CHANGES IN LUNG STRUCTURE AND CELLULAR DIVISION INDUCED BY TRACHEAL OBSTRUCTION IN FETAL SHEEP

Abstract

Increased expansion of the fetal lung, caused by obstruction of the fetal trachea, is a potent stimulus for growth and structural development of the fetal lung. Our aim was to analyze the changes in lung structure induced by fetal tracheal obstruction and to identify cell types that contribute to the growth response. Fetal sheep were exposed to 2, 4, or 10 days of tracheal obstruction (TO) and on day 128 of gestation (term "147 d"), were injected with ³H-thymidine 8 hours before tissues were collected. The right lung was fixed at 20 cm H₂