Is maternal copper supplementation during alveolarization protecting the developing rat lung against the adverse effects of maternal nicotine exposure? A morphometric study

In a previous study, it was shown that maternal nicotine exposure during gestation and lactation interfered with alveolarization and resulted in gradual deterioration of the lung parenchyma, resulting in microscopic emphysema. The aim of this study was thus to investigate the long-term effects of maternal nicotine exposure (1 mg/kg body weight/day, subcutaneous [sc] from the onset of the phase of rapid alveolarization, which occur from postnatal day 4 in rats, on (1) the development of the gas-exchange area of the lungs of the offspring and, (2) whether maternal copper supplementation (1 mg/kg body weight/day, SC) during the same period of time will prevent the effect of maternal nicotine exposure on the development of the neonatal rat lung. Nicotine administration lasted until weaning on postnatal day 21. The day of birth was designated day 0. The offspring were exposed to nicotine via the mother's milk only. The experimental animals received no nicotine or copper after postnatal day 21. The lung tissue of the neonates was collected on postnatal days 14, 21, and 42 and prepared for morphometry. The results obtained show that maternal nicotine exposure had no influence on body weight, chest circumference, crown-rump length, and lung volume, but resulted in bigger alveolar volumes and suppressed alveolarization in the lungs of the offspring. Copper supplementation during this period of lung development reduced the adverse effect of maternal nicotine exposure on neonatal lung development. Even though copper reduced the adverse effects of maternal nicotine exposure during this phase of lung development, it did not prevent the induction of microscopic emphysema.