A novel technique for heterotopic vascularized pancreas transplantation in mice to assess ischemia reperfusion injury and graft pancreatitis.

BACKGROUND: Although various suture techniques for murine pancreas transplantation have been described, severe limitations have limited their widespread use. We therefore designed a surgical model for cervical heterotopic pancreas transplantation using a cuff technique.
METHODS: C57BL6 mice were used as donor and recipient pairs. Recipients were rendered diabetic with streptozotocin and subsequently transplanted. The donor pancreas was isolated using a no-touch technique and then placed in the recipient's cervical region. Vascular anastomoses were completed by pulling the portal vein over the external jugular vein cuff and the donor aortic segment over the carotid cuff and fixed with an 8-0 ligature thereby facilitating a nonsuture technique. To test applicability of this model, graft microcirculation was evaluated by intravital microscopy after prolonged cold ischemia (16 h).
RESULTS: The immediate success rate was >90%. Donor operation lasted 40 +/- 5 min; dissection of recipient vessels lasted 20 +/- 4 min. Revascularization time was 4 to 6 min, resulting in a total pancreas ischemia time of 33 +/- 6 min. No thromboembolic complications on the cuff side were observed. Preoperative glucose levels were 518 +/- 59 mg/dl and returned to normal by postoperative day 1 (88 +/- 13 mg/dl). Histology on postoperative days 10 and 30 showed almost normal islet cell and acinar architecture of all grafts. In groups with prolonged cold ischemia, graft microcirculation was significantly reduced and paralleled by increased inflammation, interstitial edema, hemorrhage, acinar vacuolization, and focal areas of necrosis compared with nonischemic controls.
CONCLUSIONS: This new model may provide an excellent tool to further investigate the pathophysiology as well as novel therapeutic strategies of preservation, ischemia reperfusion injury, and graft pancreatitis.