title: [Effects of maternal deficiency of folic acid during pregnancy on pulmonary development and SP-A expression in newborn rats].
abstract: OBJECTIVE
  This study examined the effects of maternal deficiency of folic acid during pregnancy on pulmonary development and protein A (SP-A) expression in newborn rats in order to explore the possible mechanism of lung developmental disorders.
  
  
  METHODS
  Thirty-six adult Sprague-Dawley female rats were randomly assigned into two groups: control and study (n=18). The study and the control groups were fed with fodder containing folic acid or not respectively. Two weeks later, the female rats in the two groups copulated with normal male rats. Newborn rats were sacrificed at 1, 7 and 14 days after birth (8 pups at each time point). Lung sections were stained with hematoxylin and eosin for histological examination. SP-A expression of protein and mRNA were determined by immunohistochemistry and real-time quantitative RT-PCR, respectively.
  
  
  RESULTS
  The newborn rats from the study group showed damaged lung tissue structures. The mean optical density of type II cells with positive expression of SP-A decreased significantly from 1 to 14 days in newborn rats of the study group compared with the control newborn rats (P<0.05). The real-time quantitative RT-PCR showed that the expression of lung SP-A mRNA also decreased significantly from 1 to 14 days in newborn rats of the study group compared with control newborn rats (P<0.05).
  
  
  CONCLUSIONS
  Maternal deficiency of folic acid during pregnancy can decrease the expression of SP-A in lung tissues of newborn rats, which might lead to the disorder of lung development maturation.
authors.affiliation: Department of Pediatrics, Nanjing Maternal and Child Health Hospital Affiliated to Nanjing Medical University, Nanjing 210004, China.
authors.forename: Li-Xing
authors.initials: LX
authors.lastname: Qiao
authors.forename: Zhang-Bin
authors.initials: ZB
authors.lastname: Yu
authors.forename: Shu-Ping
authors.initials: SP
authors.lastname: Han
authors.forename: Xiao-Qi
authors.initials: XQ
authors.lastname: Gu
authors.forename: Yu-Lin
authors.initials: YL
authors.lastname: Chen
authors.forename: Li
authors.initials: L
authors.lastname: Sha
authors.forename: Jun-Xia
authors.initials: JX
authors.lastname: Jin
authors.forename: Lu-Biao
authors.initials: LB
authors.lastname: Yan
authors.forename: Xi-Rong
authors.initials: XR
authors.lastname: Guo
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D005260:Female; D005494:Folic Acid Deficiency / Q000378:metabolism*; D007150:Immunohistochemistry; D008168:Lung / Q000196:embryology*; D008297:Male; D011247:Pregnancy; D011248:Pregnancy Complications / Q000378:metabolism*; D037662:Pulmonary Surfactant-Associated Protein A / Q000032:analysis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D037662:Pulmonary Surfactant-Associated Protein A; D012333:RNA, Messenger