|
KMID : 0371919910040010179
|
|
Journal of Wonju College of Medicine
1991 Volume.4 No. 1 p.179 ~ p.190
|
|
|
Ultrastructural Study on the Differentiation of Rat Lung
|
|
|
|
|
Abstract
|
|
|
Light and electron microscopy were introduced to examine the differentiation of the rat lung from the fetal stage to the newborn or adult stage. The purpose of th~ present study is to investigate the ultrastructural changes of the alveolar epithelium during the develop-mental processes.
The results indicate as follows : at the 16th day of gestation, fetal rat lung showed glandular structure. And at this stage, the pulmonary epithelial cells were composed of cuboidal or columnar cells. At 20 to 21 days of gestation, the premature alveoli were showed but, the glandular structure was not observed. The pulmonary epithelial cells were attenuated to the thin and flat type I pulmonary epithelial cells at birth The lamellar body, surfactant or the precursor of surfactant, was first observed at the 19th day of gestation and was released to the lumen of alveoli at the 21st day of gestation. At birth, the pulmonary alveoli were well developed and the cuboidal and flat epithelial cells constituted the alveolar epithelium.
In conclusion, the rat lung have been commenced to differentiate from the 16th day of gestation and the shape of pulmonary epithelial cells was changed from cuboidal(type II) form to flat(type I).
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|