大量维生素A影响鼠胚眼发育的研究

ULTRASTURCTURAL AND HISTOCHEMICAL STUDY IN EFFECTS OF FXCESS VITAMIN A ON THE PRENATAL DEVELOPMENT OF THE RAT'S EYES

本文应用光镜、透射镜、扫描电镜、组织化学和免疫组织化学,观察了10～20天鼠胚眼的发育及大量维生素A对鼠眼发育的影响。结果,引起了鼠眼的各部畸形。认为,此乃大剂量维生素A引起鼠眼的间充质缺乏,眼发育过程诱导作用减弱所致。

Thirty-eight pregnant wistar rats were divided into one control group and three experimental groups freely.On the 8th, 9th,and 10th day of gestation,30,60,and 90mg of the vitamin A were administered orally to the pregnant rats of three experimental groups, group 1, 2 and 3,respectively. The fetuses were removed on the 10th, 11th,12th, 13th, 14th,17 th and 20th day of gestation respectively, and then examined for external malformation,and examined further with light microscope, histochemistry,TEM and SEM. The results showed external malformations including exencephaly, microphthalmia, cleftpalate,anophthalmia,ete.in the experimental group 2 and 3. The histological examination of the eyes revealed degeneration changes in the cornea,lens and retina in the experimental groups.the activities of the alkaline phosphatase and adenosinetriphosphtase in the control group were higher than those in the experimental groups.Transmission Electron Microscopy indicated that in the control group the multilamellar corpuscles of pigment epithelial cell may be the predecessor of the melanin granules. In the experimental groups mitochondria and endoplasmic reticula became irregular in shape and fragmented. Scanning Elec tron microscopy indicated that in the control group the sorts of the cornea anterior epithelium cells and protrusions of the retina increased gradually with the days of embryos going by.In experimental groups the layers of the retina became thin and the protrusion of the retina decreased appartently.The significance of these phenomenon were discussed in the article.