title: Effects of transcutaneous electrical nerve stimulation on fetal and placental development in an experimental model of placental insufficiency.
abstract: OBJECTIVE
  To elucidate the effects of transcutaneous electrical nerve stimulation (TENS) in pregnancies with placental insufficiency.
  
  
  METHODS
  Pregnant rats were subjected to uterine artery ligation and to TENS according to the following groups: ligated stimulated (LS); ligated non-stimulated (LN), control stimulated (CS); and control non-stimulated (CN). Fetal external measurements, such as crown-rump length (CRL), fronto-occipital distance (FOD), thoracic ventral-dorsal (TVDD) and abdominal ventral-dorsal (AVDD) distances were analyzed together with the area occupied by fetal internal organs. Glucose transporter 1 (GLUT-1) expression was evaluated by immunohistochemistry in fetal organs. Thickness of junctional, labyrinth and intermediate placental zones was analyzed by morphometric evaluation in HE-stained slides, and placental hypoxia-inducible factor 1 alfa expression was measured by real-time polymerase chain reaction.
  
  
  RESULTS
  In LN and CS groups compared to the CN group, CRL was reduced (27.51/28.95 versus 30.16 mm), as well as FOD (6.63/6.63 versus 7.36 mm), AVDD (7.38/8.00 versus 8.61 mm) and TVDD (6.46/6.87 versus 7.23 mm). Brain GLUT-1 expression was higher in LS (1.3%) and CS (1.8%). The area occupied by placental vessels in the labyrinth zone (29.67 ± 3.51 versus 20.83 ± 7.63) and intermediate zone (26.46 ± 10.21 versus 10.86 ± 8.94) was larger in the LS group than in the LN group.
  
  
  CONCLUSIONS
  Our results suggest a negative effect of TENS on placental development, thus compromising the maintenance of adequate blood flow to the fetus.
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Camila S O
authors.initials: CS
authors.lastname: Guimarães
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Bruno B F
authors.initials: BB
authors.lastname: Gomes
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Rafael A
authors.initials: RA
authors.lastname: Oliveira
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Leandro R
authors.initials: LR
authors.lastname: Yamamoto
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Laura P
authors.initials: LP
authors.lastname: Rocha
authors.affiliation: b Nephrology Division , Federal University of São Paulo (UNIFESP) , São Paulo , Brazil , and.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Glória
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Juliana R
authors.initials: JR
authors.lastname: Machado
authors.affiliation: b Nephrology Division , Federal University of São Paulo (UNIFESP) , São Paulo , Brazil , and.|c Department of Immunology , Institute of Biomedical Sciences IV, University of São Paulo (USP) , São Paulo , Brazil.
authors.forename: Niels O S
authors.initials: NO
authors.lastname: Câmara
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Marlene A
authors.initials: MA
authors.lastname: Reis
authors.affiliation: a General Pathology Discipline, Biological and Natural Sciences Institute, Triângulo Mineiro Federal University , Uberaba , Brazil .
authors.forename: Rosana R M
authors.initials: RR
authors.lastname: Corrêa
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D000860:Hypoxia / Q000378:metabolism; D010920:Placenta / Q000378:metabolism; D021041:Placental Circulation; D010927:Placental Insufficiency / Q000628:therapy*; D010929:Placentation; D011247:Pregnancy; D017208:Rats, Wistar; D004561:Transcutaneous Electric Nerve Stimulation / Q000009:adverse effects*; D014599:Uterus / Q000098:blood supply
chemical_list: D015415:Biomarkers
keywords: Hypoxia; IUGR; TENS; perfusion; placenta; pregnancy