NEUROPATHY IN DIABETIC BB WOR RATS TREATED WITH INSULIN IMPLANTS/

To elucidate the pathophysiology of diabetic neuropathy many workers h ave examined nerve specimens from diabetic rats. While most workers fo und that animals with high blood glucose levels develop neuropathy, so me researchers report that the peripheral nerves are normal in hypergl ycaemic rats. Hypoglycaemia may also cause neuropathy. Some workers su ggest that neuropathy is linked to fluctuations of the blood glucose l evel. In the present study we examine plantar nerves of diabetic BB/Wo r rats maintained on an eu-/hyperglycaemic or an eu-/hypoglycaemic reg ime with insulin implants. Treatment with implants worked well. Light microscopic examination of nerve fibres in non-diabetic control rats a nd in eu-/hyperglycaemic diabetic rats showed a normal picture. Prepar ations from eu-/hypoglycemic rats showed irregular myelin sheaths and signs of Wallerian degeneration. The lengths and diameters of the larg est internodes were significantly subnormal. We conclude, that periodi c moderate hypoglycaemia, but not periodic moderate hyperglycaemia, el icits neuropathy in diabetic BB/Wor rats treated with insulin implants .