Diabetic neuropathy in STZ-induced diabetic rat and effect of allogeneic islet cell transplantation. Morphometric analysis.

The effect of pancreatic islet cell allotransplantation on the development of diabetic neuropathy in streptozocin-induced diabetic ACI rats was examined morphometrically with light- and electron-microscopic procedures. Peripheral nerve function was evaluated by nerve conduction velocity and evoked muscle potential amplitude measurements. Diabetes was induced at 4 mo of age, and diabetic animals were transplanted by intracerebral and intraportal grafts 2 wk later. Diabetic animals with accepted grafts returned to euglycemia and showed a normal body-weight gain over the subsequent 14-mo observation period. Transplanted animals with accepted grafts and those in whom graft rejection was induced were compared with age-matched nontransplanted diabetic rats and nondiabetic control rats at 18 mo of age. Successful allotransplantation completely prevented axonal atrophy and the characteristic nodal and paranodal structural abnormalities in diabetic nerve, as well as the typical slowing of nerve conduction velocity. Our data suggest that islet cell allotransplantation is an effective therapeutic approach to the prevention of diabetic neuropathy.