Delayed ultrastructural lung maturation in the fetal and newborn hypothyroid (Hyt/Hyt) mouse

Abstract

Thyroid hormones influence fetal and neonatal lung growth and maturation. However, the effect of naturally occurring, genetically determined hypo- or hyperthyroidism on fetal or neonatal lung maturation has not been examined. In the hyt/hyt mouse, primary hypothyroidism, which is characterized by a high serum TSH concentration, is transmitted as an autosomal recessive trait. It occurs due to a mutational defect in the 3-subunit of the TSH receptor. We studied the lung ultrastructure of the fetal [18-d-gestation (term = −19.5 d)] and neonatal (