OBJECTIVETo observe the effect of intra-amniotic administration of pulmonary surfactant (PS) on the lung ultrastructure and expression of surfactant protein A (SP-A) in fetal rabbit with intrauterine infection.

METHODSIntra-amniotic PS injection was administered in a rabbit model of premature rupture of membrane and intrauterine infection induced by intrauterine colibacillus injection on the gestational days 24 and 26 days. The lung ultrastructural changes in the fetal rabbits were observed using electron microscope, and the expression of SP-A was measured with immunohistochemical staining and Western blotting 19.5 h after the PS administration.

RESULTSalveolar type I cell (AT I), alveolar type II cell (AT II). In fetal rabbits with intrauterine colibacillus injection, inflammatory cell infiltration was observed in the pulmonary alveolus, bronchus lumens and intracytoplasm irrespective of PS administration. Compared with those in normal fetal rabbits, the number of alveolar type II cells (AT II) in the lung tissue decreased in fetal rabbits with intrauterine infection, and vacuolization of the lamellar bodies occurred with evidence of cell apoptosis; PS administration resulted in increased number of the AT II cells and lamellar bodies and reduced the cell apoptosis. The expression of SP-A was significantly lower in the infection group than in normal control group (P<0.05), but comparable between the PS group and the control group (P>0.05).

CONCLUSIONChanges in pulmonary alveolar ultrastructure and decreased expression of SP-A occur in fetal rabbits after intrauterine infection, and intra-amniotic administration of PS can alleviate these changes to promote lung maturation.

Amnion ; Animals ; Female ; Fetal Membranes, Premature Rupture ; drug therapy ; Injections ; Lung ; embryology ; metabolism ; ultrastructure ; Pregnancy ; Pregnancy Complications, Infectious ; metabolism ; Pulmonary Surfactant-Associated Protein A ; metabolism ; Pulmonary Surfactants ; administration & dosage ; Rabbits

The aim of this study was to assess the effectiveness of active intervention with antenatal maternal corticosteroid and antibiotics therapy in infants delivered between 24 and 28 weeks of gestation after premature rupture of membrane. This retrospective study included pregnant women complicated by preterm delivery at the Dong-A University Hospital from 1998 to 2002. Patients were divided into labor induction group 1 (n=20), observation group 2 (n=19), and medication group 3 (n=20). We evaluated the effects of prolongation of pregnancy and intervention with maternal corticosteroids and antibiotics therapy on perinatal and neonatal outcomes. Each group did not have a significant difference (p<0.05) in neonatal outcomes, such as respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, retinopathy of prematurity, pneumonia, bronchopulmonary dysplasia, and sepsis. The mean latency period was 4.7 days and 7.6 days in groups 2 and 3, respectively. Therefore, this study was unable to demonstrate any beneficial effects of corticosteroids in improving neonatal outcomes and prolongation of the latency period with antibiotics.
Adrenal Cortex Hormones/*pharmacology ; Adult ; Anti-Bacterial Agents/*pharmacology ; Apgar Score ; Female ; Fetal Membranes, Premature Rupture/*drug therapy ; Gestational Age ; Humans ; Infant, Newborn ; Maternal Age ; Pregnancy ; Pregnancy Outcome ; Pregnancy Trimester, Second ; Premature Birth/prevention & control ; Respiratory Distress Syndrome, Newborn/prevention & control ; Retrospective Studies ; Time Factors