No abstract

The effects of chronic ethanol consumption during gestation on the development of layer V pyramidal cells was studied quantitatively in the somatosensory cerebral cortex of the newborn guinea-pig. The spread of the basilar dendritic arborizations and counts of dendritic spines on the apical dendrite of neurons that had been processed with the rapid Golgi method were compared with those found in age-matched controls receiving an isocaloric diet without alcohol. There were significant differences in the number of primary basilar dendrites (P less than 0.05) and dendritic ramifications at a distance of 25 micron from the soma (P less than 0.01) between the alcohol-exposed and control animals. There also were significant differences in the number of dendritic spines on the apical dendrite (P less than 0.001). This experimental model further illustrates developmental anomalies in the cerebral cortex following prenatal ethanol exposure.

No abstract

When processed by the rapid Golgi method, a significant reduction (P less than 0.002) of the dendritic arborization of Purkinje cells located at the tips of the folia of the rostral vermis was demonstrated in four human cases of cerebellar atrophy, related to chronic alcohol consumption. Except for isolated damaged Purkinje cells located on the depth of the sulci of the rostral vermis in all but one case, no significant differences were observed between alcoholic cases and controls of comparable ages among Purkinje cells located in the remainder of the vermis or the cerebellar hemispheres. These results suggest that structural changes, which precede neuronal death and cell loss, are present in Purkinje cells of the rostral vermis in human cerebellar alcoholic degeneration.

To increase our understanding of the effects of chronic ethanol consumption beginning at adolescence, 25% ethanol in drinking water (v/v) was administered daily to young rats aged 45-50 days for 5 months. Increased numbers of dendritic spines on the apical dendrite of layer V pyramidal neurons of the somatosensory cortex (U-Mann-Whitney test, P less than 0.01-0.05) were found in almost every 50-micron-long segment over a distance of 500 microns from the cell body in ethanol-treated rats at the age of 195-200 days when compared with age-matched controls. Although the mechanisms leading to this unusual finding are not know, it is suggested that impairment of the naturally occurring elimination of redundant synapses can not be ruled out.