RESUMEN
Objective To investigate the roles of placental cellular apoptosis and bcl-2 gene expression in fetal growth restriction (FGR) with unclear etiologies. Methods The placental tissues of 15 FGR and 15 parallel normal pregnancies were included in the study. Apoptosis were evaluated by terminal deoxynucleotidyl transferasc-mediated deoxyuridine tripbosphate nick end labeling (TUNEL) assay, transmission electron microscopy and flow cytometry assay (FCM). Expression of bcl-2 was determined by RT-PCR. Results In cells from FGR placentas, but not in control normal cells, typical features of apoptosis were observed, including intemucleosomal DNA degradation, and both nuclear (nuclear condensation and fragmentation) and extranuclear (cell blebbing) morphological alterations. The placental cellular apoptosis were also confirmed at a rate of 13.68% by TUNEL assay and 10. 58% by FCM in FGR group, compared to 4. 05% and 3.88% in the normal tissues. Meanwhile, bcl-2 expression level was lower in FGR group (0. 19±0. 13) than in the normal group (0. 55±0. 17). Conclusion Apoptosis may play an important role in the pathogenesis of FGR and may be related with to lowered expression of bcl-2.