Alterations in Retrograde Axonal Transport in Streptozocin-Induced Diabetic Rats

Retrograde axonal transport in the sciatic nerve of rats with streptozocin-induced diabetes was studied by the [³H]N-succinimidyl propionate ([³H]NSP) method. The accumulation of retrogradely transported labeled proteins in the dorsal root ganglia and the ventral horn of spinal cord 1 day after [³H]NSP injection was not statistically significantly different from controls in rats diabetic for 1 or 14 days at the time of [³H]NSP injection. However, accumulation of labeled proteins in the dorsal root ganglia 7 days after [³H]NSP injection was reduced by 35% and transport to the ventral horn of spinal cord 7 days after [³H]NSP injection was reduced by 70% at the same time points. Partial control of the diabetes with insulin resulted in a partial reversal of these deficits. The early occurrence of defects in retrograde transport suggests that such defects may play a role in the pathogenesis of the neuropathy.