ASTUDY ON THE EFFECTS OF RETINOIC ACID ON THE DEVELOPMENT OF THE ALBINO RAT CEREBELLAR CORTEX

Abstract

A total number of 50 albino rats were used in this study. 30 of them were studied using light microscopy and were stained by Einarson's gallocyanin stain. 15 of them were . control offsprings of non treated mothers and 15 were offsprings of mothers subjected to retinoic acid from the eleventh to the thirteenth day of gestation. The rats were sacrificed at the ages of newborn, five, ten days, fifteenth days and twenty one days. The other 20 rats were divided into two groups ten offsprings of non treated mothers and ten offsprings of mothers treated with retinoic acid on the eleventh day of gestation, then they were studied by electron microscopy. The results indicated that retinoic acid; (although an oxidative metabolite of vitamin A) nevertheless it may cause a variety of cellular changes in the cerebellum, especially if the pregnant mother was subjected to it in its period of sensitivity. At light microscopic level, the results reveal that there was clumping of granule cells, together with heavy staining and relative decrease in the thickness of its layer compared to the control. Regarding the Purkinje cell layer, it presented areas of focal losses in different ages together with distortion of its cells and separation found at this layer between it and the internal granular layer.