title: [Localization and quantitative analysis of insulin-like growth factor-I in placenta of extreme fetus].
abstract: OBJECTIVE
  To investigate the immunohistochemical localization of insulin-like growth factor-I (IGF-I) in human placenta and to evaluate the role of IGF-I in fetal growth and placental growth.
  
  
  METHODS
  In 72 tested samples, The cellular distribution of IGF-I in human placenta was determined by using immunohistochemistry. The relative area and mean absorbance were determined by using image analysis technique. Student's t-test was used to compare mean values between groups.
  
  
  RESULTS
  IGF-I immunostaining was found in syncytiotrophoblast, cytotrophoblast and Hoffbauer's cells of chorionic villi and chorion of fetal membranes. The strongest immunoreactivity was observed in the syncytiotrophoblast and cytotrophoblast. The relative area and absorbance in placenta of SGA group were significantly lower than those of AGA group respectively (t = 4.65, P < 0.001; t = 2.15, P < 0.05). But the relative arca and absorbance of LGA were significantly higher than those of AGA (t = 8.72, P < 0.001; t = 7.82, P < 0.001).
  
  
  CONCLUSIONS
  These results suggested that IGF-I in human placenta was principally synthsized and secreted by syncytiotrophoblast, cytotrophoblast, hoffbauer's cells of chorionic villi and chorion of fetal membranes. IGF-I is an improtant regulator of fetal and placental growth and development. It has the key role for macrosomia and IUGR forming.
authors.affiliation: First Affiliated Hospital, Nanjing Medical University.
authors.forename: G
authors.initials: G
authors.lastname: Wan
authors.forename: J
authors.initials: J
authors.lastname: Leng
authors.forename: S
authors.initials: S
authors.lastname: Yu
mesh_terms: D000328:Adult; D005314:Embryonic and Fetal Development; D005260:Female; D005320:Fetal Macrosomia; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D010920:Placenta / Q000737:chemistry*; D010929:Placentation; D011247:Pregnancy
chemical_list: D007334:Insulin-Like Growth Factor I