Cold preservation of rat pancreatic islets just above the freezing point using University of Wisconsin solution

Aims: To confirm whether rat islets stored at a temperature just above the freezing point using University of Wisconsin (UW) solution would remain via ble for the short term. Methodology: Rat islets were stored for 24 hours in UW solution, either at 4 degreesC or at -0.6 degreesC (just above the specific freezing point of t he UW solution). After cold storage, the islets were assessed for in vitro viability by static incubation and for in vivo viability by a transplantati on study. One thousand islets preserved under different conditions were inj ected intraportally into a streptozotocin-induced diabetic rat as an isogra ft. Four weeks after the transplantation, an intravenous glucose tolerance test was performed. Results: Islets stored at -0.6 degreesC showed higher insulin secretion rat es than those stored at 4 degreesC on a static challenge. The interval from transplantation to the achievement of normoglycemia was also shorter in th e -0.6 degreesC group than in the 4 degreesC group. After islet transplanta tion, the daily nonfasting plasma glucose concentration was higher in the 4 degreesC group than in the -0.6 degreesC group. When compared with the 4 d egreesC group, the -0.6 degreesC group showed lower blood glucose values du ring all investigational periods on an intravenous glucose tolerance test. Conclusion: Islet preservation at -0.6 degreesC using UW solution is more a dvantageous for short term.