维生素A缺乏对小鼠胚胎Hox基因表达的影响

目的：观察维生素Ａ（ＶＡ）缺乏对小鼠胚胎ＨｏｘＣ４（３．５）和ＨｏｘＤ１０（４．５）基因表达量的影响。方法：初断乳的昆明小鼠，雌鼠４０ 只均分为正常对照组（Ａ）和维生素Ａ缺乏组（Ｂ），分别饲含ＶＡ４０００ ＩＵ／ｋｇ 饲料和ＶＡ ０ ＩＵ／ｋｇ 饲料。雄鼠饲以普通饲料。在饲养的第１７ 周按雌∶雄＝ ２∶１ 合笼交配。在怀孕的第１２ 天和第１４ 天，分别对孕鼠颈椎脱臼处死，立刻剖腹取出胎鼠，迅速置于液氮中速冻后置于－ ７０℃冰箱保存。用地高辛标记的探针，采用原位杂交方法探测小鼠胎儿ＨｏｘＣ４（３．５）和ＨｏｘＤ１０（４．５）基因ｍ ＲＮＡ含量。结果：ＶＡ缺乏时，ｍ ＲＮＡ的含量明显减少。结论：ＶＡ缺乏导致Ｈｏｘ 基因表达量下降，从而影响小鼠胚胎的正常发育。

THE EFFECTS OF VITAMIN A DEFICIENCY ON HOX GENES EXPRESSION IN MOUSE EMBRYOS

To investigate the effects of vitamin A deficiency on Hox3.5 and Hox4.5 genes expression in mouse embryos. Methods: Forty Kunming female mice were divided into two groups: normal group A (4000 IU VA/kg diet) and VA deficiency group B (0 IU VA/kg diet). After 17 weeks feeding, the mice were made to copulate (female∶male=2∶1). On the 12th and 14th day p.c. (post coitus), 6 pregnant mice in group A and 6 in group B were killed respectively, and the mouse embryos were taken out immediately. In situ hybridization was used to determine the content of mRNA of Hox3.5 and Hox4.5 genes in the mouse embryos by digoxigenin labeled cDNA probes. Results: The contents of Hox3.5 and Hox4.5 genes mRNA in the embryos of group B decreased significantly compared with group A (P<0.01). Conclusion: It is suggested that decreased Hox genes expression by vitamin A deficiency may influence the normal development and growth of mouse embryos.