title: The effects of folic acid in the prevention of neural tube development defects caused by phenytoin in early chick embryos.
abstract: METHODS
  The effects of phenytoin and folic acid on the development of neural tube defects in early chick embryos were studies.
  
  
  OBJECTIVE
  To investigate the effects of folic acid in the prevention of neural tube development defects.
  
  
  BACKGROUND
  Several studies have shown that phenytoin selectively inhibits neural tube closure. Folic acid supplementation has been reported to decrease the occurrence of neural tube defects.
  
  
  METHODS
  This study shows the effects of folic acid in preventing neural tube development defects caused by phenytoin in chicks based on light microscopy, transmission electron microscopy, and histopathological examination. Forty-five fertile Hubbard Broil eggs, all at Stage 8 (four somite) of development, were divided into three equal groups: Group 1 embryos (n = 15), the control group, were explanted and grown for 18 hours in a nutrient medium (thin albumin). Group 2 embryos (n = 15) were explanted and grown for 18 hours in a nutrient medium containing 500 microg/mL of phenytoin. Group 3 embryos (n = 15) were explanted and grown for 18 hours in a nutrient medium containing 500 microg/mL of phenytoin and 0.4 microg/mL of folic acid.
  
  
  RESULTS
  After the incubation period, 86.6% of the control embryos (Group 1) had intact neural tubes; 80% of Group 2 and 46.6% of Group 3 embryos showed neural tube defects.
  
  
  CONCLUSIONS
  The results of this study suggest that phenytoin causes neural tube defects, whereas folic acid decreases the incidence of neural tube development defects caused by phenytoin in early chick embryos.
authors.affiliation: Department of Neurosurgery, Selçuk University Medical School, Konya, Turkey. oguney@doctor.com
authors.forename: Onder
authors.initials: O
authors.lastname: Güney
authors.forename: Aydan
authors.initials: A
authors.lastname: Canbilen
authors.forename: Abdullah
authors.initials: A
authors.lastname: Konak
authors.forename: Osman
authors.initials: O
authors.lastname: Acar
mesh_terms: D000818:Animals; D002642:Chick Embryo; D005492:Folic Acid / Q000494:pharmacology*; D006397:Hematinics / Q000494:pharmacology*; D008854:Microscopy, Electron; D009432:Neural Crest / Q000187:drug effects / Q000196:embryology / Q000648:ultrastructure; D009436:Neural Tube Defects / Q000139:chemically induced / Q000517:prevention & control*; D010672:Phenytoin / Q000008:administration & dosage*
chemical_list: D006397:Hematinics; D010672:Phenytoin; D005492:Folic Acid