胎児性アルコール症候群の成長・発達におよぼす豊環境の影響に関する実験的研究

Abstract

Objective : To clarify effects of rich environment on growth and development in experimental fetal alcohol syndrome.Material and Methods : Jcl-ICR mice whose mothers were injected with 5g / kg of 30% ethanol intraperitoneally on the 9th day of pregnancy (AL gr.) were compared with equivalent distilled water groups (C gr.). After weaning, each group were divided in rich environment namely, group-housing with play instruments (ALR gr. And CR gr.) and standard environment (ALS gr. And CS gr.). Growth and development including motor reflex, open-field test and radial maze learning were followed and compared between each group. Brains were examined histologically at 5 hours after the injection of ethanol by electron microscope and myelinogenesis on the 60th postnatal days by Klüver-Barrera method were compared between each group.Results : 1) On the 9th day of pregnancy, electron-lucent vacuoles of mitochondrias in the matrix cells of the AL gr. Fetuses were demonstrated by the electron microscope. Brain myelination was statistically less than that of C gr. At 40 and 60 days of age. 2) Growth and motor reflexes during 0-20th postnatal days in AL gr. Mice were less than those in C gr. Mice. 3) In the open-field test, the means of crossing number in outer layer, rearing and grooming numbers at 40 days of age in ALR gr. Were higher than those of ALS gr.. However, environmental effects in AL gr. At the 40 days of age were disappeared at the 60 days of age. 4) In the radial maze, the mean number of correct choices of ALR gr. Were higher than that of CR gr. CS gr. And ALS gr. With significant differences. Conclusion : Effects of rich environment on behavioral development were clarified by the use of several parameters in AL gr..