A method of analysis is described which evaluates the biochemical and physiological status of kidneys after preservation experiments and identifies the injury of preservation in a numerical way. These methods have been applied to the study of freezing injury in kidneys through experimental efforts to freeze slices of intact renal cortex in a viable state. Successful freezing as measured in this assay system has not yet been accomplished, but differing patterns of improvement have been seen after cryoprotection with 15% dimethyl sulfoxide and after eryoprotection plus control of freezing rate at -1°C per min. In addition, kidney cortex tolerates 15% DMSO without measurable injury. The techniques of in vitro analysis have been shown to be applicable to the further study of freezing of intact tissue and organs and will be helpful in the solution of the problems in at least two of three major areas involved in the successful freeze preservation of whole organs. © 1969.
