School of Biomedical Sciences, Kent State University;
School of Biomedical Sciences, Kent State University.
J Vis Exp. 2022 Jul 27(185). doi: 10.3791/64264.
Skeletal muscle thermogenesis provides a potential avenue for better understanding metabolic homeostasis and the mechanisms underlying energy expenditure. Surprisingly little evidence is available to link the neural, myocellular, and molecular mechanisms of thermogenesis directly to measurable changes in muscle temperature. This paper describes a method in which temperature transponders are utilized to retrieve direct measurements of mouse and rat skeletal muscle temperature. Remote transponders are surgically implanted within the muscle of mice and rats, and the animals are given time to recover. Mice and rats must then be repeatedly habituated to the testing environment and procedure. Changes in muscle temperature are measured in response to pharmacological or contextual stimuli in the home cage. Muscle temperature can also be measured during prescribed physical activity (i.e., treadmill walking at a constant speed) to factor out changes in activity as contributors to the changes in muscle temperature induced by these stimuli. This method has been successfully used to elucidate mechanisms underlying muscle thermogenic control at the level of the brain, sympathetic nervous system, and skeletal muscle. Provided are demonstrations of this success using predator odor (PO; ferret odor) as a contextual stimulus and injections of oxytocin (Oxt) as a pharmacological stimulus, where predator odor induces muscle thermogenesis, and Oxt suppresses muscle temperature. Thus, these datasets display the efficacy of this method in detecting rapid changes in muscle temperature.
骨骼肌产热为更好地理解代谢稳态和能量消耗的机制提供了一个潜在途径。令人惊讶的是，很少有证据将产热的神经、肌细胞和分子机制直接与肌肉温度的可测量变化联系起来。本文描述了一种利用温度传感器直接测量小鼠和大鼠骨骼肌温度的方法。将遥测传感器通过手术植入小鼠和大鼠的肌肉中，然后给动物时间恢复。必须让小鼠和大鼠反复适应测试环境和程序。然后，在其巢箱中对药物或环境刺激做出反应来测量肌肉温度的变化。在规定的体育活动（例如，以恒定速度在跑步机上行走）期间也可以测量肌肉温度，以排除活动变化对这些刺激引起的肌肉温度变化的影响。该方法已成功用于阐明大脑、交感神经系统和骨骼肌水平上肌肉产热控制的机制。本文提供了使用捕食者气味（PO；雪貂气味）作为环境刺激和催产素（Oxt）注射作为药物刺激来证明这一成功的示例，其中捕食者气味诱导肌肉产热，而 Oxt 抑制肌肉温度。因此，这些数据集显示了该方法在检测肌肉温度快速变化方面的有效性。
