Increased Number of Dorsal Root Ganglion Neurons in Vitamin-E-Deficient Rats

Quantitative and morphometric observations were carried out on neurons of L₃-L₆ dorsal root ganglia (DRGs) in control and vitamin-E-deficient rats at different ages. Controls were fed a standard diet and sacrificed at 1 or at 5 months of age; deficient rats were fed a diet without vitamin E from 1 to 5 months of age and then sacrificed. No significant difference in total number of neurons was found, but an increase in neuron sizes, a decrease in nucleus-cytoplasm ratio, and a more circular neuron shape were found in controls with increasing age (from 1 to 5 months). In L₃-L₆ DRGs of vitamin-E-deficient rats (5 months of age), a higher number of neurons was found than in those of either young or adult controls. Moreover, some morphometric characteristics of neurons in the deficient rats were similar to those of neurons in 1-month-old controls. The findings suggest that vitamin E deficiency can trigger events resulting in appearance of new neurons, possibly anticipating phenomena that normally occur in aging.