Abstract
Peripheral nerves of the diabetic insulin-dependent BB-Wistar-rat were studied ultrastructurally. Conspicuous early changes consisted of mitochondrial accumulation of glycogen in the axons and the development of honey-combed Schwann cell-axon networks. The later stages of the diabetic syndrome showed axonal dwindling and disintegration in both myelinated and unmyelinated fibers. The present findings are compared with those of other experimental diabetic models.