title: Perinatal anatomic development of alveolar type II cells in rats.
abstract: We studied the perinatal development of rat alveolar type II cells. The volume density (Vv) of lamellar bodies increased twofold from gestational day 21.5 to postnatal day 1 and 1.6-fold between age 1 and 60 days. The Vv of glycogen areas fell sharply between late gestation and postnatal day 1; this decrease was greater in pups delivered from dexamethasone- compared with diluent-treated dams. In utero administration of glucagon to fetuses on gestational day 21.5 caused a decline in the Vv of glycogen areas within 4 h. Pups from dams underfed in late gestation had a higher Vv of glycogen areas and a lower Vv of lamellar bodies on the first 2 postnatal days compared with pups from dams allowed food ad libitum. We conclude that rat alveolar type II cells are somewhat immature at birth; prenatal maternal underfeeding slows the pre- and postnatal maturation of alveolar type II cells; and 3) exogenous glucagon causes a fall in the Vv of glycogen areas in type II cells of fetal rats at gestational day 21.5.
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D002477:Cells / Q000145:classification; D003907:Dexamethasone / Q000494:pharmacology; D005260:Female; D005333:Fetus / Q000502:physiology*; D005934:Glucagon / Q000378:metabolism / Q000494:pharmacology; D008168:Lung / Q000378:metabolism; D009748:Nutrition Disorders / Q000378:metabolism / Q000473:pathology; D010500:Perinatology; D011247:Pregnancy; D011248:Pregnancy Complications; D011650:Pulmonary Alveoli / Q000166:cytology / Q000196:embryology* / Q000254:growth & development; D051381:Rats
chemical_list: D003907:Dexamethasone; D005934:Glucagon