title: Effects of cis-hydroxyproline on type II cell development in fetal rat lung.
abstract: The role of collagen in pulmonary epithelial cell division and differentiation during lung development was investigated by injecting the proline analogue cis-hydroxy-L-proline (cis-HYP) to timed pregnant rats. Lung weight, DNA and 3H thymidine incorporation were unchanged when compared to controls; epithelial cell division, determined by autoradiography, was also unchanged. However air sac development and phospholipid synthesis by epithelial cells were retarded in cis-HYP treated animals. The percentage of epithelial cells containing lamellar bodies was reduced at days 20-22 of gestation and the level of disaturated phosphatidylcholine (DSPC) was also significantly lower in treated rats. A sex-related difference was not eliminated by cis-HYP treatment, lung maturation was still more rapid in females. Non-dialysable hydroxyproline levels were decreased, and morphologically, less fibrillar collagen was seen at the epithelial-interstitial cell interface, though direct cell-cell contacts were not reduced. The results indicate that the injection of cis-HYP did not alter lung growth, but caused a reduction in fibrillar collagen which was associated with reduced surfactant synthesis by Type II epithelial cells.
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D003094:Collagen / Q000502:physiology; D004847:Epithelial Cells; D005260:Female; D005865:Gestational Age; D006909:Hydroxyproline / Q000494:pharmacology*; D008168:Lung / Q000196:embryology* / Q000378:metabolism; D008297:Male; D008648:Mesoderm / Q000166:cytology; D010713:Phosphatidylcholines / Q000378:metabolism; D011247:Pregnancy; D011650:Pulmonary Alveoli / Q000166:cytology*; D011663:Pulmonary Surfactants / Q000378:metabolism*; D051381:Rats
chemical_list: D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants; D003094:Collagen; D006909:Hydroxyproline