Discussion
GRα C is the isoform involved in glucocorticoid induced apoptosis and suggests that its predominance in preterm placentae may contribute to the pathophysiology of preterm birth.
Methods
Preterm (24-36 completed weeks of gestation, n = 55) and term placentae (>37 completed weeks of gestation, n = 56) were collected at delivery. Placental GR expression was examined using Western Blot and analysed in relation to gestational age at delivery, fetal sex, birthweight and betamethasone exposure. Data was analysed using non-parametric tests.
Results
Eight known isoforms of the GR were detected in the preterm placenta and include GRα (94 kDa), GRβ (91 kDa), GRα C (81 kDa) GR P (74 kDa) GR A (65 kDa), GRα D1-3 (50-55 kDa). Expression varied between preterm and term placentae with a greater expression of GRα C in preterm placentae relative to term placentae. The only sex differences in preterm placentae was that GRα D2 expression was higher in males than females. There were no alterations in preterm placental GR expression in association with betamethasone exposure.