title: Exhaled nitric oxide is associated with postnatal adaptation to hypoxia in Tibetan and non-Tibetan newborn infants.
abstract: OBJECTIVE
  This Chinese study assessed partial pressure of exhaled nitric oxide (PeNO) in healthy Tibetan and non-Tibetan newborn infants born at a very high altitude.
  
  
  METHODS
  Full-term Tibetan and non-Tibetan neonates born in Lhasa, 3658 metres above sea level, were compared to non-Tibetan neonates born in Kunming (1891 m) and Huai'an (16 m). The chemiluminiscence technique was used to measure the fraction of exhaled nitric oxide during spontaneous tidal breathing and this was then converted to partial pressure of exhaled nitric oxide (PeNO).
  
  
  RESULTS
  In their first week, Tibetan and non-Tibetan neonates born in Lhasa had persistently higher PeNO levels than non-Tibetan neonates born in Kunming and Huai'an, which was further verified by partial pressure of inspired oxygen adjustment. However, the non-Tibetans born in Lhasa required short-term oxygen therapy to improve their early postnatal oxygenation. The temporal changes of PeNO and cardio-respiratory function measurements demonstrated that Tibetan and non-Tibetan newborns in Lhasa initially needed to adapt to attain homoeostasis in oxygenation and gas exchange.
  
  
  CONCLUSIONS
  Tibetan and non-Tibetan newborn infants living at the same high altitude demonstrated comparable PeNO levels during postnatal adaptation to hypobaric hypoxia, which warrants further investigation of the mechanism of endogenous nitric oxide and hypoxic tolerance.
authors.affiliation: Department of Pediatrics, Children's Hospital of Fudan University, and the Laboratory of Neonatal Medicine of National Health and Family Planning Commission, Shanghai, China.
authors.forename: Panpan
authors.initials: P
authors.lastname: Wu
authors.affiliation: Department of Pediatrics, Tibet Autonomous Regional People's Hospital, Lhasa, Tibet, China.
authors.lastname: Shanminna
authors.affiliation: Department of Pediatrics, First General Hospital of Kunming Medical University, Kunming, Yunnan, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Liang
authors.affiliation: Department of Pediatrics, Huai'an Women and Children's Hospital, Huai'an, Jiangsu, China.
authors.forename: Hongni
authors.initials: H
authors.lastname: Yue
authors.affiliation: Department of Pediatrics, Children's Hospital of Fudan University, and the Laboratory of Neonatal Medicine of National Health and Family Planning Commission, Shanghai, China.
authors.forename: Liling
authors.initials: L
authors.lastname: Qian
authors.affiliation: Department of Pediatrics, Children's Hospital of Fudan University, and the Laboratory of Neonatal Medicine of National Health and Family Planning Commission, Shanghai, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Sun
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000531:Altitude; D015415:Biomarkers / Q000378:metabolism; D001944:Breath Tests; D002681:China; D005260:Female; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D007231:Infant, Newborn; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism*; D010101:Oxygen Consumption; D010313:Partial Pressure; D018609:Tibet
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide
keywords: Adaptation; High altitude; Hypoxia; Neonate; Nitric oxide