Techniques for perfusion and storage of heterotopic heart transplants in mice

Organ pretreatment prior to transplantation has assumed increasing importance. We studied the ability to preserve and perfuse hearts in well-defined genetic mouse models, prior to heterotopic engraftment. Hearts were manually perfused through the aortic root and stored in a variety of cold solutions or were perfused using a continuous perfusion pump. Different electrolyte solutions, mouse strains, perfusion, and storage times as well as perfusion volumes were studied. Treated hearts were than transplanted heterotopically and short- and long-term function assessed. Hearts stored for more than 1 hour in cold solutions (saline 0.9%, or lactated Ringer's) failed to function. Hearts perfused with 0.25-0.4 ml of cold solution for a maximum of 30 minutes functioned well after transplantation. C3H (H-2k) mice provided the most resilient hearts. We conclude that short-term perfusion or storage of mouse hearts is feasible and should provide an excellent model for the study of organ pretreatment with monoclonal antibodies or other agents prior to transplantation.