Department of Basic Veterinary Science, Laboratory of Physiology, The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan.
Laboratory of Veterinary Physiology, Faculty of Applied Biological Sciences, 1-1 Yanagido, Gifu, 501-1193, Japan.
J Physiol Sci. 2021 Mar 30;71(1):10. doi: 10.1186/s12576-021-00794-1.
The aim of the present study was to establish a novel method for inducing deep hypothermia in rats. Cooling rats anesthetized with isoflurane caused a time-dependent decrease in rectal temperature, but cardiac arrest occurred before their body temperature reached 20 °C when isoflurane inhalation was continued during the cooling process. Stopping inhalation of isoflurane when the rectal temperature reached 22.5 °C successfully induced deep hypothermia, although stopping the inhalation at 27.5 °C resulted in spontaneous recovery of rectal temperature. The hypothermic condition was able to be maintained for up to 6 h. A large number of c-Fos-positive cells were detected in the hypothalamus during hypothermia. Both the maintenance of and recovery from hypothermia caused organ injury, but the damage was transient and recovered within 1 week. These findings indicate that the established procedure is appropriate for inducing deep hypothermia without accompanying serious organ injury in rats.
本研究旨在建立一种诱导大鼠深度低温的新方法。用异氟烷麻醉大鼠并进行冷却会导致直肠温度随时间下降，但当在冷却过程中继续吸入异氟烷时，其体温在达到 20°C 之前会发生心脏骤停。当直肠温度达到 22.5°C 时停止吸入异氟烷可以成功诱导深度低温，尽管在 27.5°C 时停止吸入会导致直肠温度自发恢复。低温条件可以维持长达 6 小时。在低温期间，在下丘脑中检测到大量的 c-Fos 阳性细胞。低温的维持和恢复都会导致器官损伤，但损伤是短暂的，并在 1 周内恢复。这些发现表明，所建立的程序适合诱导大鼠深度低温，而不会伴随严重的器官损伤。
