Morphological study of nervous system in Vacor-induced diabetic rats.

Patients with Vacor diabetes mellitus frequently developed diabetic ketoacidosis and neuropathy in the early stage of the disease; however, the mechanism of the development of diabetes and its neurologic complications is not known. In this study, oral administration of 100 mg Vacor/kg of body weight was used in Wistar male rats. The rats were sacrificed 6 h after administration to avoid natural expiration. Light microscopy revealed focal hemorrhage and edematous change in the periventricular area of the brain, scattered hemorrhage in the posterior and anterior horns, spongy degeneration and demyelinization in th fasciculus gracilis and cuneatus of the white matter, early degenerative changes in the sciatic nerve, and no change of the vagus. Electron microscopy showed necrosis of the axon, myelin sheaths and glia cells in the spinal cord, while the organelles of the peripheral nerves were unchanged. These findings indicate that Vacor produces various neurotoxicities in the acute toxic phase.