Oligohydramnios decreases platelet-derived growth factor expression in fetal rat lungs.

Objectives: To evaluate the effects of experimental oligohydramnios on lung growth, PDGF and its receptors expressions, and lung morphology in fetal rats. Study Methods: On day 16 of gestation, we anesthetized timed pregnant Sprague-Dawley dams, punctured the uterine wall and fetal membranes of each uterine sac, which resulted in oligohydramnios. Fetuses in the opposite uterine horn served as controls. On days 19 and 21 of gestation, the fetuses were delivered by cesarean section and weighed, and the lungs were dissected free and weighed.
Results: Rats exposed to oligohydramnios exhibited significantly lower lung/body weight ratios on days 19 and 21 of gestation and significantly lower radial saccular counts on day 21 of gestation than did the control rats. Lung PDGF-A and -B gene and protein expressions and elastin level were significantly decreased in rats exposed to oligohydramnios on days 19 and 21 of gestation. PDGF receptor (PDGFR)- and - gene expressions were significantly decreased in rats exposed to oligohydramnios on day 19 of gestation. Conclusion: Decreased PDGF expression may be important in the pathogenesis of oligohydramnios-induced pulmonary hypoplasia and suggest that supplementation may provide useful therapeutic strategies.