Abstract: To investigate expressions of hypoxiainducible factor1α and Endoglin in the placenta and the serum soluble endoglin in preeclampsia. MethodsExpressions of HIF1α and Endoglin in the placenta collected from 40 pregnant women with preeclampsia（including mild and severe preeclampsia）and 20 normal pregnant women were determined by immunohistochemistry. The level of soluble endoglin in the serum was detected by enzyme linked immunosorbent assay. Results①Expressions of HIF1α and Endoglin protein in preeclampsia placenta were significantly higher than those in normal placenta (P<0.01), and were higher in the severe group than those in the mild group (P<0.01). ② The level of sEng in the serum of the preeclampsia group was significantly higher than that of the controls (P＜0.01) and was higher in the severe group than in the mild group(P<0.01). ③In the preeclampsia group, HIF1α expression in the placenta was positively correlated with expression of Endoglin in the placenta(r=0.686) and in the serum level（r=0.866). ConclusionAbnormal excess expression of HIF1α in the placenta may induce high expression of Endoglin in the placenta and sEng in the serum, which may be involved in the pathophysiological processes of preeclampsia.

Key words: Preeclampsia, Placenta, HIF1α, Endoglin, Soluble endoglin