摘要
目的:研究维生素A(VA)缺乏及补充对大鼠胚胎后脑Hoxa-2和Hoxb-2mRNA表达的影响。方法:初断乳SD雌性大鼠60只,按体重随机分为VA缺乏组(A),VA缺乏妊娠0d(E0)补充组(B)和正常对照组(N)。A组和B组喂饲VA缺乏饲料,B组自E0天起改喂VA补充饲料(含VA10000IU/kg饲料),N组喂饲VA充足饲料(含VA4000IU/kg饲料),雄鼠饲以普通饲料。喂饲7w后采集尾血,将雌雄大鼠2︰1合笼交配,分别于妊娠D12.5(E12.5)和妊娠D19.5(E19.5)将孕鼠处死,留取血标本,剖腹取出胚胎。用微量荧光法测定母鼠血清中VA含量;观察E12.5和E19.5胚胎存活情况,记录活胎数、死胎数及吸收胎数;并用半定量逆转录聚合酶链反应(RT-PCR)检测E12.5胚胎组织Hoxa-2、Hoxb-2mRNA的表达。结果:与N组相比,A组孕鼠血清VA水平下降;E12.5和E19.5胚胎的存活率显著降低,死胎及吸收胎的发生率增加,E12.5胚胎Hoxa-2、Hoxb-2mRNA表达水平明显下降;B组孕鼠各项指标同正常组相比无显著性差异。结论:胚胎后脑发育基因Hoxa-2、Hoxb-2可能介导VA对大鼠胚胎存活的影响。
Objective： To investigate the effects of vitamin A （VA） on embryonic survival via induction of Hoxa-2 and Hoxb-2 mRNA expression. Method： Weanling female SD rats were fed VA-deficient diet or VA-supplemented diet for 7 w to develop marginal VA-deficient model or control. After mating, pregnant marginal VA-deficient mice were fed VA-deficient or VA-supplement diets starting at embryonic day 0 （E0）. Serum VA concentration was determined by spectrofluorimetric micromethod. Embryonic survival at E12.5 and E19.5 was examined. By reverse transcription polymerse chain reaction （RT-PCR） technique the expression levels of Hoxa-2 and Hoxb-2 mRNA in hindbrain at E12.5 were detected. Results： Serum VA concentration, the number of live embryos and expression levels of Hoxa-2 and Hoxb-2 mRNA were reduced significantly than those of control group, while the number of dead and resorbed embryos were increased significantly. There was no difference of these parameters in VA-supplement group starting at E0 compared with control group. Conclusion： The essential role of VA in embryonic survival is possibly attributed to the induction of Hoxa-2 and Hoxb-2 mRNA expression in embryonic hindbrain at E12.5.
出处
《营养学报》
CAS
CSCD
北大核心
2007年第4期352-355,358,共5页
Acta Nutrimenta Sinica
基金
国家自然科学基金(No.30471460)
