Prevention by whole pancreas transplantation of glomerular basement membrane thickening in alloxan diabetes.

Serial thickness measurements of the glomerular basement membrane were performed over a 24-month period in four groups of inbred male Lewis rats. Group I consisted of normal animals age-matched to the remaining experimental groups. In groups II, III, and IV, diabetes was induced by intravenous alloxan (42 to 44 mg/kg). Group II was subsequently untreated. One week after induction of diabetes, groups III and IV received vascularized isografts of the pancreas and duodenum or duct-ligated pancreas alone, respectively. Animals in all groups were killed monthly and X 11,000 electron photomicrographs prepared of the kidney. The thickness of the glomerular basement membrane was measured by a quantitative morphometric technique. Untreated diabetic animals developed significant thickening of the basement membrane when compared to normal animals and the differences remained significant throughout life. Animals undergoing pancreas transplantation were completely protected from the diabetic changes in the basement membrane and showed no increase in basement membrane thickness when compared to normal animals. Pancreaticoduodenal and duct-ligated isografts offered equal protection against changes in the basement membrane. All groups showed age-related thickening of the basement membrane; this change was accelerated in the untreated diabetic group and normalized in the transplanted rats.