['Investigate the effect of dietary vitamin E (Vit E) on the retinas of a rat model of induced glaucoma, in which surgically induced elevation of intraocular pressure (IOP) is associated with an increase in reactive oxygen species.', 'Rats were fed a standard chow, Vit E-supplemented diet, or Vit E-deficient diet and subjected to surgically induced IOP elevation (or sham surgery) for five weeks. The retinal ganglion cells (RGCs) were subjected to retrograde fluorescent tracer labeling.', 'The mean number of RGCs of rats on the standard chow, Vit E-supplemented diet, and Vit E-deficient diet were 79.6%, 78.6%, and 71.3% of controls, respectively. Lipid peroxidation of the retinas of rats given a Vit E-deficient diet were significantly higher after IOP elevation for three days (14.42 +/- 0.25 microM, P = 0.016) and five weeks (10.46 +/- 0.11 microM, p = 0.042), compared to rats given standard chow (11.37 +/- 0.31 microM; 8.95 +/- 0.16 microM). Compared with rats given standard chow, rats given a Vit E-deficient diet had significantly elevated concentrations of glutathione (p = 0.032), but no significant differences in the levels of total superoxide dismutase (SOD), Cu/Zn SOD, or catalase activities three days after IOP elevation.'] Does dietary deficiency of vitamin E aggravate retinal ganglion cell death in experimental glaucoma of rats?