Respiratory distress syndrome in copper deficiency: an experimental model developed in rats.

An experimental model has been developed to investigate the effect of copper deficiency on lung maturity in the newborn rat. Three groups of female Sprague-Dawley rats were used: the copper-deficient group was fed with a copper-free diet; the control group received a copper-adequate diet, and the pair-fed group was fed with a limited copper diet. After gestation and delivery, 35% of the newborn copper-deficient group showed respiratory distress syndrome (RDS). The neonatal lungs were isolated and processed for ultrastructural and biochemical study: A greater thickness of the air-blood barrier was observed in the lungs of the copper-deficient group, however, no other differences were observed in the rest of the pulmonary structures. Quantitative differences in pulmonary surfactant were not found in the three groups. The thickness of the air-blood barrier might explain the RDS observed in the copper-deficient newborns.