Injury Caused by the Formation of Ice in the Isolated Muscles of Rats

摘要

Previous investigations showed that the feet of mice and rats can recover completely after having been exposed in the frozen state at -10C for 10 and 20 minutes. In the present work, a study was made of the ability of a single excised component of the rat limb, namely the tibialis anticus muscle, to survive freezing. The muscle, coated with vaseline and carrying an inserted thermal junction, was immersed directly into a bath at -3, -5 or -10C. When the internal temperature had dropped to -2C, the muscle was seeded (to initiate ice formation) and maintained in the frozen state for various lengths of time. It was rewarmed by abrupt transfer to a water bath at +35C and tested for its ability to contract when electrically stimulated. In baths at -3C the muscles survived 40 to 45 minutes in the frozen state, with 40 to 45% of the water transformed into ice. In baths at -5C they survived 15 minutes but not 20 minutes, with about 55% of the water frozen. Nor survival was obtained in muscles kept frozen for even only one minute at -10C, when some 70% of the water was frozen. (Author)