Abstract
To determine airway ion transport in term infants on the first day of postnatal life, and to test the hypothesis that infants born without labor have reduced sodium absorption, we measured nasal potential difference using a modified perfusion protocol suitable for newborn infants. We examined maximal stable baseline potential difference, the change after perfusion with 10−4 M amiloride (Δamil), and the change after perfusion with a zerochloride solution (Δzero Cl−) in infants born after elective cesarean section (n = 21) or normal labor (n = 20). Maximal stable baseline potential difference was not different in the two cohorts (−24.0 mV, range −9 to −64 mV versus −25.5 mV, range −6 to −44 mV). The majority of infants in both cohorts showed a substantial fall in potential difference after amiloride perfusion, and there was little capacity for chloride secretion. These results demonstrate a fluid absorptive pattern in the airways on the first postnatal day. In these well infants, the ion transport phenotype was not dependent on the presence or absence of labor.
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Abbreviations
- PD:
-
potential difference
- ENaC:
-
epithelial sodium channel
- RDS:
-
respiratory distress syndrome
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Acknowledgements
The authors thank the families who supported this project. We also thank Dr. Pierre Barker, University of North Carolina at Chapel Hill, who was the driving force behind the development of this infant nasal PD system, and the staff on the Neonatal Intensive Care Unit at the Liverpool Women's Hospital for their support.
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Supported by a grant from the Liverpool ‘Newborn Appeal' (E.A.G.).
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Gaillard, E., Shaw, N., Wallace, H. et al. Airway Ion Transport on the First Postnatal Day in Infants Delivered Vaginally or by Elective Cesarean Section. Pediatr Res 54, 58–63 (2003). https://doi.org/10.1203/01.PDR.0000069842.09976.CB
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DOI: https://doi.org/10.1203/01.PDR.0000069842.09976.CB
