K. Asabe et al., AN IMMUNOHISTOCHEMICAL STUDY OF THE EXPRESSION OF SURFACTANT APOPROTEIN IN THE HYPOPLASTIC LUNG OF RABBIT FETUSES INDUCED BY OLIGOHYDRAMNIOS, The American journal of pathology, 145(3), 1994, pp. 631-639
We shunted amniotic fluid from alternate gestational sacs into the mat
ernal peritoneal cavity between 23 and 30 days gestation in fetal rabb
its (full term, 31 days) to investigate the effect of oligohydramnios
on surfactant apoprotein A (SP-A) expression by an immunohistochemical
morphometric analysis. The amniotic shunt produced a significant decr
ease in the amniotic fluid volume (P < 0.02), as well as a reduction i
n the lung weight (P < 0.005) and lung/body weight ratio (P < 0.001),
which indicated lung hypoplasia. These fetuses also showed a statistic
ally significant reduction of SP-A expression, ie, SP-A-positive type
II cells per unit area (P < 0.05), SP-A-positive type II cells/total c
ells ratio (P < 0.001), the percentage of SP-A-positive area per unit
area (P < 0.005), and the SP-A-positive area/alveolar epithelium area
plus the lung interstitium area ratio (P < 0.005). These results sugge
st that oligohydramnios significantly retards and modifies the structu
ral growth and functional development of alveolar type II cells in SP-
A expression. This animal model of hypoplastic lung in fetuses is thus
considered to be useful in helping to further develop the treatment f
or hypoplastic lung.