Determination of the Amounts of Ice Formed in the Feet of Mice Frozen at Various Temperatures

摘要

The amount of ice formed in amputated feet of mice frozen at various temperatures was found, in 26 calorimetric determinations, to vary from 29.6% of the total weight at -1.5C to 46.7% at -9.5C. These figures represent, respectively, 46% and 72.5% of the water content of the limb. The average deviations from the mean percentage of ice per total weight were of the order of three units. The proportions of water frozen at given temperatures, after establishing equilibrium of ice formation, are appreciably lower in these experiments than in those of Lovelock and Smith on the hamster. There is close similarity in the ratios of electric capacitances of nonfrozen and frozen paws of mice, in the cases of amputated limbs, attached limbs in dead animals and attached limbs in living animals. This similarity justifies the use of calorimetric determinations made on amputated limbs to estimate the amounts of ice formed in living tissues or organs frozen under the same conditions, as furnished by the ratios of capacitances, after the relationship between these ratios and the calorimetric data is established. (Author)