Part of the book: Recent Advances in Research on the Human Placenta
Placenta is a transient organ ensuring the intrauterine development of the individual. To meet fetal requirements, rapid and continuous cell proliferation enlarges the areas of tissues maintaining maternofetal transport. The cell division in placenta is accompanied with shortening of telomeres leading to cell senescence. Telomerase activity, on the other hand, ensures replication of telomeres and allows the organ to serve till the end of pregnancy. This balanced process may be negatively influenced by unfavorable circumstances. Here, we summarize available data on telomere length as well as telomerase activity in placentas from normal and complicated pregnancies; attention is also paid to the comparison of methods used in relevant studies.
Part of the book: Telomerase and non-Telomerase Mechanisms of Telomere Maintenance
Placental capillary bed plays a key role in the bidirectional transport between mother and fetus. Its continuous growth and maturation accompany fetal growth and meet all fetal requirements to secure fetal well-being. Considerable growth of both capillary bed and area of villous syncytiotrophoblast comes on in third trimester of pregnancy, continues until the end of pregnancy, and is expressed by rapid development of terminal villi. The presented structural and quantitative data show enhanced villous capillary branching, higher proportion of capillaries displaying delayed maturation, and lower proliferative potential of cells forming capillary wall and cytotrophoblast in diabetic placenta at term. Too few studies have focused on the impact of other pathologies, i.e., preeclampsia and IUGR on development of placental capillary bed. The further research may contribute to better understanding of those disorders connected with pregnancy.
Part of the book: Microcirculation