Since the discovery of functional brown adipose tissue (BAT) in adult humans, research on BAT gained a new popularity to combat obesity and related comorbidities. To date, however, methods to quantify BAT thermogenesis are often either highly invasive, require advanced equipment, are time consuming or of limited sensitivity. Here we present a simple yet highly effective and minimally invasive protocol for the Precise Unravelment of Non-shivering brown fat thermoKinetics (PUNK) in mice using infrared thermography in combination with Vaseline to brush up the fur between the shoulder blades. We also use physiological and molecular readouts including indirect calorimetry, qPCR and Western Blots to test our protocol. Our study demonstrates that Vaseline before thermography vastly advances the reproducibility and quality of BAT infrared pictures or videos, as it exposes the skin above the BAT for a direct line of sight for the infrared camera and thereby circumvents the well-known problems associated with shaving and anaesthesia. We subsequently validate that this approach does not affect physiological and molecular BAT function, but instead leads to more robust and less variable results when comparing for instance norepinephrine stimulation tests or knockout animals. Taken together, the PUNK protocol for BAT thermography quickly and effectively improves scientific outcomes of this method, and can be easily added to existing paradigms. Consequently, it safes money, time and experimental animals, thereby putting the 3R’s principles of animal welfare into practice.

自从在成人中发现功能性棕色脂肪组织 (BAT) 以来，对 BAT 的研究在对抗肥胖和相关合并症方面获得了新的欢迎。然而，迄今为止，量化 BAT 产热的方法通常要么是高度侵入性的，要么需要先进的设备，要么耗时，要么灵敏度有限。在这里，我们提出了一种简单而高效且微创的协议，用于使用红外热像仪与凡士林结合刷洗肩胛骨之间的毛皮，精确解开小鼠的非颤抖棕色脂肪热动力学 (PUNK)。我们还使用生理和分子读数，包括间接量热法、qPCR 和蛋白质印迹来测试我们的协议。我们的研究表明，热成像前的凡士林极大地提高了 BAT 红外图像或视频的再现性和质量，因为它使 BAT 上方的皮肤暴露在红外相机的直接视线范围内，从而避免了与剃须和剃须相关的众所周知的问题。麻醉。我们随后验证了这种方法不会影响生理和分子 BAT 功能，而是在比较例如去甲肾上腺素刺激试验或基因敲除动物时产生更稳健且变化更少的结果。总之，用于 BAT 热成像的 PUNK 协议快速有效地提高了该方法的科学成果，并且可以轻松添加到现有范例中。因此，它可以保护金钱、时间和实验动物，