AJP - Endocrinology and Metabolism, Vol 242, Issue 6 378-E383, Copyright © 1982 by American Physiological Society
Thyroid hormones, malnutrition, and biochemical composition of developing rat lung
J. Ruel, P. Coulombe and J. H. Dussault
We studied the effects of thyroid hormones and malnutrition on protein,
DNA, and phospholipid content of the developing rat lung during the first
month of life. Neonatal hypothyroidism significantly decreases the lung
phospholipid content by 30-45% between 5 and 30 days of age whether the
results are expressed per milligram DNA or per gram tissue. Administration
of thyroxine for 3 days to hypothyroid rats increases significantly (20%)
their total phospholipid content, mainly through its preferential effect on
phosphatidylcholine (50% increase). Adult animal response to thyroid
hormones is markedly different from that observed in young rats for most
parameters examined. In malnourished rats, lung tissue phospholipids are
decreased per cell but not per unit cell mass after 11 days of age. These
results show that hypothyroidism has a specific effect on lung
phospholipids during the neonatal period.
