Fetal alcohol syndrome and mental retardation: spine distribution of pyramidal cells in prenatal alcohol-exposed rat cerebral cortex; a Golgi study.

Among the various possible effects of the fetal alcohol-syndrome (FAS), mental retardation can be considered the most deleterious. In animal studies, prenatal alcohol exposure has been shown to result in increased neonatal mortality, retarded cerebellar development and a significant decrease in neonatal brain weight. In a Golgi study on Wistar rats that were prenatally exposed to alcohol the spine distribution in proximal apical dendrites of layer V pyramidal cells of the parietal cortex was examined. As compared with controls, a distinct spine abnormality could be demonstrated at 12 days and at 40 days of postnatal age: a persistent predominance of long, thin and entangled spines, and a decreased number of normal stubby and mushroom-shaped spines. These abnormal dendritic patterns show a striking resemblance to those described by Purpura in mentally retarded children of normal karyotype.