Figure 3.

Heparin administration in nonpregnant women dramatically increases the 100-kDa sFLT1 isoform. A, Western blotting demonstrated that sFLT1 was the predominant isoform in plasma from never-pregnant women, whereas sFLT1 and sFLT1–14 are both present in plasma from normal pregnant (NP) and preeclamptic (PE) women. Coomassie blue staining on the lower blot demonstrates that three times more sample was loaded into lanes from never-pregnant women because sFLT1 concentrations in nonpregnant women are lower than sFLT1 concentrations in pregnant and preeclamptic women. B, The dramatic increase in sFLT1 after heparin administration was confirmed by Western blotting. A single sFLT1 band was seen at 100 kDa after heparin administration to three different nonpregnant women. The upper blot shows a normal exposure. The lower blot was intentionally overexposed to demonstrate very low levels of sFLT1 before heparin administration. C, Lanes 1 and 2 show both 100- and 145-kDa sFLT1 bands from separately run villous placental homogenates from two women with preeclampsia. In contrast, a single 100-kDa band was obtained from post-heparin plasma pooled from four nonpregnant women. The upper blot shows a normal exposure, whereas the lower blot was intentionally overexposed.