No abstract available.
Fetal Development*

OBJECTIVE: To investigated whether lowering oxygen tension affects invasion of cultured trophoblast. METHODS: Trophoblasts were isolated from the normal placenta in early pregnancy(6-10 weeks in gestation). Isolated trophoblasts were cultured under normoxic(5% CO2, 95% humid air in incubator) and hypoxic(MERCK, 1% O2, 99% CO2) conditions for 24, 48 and 72 hours, respectively. The proliferation ability was measured using [H3] thymidine assay. Total RNA was extracted from the cultured trophoblasts. The expressions of matrix metalloproteinase(MMP-2) and tissue inhibitor of metallo- proteinase(TIMP-2) were determined by reverse transcription- polymerase chain reaction(RT-PCR) and Northern blot analysis. The invasiveness of cultured trophoblast was observed using in vitro invasion assay. RESULTS: [H] thymidine assay indicated that cellular DNA synthesis was not affected by the culture condition. The expression of MMP-2 mRNA was decreased at 24 hours and then progressively increased in the time-dependent manner in each culture condition. The expression of TIMP-2 was decreased in the time-dependent manner under hypoxic condition. In vitro invasion assay revealed that the cultured trophoblasts under hypoxic condition has more invasive ability than them under normoxic condition. CONCLUSION: These data suggests that hypoxic condition may stimulates the invasion of trophoblast in the human placentation. And MMP-2 and TIMP-2 may be related to control their invasiveness under hypoxic condition.
Blotting, Northern ; DNA ; Humans ; Oxygen ; Placenta ; Placentation ; RNA ; RNA, Messenger ; Thymidine ; Tissue Inhibitor of Metalloproteinase-2 ; Trophoblasts*