Transuterine Fetal Tracheal Occlusion Model in Mice.

Fetal tracheal occlusion (TO), an established treatment modality, promotes fetal lung growth and survival in severe congenital diaphragmatic hernia (CDH). Following TO, retention of the secreted epithelial fluid increases luminal pressure and induces lung growth. Various animal models have been defined to understand the pathophysiology of CDH and TO. All have their own advantages and disadvantages such as the difficulty of the technique, the size of the animal, cost, high mortality rates, and the availability of genetic tools. Herein, a novel transuterine model of murine fetal TO is described. Pregnant mice were anesthetized, and the uterus exposed via a midline laparotomy. The trachea of selected fetuses were ligated with a single transuterine suture placed behind the trachea, one carotid artery, and one jugular vein. The dam was closed and allowed to recover. Fetuses were collected just before parturition. Lung to body weight ratio in TO fetuses was higher than that in control fetuses. This model provides researchers with a new tool to study the impact of both TO and increased luminal pressure on lung development.