Pregnancy Sub-clinical Vitamin A Deficiency And With Antenatal Dexamethasone On Fetal Lung

PARTⅠTHE EFFECTS OF MARGINAL VITAMIN A DEFICIENCY DURING PREGNANCY ON THE LUNG OF FETAL RATSObjective: To observe the effects of marginal vitamin A deficiency during pregnancy on the lung of fetal rats.Methods: Prenatal vitamin A normal(VAN)and marginal vitamin A deficiency ( MVAD ) of Sprague-Dawley rat models were employed.There were 3 in each group.From the gestational days 16 to 18 , all the rats were given Saline by intramuscular injection respectively.On the gestational day 19,fetal rats were harvested by cesarean section.Then recorded the weighs of their body,lung and liver . The vitamin A concentrations of lung were detected by high-performance liquid chromatography(HPLC),and the levels of pulmonary surfactan(tPS)and retinoic acid recepto(rRAR)mRNAs were detected by semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR);then the values of PS and RAR mRNAs were compared to glyceraldehyde-3-phosphate dehydrogenase ( GAPDH ) mRNA.Results:(1)The weighs of fetal rats'body,lung and liver were lower in MVAD group than those in VAN group.There were significant differences among the two groups(P<0.05);(2)The vitamin A concentrations of lungs in MVAD group were lower than those in VAN group . There were significant differences among the two groups(P<0.05);(3)As to the levels of SP-B and SP-C mRNAs, they were lower in MVAD group than those in VAN group.There were significant differences between the two group(sP<0.05).(4)With regard to the levels of RAR mRNA,the levels of RAR-αand RAR-γmRNAs lower in VAN group than in MVAD group.The levels of RAR-βmRNA in the two groups were similar to those of the RAR-αand RAR-γmRNAs. And There were significant differences(P<0.05).Conclusion : The basic body build of fetal rat , vitamin A concentrations of lungs and the levels of SP-B and SP-C mRNAs,the levels of RAR mRNA,were all influenced by marginal vitamin A deficiency during pregnancy.The fetal lungs of the MVAD's mother is immature. PARTⅡTHE EFFECTS OF PRENATAL DEXAMETHASONE AND MARGINAL VITAMIN A DEFICIENCY DURING PREGNANCY ON THE LUNG OF FETAL RATSObjective:To observe the effects of prenatal dexamethasone(Dex)and marginal vitamin A deficiency during pregnancy on the lung of fetal rats.Methods:Prenatal vitamin A normal(VAN)and marginal vitamin A deficiency(MVAD)of Sprague-Dawley rat models were employed.There were 3 in each group.From the gestational days 16 to 18,all the rats were given dexamethasone by intramuscular injection respectively.On the gestational day 19,fetal rats were harvested by cesarean section.Then recorded the weighs of their body,lung and liver.The vitamin A concentrations of lung were detected by high-performance liquid chromatography(HPLC),and the levels of pulmonary surfactant(PS)and retinoic acid receptor ( RAR ) mRNAs were detected by semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR);then the values of PS and RAR mRNAs were compared to glyceraldehyde-3-phosphate dehydrogenase(GAPDH)mRNA.Results:(1)The weighs of fetal rats'body,lung and liver were lower in MVAD-Dex group than those in VAN-Dex group,lower inVAN-Dex than those in VAN-NS group,and lower in MVAD-Dex group than those in MVAD-NS group.There were significant differences among the two groups(P<0.05);(2)The vitamin A concentrations of lungs were higher in VAN-Dex group than those in VAN-NS group,higher in MVAD-Dex group than those in MVAD-NS group,and higher in VAN-Dex group than those in MVAD-Dex group,There were significant differences among the two groups(P<0.05);(3)As to the levels of SP-B and SP-C mRNAs,they were higher in MVAD-Dex group than those in MVAD-NS group,there was significant differences between the two groups(P<0.05).The levels in VAN-Dex group were higher than those in VAN-NS group,higher in VAN-Dex group than those in MVAD-Dex group,but there were no significant differences between the four groups(P>0.05);(4)With regard to the levels of RAR mRNA,the levels of the three receptors'mRNAs were higher inVAN-Dex group than those in VAN-NS group,higher in MVAD-Dex group than those in MVAD-NS group,and lower inVAN-Dex group than those in MVAD-Dex group , there were significant differences between the six groups(P<0.05)Conclusion:When there was marginal vitamin A deficiency during pregnancy and glucocorticosteroid were applicated,the basic body build of fetal rat were relatively weak,but the vitamin A concentrations of lungs were aslo significantly rised.So did the levels of SP-B mRNAs and SP-C mRNAs and the levels of RAR mRNA. But the effects of Dex to maturation of fetal lung will not be affected.