Tellurium-induced myelinopathy in adult rats.

Tellurium is known to induce a neuropathy in young rats but not in adult rats. In the present study adult rats were fed a diet containing 1.25% tellurium every day for 30 days. By the end of this period, the rats moved with difficulty but did not show paralysis. Study of teased nerve fiber preparations in conjunction with light and electron microscopy revealed myelin abnormalities consisting of myelin bubbling, segmental demyelination, and remyelination. In some animals, these abnormalities had a patchy distribution, affecting several adjoining nerve fibers in sciatic nerves, brachial plexus, and spinal roots. The intramyelinic edema sometimes was associated with splitting of the axons.