Stereological Examination of Effects of Ethanol on Optic Nerve in Experimental Alcohol Model

Abstract

The objective of the present study was to perform histological and stereological examination of alcohol-induced changes in the optic nerve, considered an extension of white matter of the brain, in rats. This study included 20 male Wistar albino rats aged 60 days and weighing 190-220 g. The rats were divided into three groups: ethanol (n = 7), maltodextrin (n = 7), and control (n = 6) groups. The ethanol group was administered ethanol at a dose of 6.4% (v/v) instead of water for 18 days; the maltodextrin group received maltodextrin for the same time period, and the control group was the sham group. At the end of the experiment, a 0.5-mm long section of the optic nerve starting from the optic chiasma was dissected and examined with routine microscopic histological examination methods. The modified Cavalieri method was used for stereological measurement. Total tissue area ratios were calculated with a point grid provided by the Shtereom 1.5 software package. The statistical comparison of the groups revealed that the ethanol group had a significant reduction in the number of axons and sheath area of the optic nerve compared to the control and maltodextrin groups (p < 0.017, p < 0.022, respectively). These results indicate the toxic effects of ethanol on the optic nerve.