CONSIDERABLE effort is being expended on devising means of storing kidneys extracorporeally in anticipation of homotransplantation. The work of Semb1 and associates has shown that the metabolism of renal slices decreases exponentially with falling temperature. It is well documented that two hours is the maximal tolerance of the canine kidney to ischemia at body temperature.
In theory, the lower the environmental core temperature, the longer is the organ's ischemic tolerance. However, at 0 C, the barrier of freezing damage has to be surmounted. Lovelock2 expounded the hypothesis that freezing produces extracellular ice crystallization, and that these crystals are formed at the expense of intracellular water with the result that the cells die of dehydration ("hypertonic cellular damage").
Many techniques for avoiding such damage are recorded in the literature. One is the use of an endocellular cryophylactic agent. Dimethyl sulfoxide was first used for this purpose by Lovelock and