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Prenatal nicotine exposure impairs postnatal sensitivity to hypoxia and hypercapnia
Author(s) -
Fregosi Ralph,
Huang YuHsien,
Brown Amanda,
CostyBennet Seres
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.6.a1444-b
Subject(s) - hypercapnia , nicotine , hypoxia (environmental) , asphyxia , hyperoxia , medicine , anesthesia , in utero , chemoreceptor , endocrinology , ventilation (architecture) , respiratory system , fetus , pregnancy , chemistry , biology , lung , oxygen , mechanical engineering , receptor , organic chemistry , engineering , genetics
Data on the influence of prenatal nicotine exposure on the postnatal development of hypoxic and hypercapnic sensitivity are equivocal. We previously presented preliminary data showing some abnormalities in the response to hypercapnia and hypoxia in nicotine‐exposed neonatal rats. Here, we report the responses to hypoxia (10% inspired O2), hyperoxia (100% O2), hyperoxic hypercapnia (9% CO2, 50% O2, balance N2) and asphyxia (12% O2, 5% CO2, balance N2) in 26 neonatal rats; 13 underwent in utero saline exposure, and 13 in utero nicotine exposure. Each animal was studied on postnatal days 1,3,6,9,12 and 18 with head‐out body plethysmography. Ventilatory responses were analyzed with 3‐factor ANOVA, with treatment, age and test gas the main factors. Nicotine‐exposed pups showed blunted ventilatory responses to hypoxia on days 3 and 9, but a larger response on day 18. The drop in ventilation in response to hyperoxia was blunted on days 6 and 9 in nicotine‐exposed pups, but they showed a larger drop on day 18. Nicotine blunted the ventilatory response to hypercapnia on days 6 and 12, while the change in ventilation with asphyxia was significantly blunted only on day 1. Prenatal nicotine exposure impairs the development of chemoreceptor reflexes, with manifestation of the developmental abnormalities dependent on both age and stimulus modality.