The effect of vitamin E (1 g/kg body weight) supplementation on myosin-V and neuronal nitric oxide synthase (nNOS) immunoreactive
myenteric neurons from the ileum of diabetic rats was investigated in the present study. Forty animals were divided into the
following groups: normoglycemics (N), normoglycemics treated with vitamin E (NE), diabetics (D), and diabetics treated with
vitamin E (DE). Quantitative and morphometric analyses were performed. The area of the tertiary plexus was also determined.
Diabetes produced a 24% reduction in the number of myosin-V neurons in group D compared with group N, an effect that was accompanied
by an increase in the tertiary plexus area (
P < 0.05). Neuronal density was 27% higher in group NE than group N (
P < 0.05). Nitrergic neuronal density was not altered as a consequence of either diabetes or vitamin E treatment. Myosin-V
and nNOS immunoreactive neuronal cell body area increased significantly in group NE. The area of myosin-V and nNOS myenteric
neurons also increased in group D. Vitamin E treatment (group DE) increased only the size of nitrergic neurons. The present
results suggest that vitamin E elicited a neuroprotective and neurotrophic effect on the natural aging process, but with regard
to diabetes, vitamin E supplementation exerted a neurotrophic effect only on nitrergic neurons.
Keywords Diabetes mellitus - Myenteric neurons - Myosin-V - Neuronal nitric oxide synthase - Vitamin E