包括学会识别心脏结构,并用相应的探头和轴获取所有所需图像,以便能够计算容积和直径。图像分析步骤包括借助计算机软件测量先前采集的图像。所提出技术的优点包括快速(15分钟)的程序,这将使研究人员能够以非侵入性、非终末的方法评估干预措施,因此可以随时间跟踪同一只小鼠;每只小鼠都可以作为自身对照。这一事实加上由同一名操作人员对整个实验进行所有采集和分析,最大限度地减少了操作人员依赖性的限制。本方法对心血管和肺部医学领域的小鼠研究人员很有用。