Long-term function of duct-ligated and free-duct whole pancreas transplants

Comparison of graft morphology and endocrine function after vascularized whole-pancrease transplantation in the rat by different surgical techniques

Graft morphology and endocrine function following vascularized pancreas transplantation by different surgical techniques were determined in streptozotocin-diabetic rats. Eight different surgical techniques were studied. Intestinal drainage of exocrine secretion was accomplished by pancreaticoduodenal transplantation or by utilizing only a patch of the donor duodenum for duodenojejunostomy. Following pancreaticoureterostomy and pancreaticocystostomy, the graft's exocrine secretion was drained to the recipient's urinary tract. The exocrine secretion was allowed to drain freely into the recipient's peritoneal cavity following transverse or longitudinal incision of the common bile duct. Exocrine secretion was suppressed either by duct ligation or by retrograde ductal injection of prolamine. Following enteric or urinary exocrine graft drainage, the architecture of both the endocrine and exocrine pancreas was perfectly preserved. Pancreatic juice had remarkably few adverse effects on the recipient's urinary tract. Obstruction of the exocrine secretion induced atrophy of the acinar cells, proliferation of small pancreatic ducts, and a typical fragmentation of the islets of Langerhans. Prolamine was biologically degraded within 28 days. Following free intraperitoneal drainage, spontaneous suppression of the exocrine graft function occurred early after transplantation. Metabolic signs of diabetes mellitus including hypoinsulinemia, hyperglycemia, polydipsia, polyuria, and impaired glucose tolerance were completely normalized by pancreas transplantation irrespective of the surgical technique used. Despite fundamental differences in graft architecture no alteration of endocrine graft function was noted following vascularized pancreas transplantation by different surgical techniques.

Long-term studies of pancreas allotransplantation in experimental diabetes mellitus

Pancreaticoduodenal (PD) allografts (Brown Norway-alloxan-diabetic rats, n = 190) were treated with cyclosporin A (Cy-A) 10 mg/kg/daily and compared with nondiabetics with Cy-A treatment (n = 55), diabetics (n = 50), and diabetics with Cy-A treatment (n = 45). Body weight, blood sugar, blood insulin, blood urea nitrogen (BUN), and creatinine were monitored periodically; there were marked elevations of BUN and creatinine levels, indicating probably nephrotoxicity of Cy-A at this dosage. Some islet cell atrophy in the PD allografts was noted at the conclusion of the study. With respect to the immunosuppressive effect of Cy-A in alloxan diabetic rats, Brown Norway PD transplants into Lewis rats were successful and free of rejection for as long as 15 months post-transplantation. The body weight of these PD transplanted rats, however, never approached values representative of the nondiabetic rats. In our experience, the PD allograft model is acceptable in the clinical situation, particularly in children if the microsurgical technique is mastered and if the Cy-A regimen is used in combination with other immunosuppressant(s).