Cold preservation of the porcine pancreas with histidine-tryptophan-ketoglutarate solution

Background. Histidine-tryptophan-ketoglutarate (HTK) has been used for experimental and clinical cardiac, renal, and liver transplantation. No experience exists in either experimental or clinical pancreas transplantation. Methods. In the present study, the solution was employed to flush segmental pancreatic grafts and to autotransplant the grafts after 24, 48, and 72 hr of cold storage in a porcine model. The results were compared to those obtained from animals receiving pancreatic grafts flushed and preserved with UW (University of Wisconsin) solution. Results. A total of 10 landrace pigs received a graft stored with HTK solution for 24 hr, and 6 animals received a graft stored with UW solution for 24 hr. Daily blood glucose levels were normoglycemic (i.e., blood glucose <150 mg/dl), and glucosuria was absent in all transplant animals. Intravenous glucose tolerance tests were comparable to two unoperated controls. Seven totally pancreatectomized, nontransplant diabetic controls exhibited daily hyperglycemia, glucosuria (i.e., >1,000 mg/dl) and highly impaired intravenous glucose tolerance tests (mean K-values of -0.52+/-0.19 vs. -1.25+/-0.46 for HTK, -1.30+/-0.81 for UW, and -1.53+/-0.81 for controls, P-value vs. diabetic <0.01). The changes in wet weight between flushing and reperfusion were +2.22+/-2.84 g for HTK and -1.40+/-2.70 g for UW stored grafts (P=0.034). After 48 hr of storage with HTK, 4/17 grafts were functioning and 1/11 recipients of grafts stored with UW were normoglycemic. All grafts stored for 72 hr in either HTK (n=3) or UW (n=3) uniformly failed to render the recipients normoglycemic. Conclusions. It is concluded that preservation of segmental pancreatic autografts for 24 hr with HTK solution provides reliable graft function, as does preservation with UW solution associated with an increase in wet weight after HTK preservation. Cold preservation with HTK and UW is feasible for 48 hr; however, the success rate is equally reduced with HTK and UW solution. Cold storage for 72 hr in either HTK or UW solution results in uniform graft failure in this model.