MORPHOLOGICAL EFFECTS OF CHRONIC BILATERAL PHRENECTOMY OR VAGOTOMY IN THE FETAL LAMB LUNG

  • 1 January 1980
    • journal article
    • research article
    • Vol. 130  (JUN) , 683-695
Abstract
Relationship between fetal respiratory activity and fetal lung development was studied at the cellular level using 2 experimental models. Chronic bilateral phrenectomy over 20-28 days during the last trimester of the fetal lamb resulted in hypoplastic lungs, although cellular maturity, as indicated by the presence of alveolar epithelial type II cells, was present. In lungs from fetal lambs undergoing sham operations for a similar time course there was evidence of enhanced alveolar proliferation when compared to lungs from normal fetal sheep of a similar gestational age. This was most likely due to operative stress. Following chronic bilateral vagotomy no changes in size or histology of the fetal lamb lungs were detected. At an ultrastructural level inclusions of type II cells consistently showed the loss of the typical osmiophilic, lamellated appearance. Apparently fetal breathing apparatus is important in maintaining a volume of lung liquid which is adequate for normal pulmonary development, particularly during the phase in which alveoli are formed.