Effects of tissue impregnation and extraction of dimethylsulfoxide in low-temperature preservation of dog small intestine

The aim of this study, directed toward the low-temperature preservation of dog small intestine, was to determine the most satisfactory conditions of use of the cryophylactic agent dimethylsulfoxide (DMSO). Earlier preservation experiments performed on isolated intestinal loops have shown that after rewarming and extraction of this cryophylactic substance by perfusion, an important edema had taken place. This led us to investigate the conditions of its appearance and to search for means to suppress or reduce it. Using a technique similar to that described by Cady et al. (5) in their study of dog kidney glycerolization, the experimental principle of which consists in observing variations in weight of the organ as a function of time and various perfusion methods, the following results have been obtained: 1. 1. The origin of the edema is of an osmotic nature and it appears principally during the extraction phase of the cryophylactic agent. 2. 2. The magnitude of the edema is a function of the concentration of DMSO in the impregnation perfusate, and of the duration of the impregnation phase. 3. 3. The effectiveness of the substance under study, at least in regard to the edema, is improved when: (a) DMSO is used at a relatively low concentration (about 10% v v ); (b) tissue impregnation time of the cryophylactic agent is short (