[Concentration of follistatin in maternal serum at term and its expression in placenta]
Tao Shang1, Liang Zhao, Hui Li
1Department of Obstetrics and Gynecology, Second Affiliated Hospital, China Medical University, Shenyang 110001, China.
Objective:
To investigate the possible origin and role of follistatin (FS) in pregnancy.
Methods:
The maternal serum FS levels in menstrual cycle, first trimester (8 - 12 weeks) and term (38 - 41 weeks) were determined by a specific two-site enzyme-linked immunosorbent assay (ELISA). Reverse transcription-polymerase chain reaction (RT-PCR) method was utilized to semi-quantitatively determine FS mRNA levels in the ovaries and placentas.
Results:
Maternal serum FS level at term was significantly higher than that in the first trimester of pregnancy and that in normal women during the menstrual cycle (180 +/- 26) micro g/L, (4.4 +/- 2.1) micro g/L, (1.5 +/- 2.2) micro g/L, (respectively P < 0.001). Both placentas and ovaries expressed FS mRNA. Semi-quantitative RT-PCR showed that the expression levels of FS mRNA in placenta were higher than that in ovary of same period, but lower than that in ovary of menstrual phase (0.8 +/- 0.4, 0.4 +/- 0.3, 0.93 +/- 0.13, respectively P < 0.05).
Conclusion:
Fetal-placental unit may be the major source of maternal serum FS. The relatively higher levels of FS in the placentas at term may reflect important roles in modulating the development of embryo and the function of placenta.


