Abstract: 【Objective】 To observe the effects of marginal vitamin A deficiency during pregnancy on the lung' morphology of fetal rats. 【Methods】 Prenatal vitamin A normal(VAN)and marginal vitamin A deficiency(MVAD)of Sprague-Dawley rat models were employed.There were 6 mice in each group.On the gestational day 19,fetal rats were harvested by cesarean section.Then weighed their body,lung and liver.The fetal lung morphology were observed by light microscope after hematoxylin and eosin stain.The vitamin A concentrations of lung were detected by high-performance liquid chromatography(HPLC),and the levels of retinoic acid receptor(RAR)mRNAs were detected by semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR),then the values of RAR mRNAs were compared to glyceraldehyde-3-phosphate dehydrogenase(GAPDH)mRNA. 【Results】 1)The weights of fetals'body,lung and liver in VAN group were higher than those of MVAD group(P<0.05).2)By light microscope(high and lower power lens),the fetal lung morphology were better developed in VAN group than MVAD group.In VAN group,alveolar-like structure were better-arranged,and alveolar septums were thinner.They were rich in blood capillary among the interstitial tissue.They were canalicular period;but MVAD group were gland period.3)Compared with the two groups,the vitamin A concentrations of lungs in VAN group were higher than those of MVAD group(P<0.05).4)The levels of RAR and mRNA in VAN group were lower than those of MVAD group(P<0.05). 【Conclusions】 The weights of fetals' body,lung and liver,the fetal lung morphology,the vitamin A concentrations of lungs and the levels of RAR and mRNA are all influenced by vitamin A level during pregnancy.The fetal lung whose mother are vitamin A deficiency during pregnancy are worse developed.

Key words: vitamin A, lung, morphology, retinoic acid receptor, fetal rats

摘要： 【目的】 探讨孕期亚临床维生素A(vitamin A,VA)缺乏对胎鼠肺形态发育的影响。 【方法】 建立孕期VA正常(vitamin A normal,VAN)和亚临床缺乏(marginal vitamin A deficiency,MVAD)动物模型,每组均于孕19 d剖宫取胎鼠,比较其体重、肺重、肝重和肺组织VA含量及其肺视黄酸受体(retinoic acid receptor,RAR)mRNAs的表达,HE染色光镜观察胎鼠肺的形态结构。 【结果】 1)胎鼠基本情况的比较 体重、肺重和肝重三个指标VAN组均显著高于MVAD组(P<0.05);2)胎肺大体形态比较 低倍镜(×200)与高倍镜(×400)下观察结果显示,VAN组肺泡样结构分布较规则,肺泡间隔较薄,肺实质发育较好,肺间质毛细血管较丰富,肺泡2型细胞较明显,大多处于小管期;而MVAD组上述指标均相对较差,发育幼稚,局部为小管期,大多为假腺体期;3)胎鼠肺单位组织VA水平 VAN组>MVAD组,差异均有统计学意义(P<0.05);4)胎鼠肺RAR-α、RAR-γ和RAR-β mRNAs表达水平VAN组<MVAD组,三个基因的表达水平两组比较差异均有统计学意义(P<0.05)。 【结论】 孕期VA水平不同能影响胎鼠基本发育、胎肺形态结构、肺单位组织VA水平及其RAR mRNAs的表达;孕期MVAD时其胎肺发育相对较差。

关键词: 维生素A, 肺, 形态, 视黄酸受体, 胎鼠