Measurement of heat production in skeletal muscle with HgCdTe infrared detector.

使用热电堆测量收缩过程中的热产生，以获得关于肌肉收缩中化学机械转换的机制的信息。在热电堆实验中，有一些假设，肌肉的所有局部区域都以相同的方式对机械和热做出反应。热电堆可以获得肌肉收缩过程中沿肌肉长轴产生的热量的信息，但不可能在肌肉的局部区域做到这一点。目前尚不清楚(1)强直肌肉局部的产热时间进程是否与整个肌肉的产热时间进程相同。(2)静息状态下肌肉表面的温度分布情况，以及等长破伤风后肌肉表面温度的变化情况。(3)等长破伤风产生的局部热与同一区域机械反应的关系。我们用碲镉汞红外探测器搭建了热测量装置，并用热像仪对上述问题进行了研究。将青蛙缝纫肌(Rana Catesbeiana)原位固定在支架上，用多个金属细小标记，等长拉伸2-5秒。用热电堆测量的3个热速分量的肌肉中心局部区域的产热时间进程与整个肌肉区域的产热时间进程相同。静息和强直肌肉中的温度分布在整个肌肉长度上是不均匀的。一般情况下，靠近骨盆端和中央部的局部区域通过伸展靠近胫骨末端的区域有缩短的趋势，并且前者在等长性破伤风时的产热量大于后者。这些结果表明，在等长性破伤风过程中，局部的热和机械反应在整个肌肉长度上并不是一致的。

Measurements of heat production during contraction have been performed by use of a thermopile to obtain information about the mechanism of chemomechanical conversion in muscle contraction. In the thermopile experiment, there is some assumption that all the local region of muscle respond mechanically and thermally in the same manner. It is possible to obtain information about heat produced along the long axis of muscle during muscle contracion by the thermopile, but not possible to do that in the local region of muscle. It is unknown (1) whether time course of heat production in the local region of tetanized muscle is same as that in the whole region. (2) how thermal distribution on the muscle surface in the resting muscle is shown, and how it changes immediately after isometric tetanus. (3) how local heat produced during isometric tetanus relates to mechanical response of the same region.We constracted heat measurement apparatus by use of HgCdTe infrared detector and used a thermography to investigate above questions. Frog sartorius muscle (Rana catesbeiana) was mounted to the holder at in situ length with several metal fine markers and isometrically tetanized for 2-5 sec. Time course of heat production in central local region of muscle was same as that in whole region of muscle measured by the thermopile with 3 heat rate components. Thermal distributions in the resting and tetanized muscle were non-uniform along the entire length of muscle. In general, the local regions near pelvic end and central part tended to shorten by stretching those near the tibial end, and the amount of heat production during isometric tetanus was larger in the former thanin the latter. These result indicate that the local thermal and mechanical responses during isometric tetanus are not uniform along the entire length of the muscle.