Isoxsuprine-induced release of pulmonary surfactant in the rabbit fetus.
Rabbit fetuses were injected intramuscularly with 0.5 mg. of isoxsuprine on the twenty-eighth day of gestation. They were killed in utero four hours after the injection, and fetal pulmonary fluid (FPF) was collected through a tracheal catheter. The quantity of FPF and the lung weight/body weight ratio were both significantly less in the isoxsuprine-treated fetuses than in control fetuses. Surface activity, evaluated with pulsating bubble, and the lecithin/sphingomyelin (L/S) ratio were greater in FPF from isoxsuprine-treated animals than in control samples. We concluded that isoxsuprine is able to dehydrate the fetal lung and cause a release of surfactant stored in type II pneumocytes. This latter conclusion was supported by a significant decrease in the number of lamellar inclusions observed in these cells.
D000653:Amniotic Fluid / Q000378:metabolism; D000818:Animals; D001835:Body Weight; D004848:Epithelium / Q000648:ultrastructure; D005260:Female; D005333:Fetus / Q000502:physiology; D007556:Isoxsuprine / Q000494:pharmacology*; D009929:Organ Size; D010713:Phosphatidylcholines / Q000378:metabolism; D011247:Pregnancy; D011650:Pulmonary Alveoli / Q000648:ultrastructure; D011663:Pulmonary Surfactants / Q000378:metabolism*; D011817:Rabbits; D013109:Sphingomyelins / Q000378:metabolism; D013499:Surface Properties
D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants; D013109:Sphingomyelins; D007556:Isoxsuprine