Levels of annexin IV and V in the plasma of pregnant and postpartum women.
Annexin (Anx) V is pivotal in the maintenance of pregnancy by preventing the activation of blood coagulation. The homology of the amino acid sequence between Anx IV and Anx V is highest in Anx family proteins. However, little is known about the roles of Anx IV in pregnancy. The aim of this study is to clarify the roles of circulating Anx IV and Anx V in normal pregnancy. Subjects were non-pregnant women (n = 50), 120 pregnant women, and maternal subjects just after delivery (n = 53) or postpartum (n = 67). Anx IV in the plasma of non-pregnant women was at a concentration 20 times that of Anx V. The plasma levels of Anx IV suddenly increase after delivery, but Anx V levels remain low during this period. Anx IV and Anx V exert similar levels of anticoagulant activity. Anx IV protein was expressed on the basal surface of syncytiotrophoblasts; Anx V protein, on the apical surface of syncytiotrophoblasts. These results suggest that Anx IV enters the maternal bloodstream just after delivery and might play a role in preventing disseminated intravascular coagulopathy, and that Anx V helps to prevent clotting in the placenta during pregnancy.
Masuda
Junko
J
Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo, Japan.
Takayama
Eiji
E
Satoh
Ayano
A
Ida
Michiru
M
Shinohara
Tadashi
T
Kojima-Aikawa
Kyoko
K
Ohsuzu
Fumitaka
F
Nakanishi
Kuniaki
K
Kuroda
Koichi
K
Murakami
Mitsutaka
M
Suzuki
Kimihiro
K
Matsumoto
Isamu
I
D000328:Adult; D017314:Annexin A4 / Q000097:blood* / Q000502:physiology; D017304:Annexin A5 / Q000097:blood* / Q000502:physiology; D015415:Biomarkers / Q000097:blood; D001777:Blood Coagulation; D001780:Blood Coagulation Tests; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005342:Fibrinolysis; D006801:Humans; D007150:Immunohistochemistry; D049590:Postpartum Period / Q000097:blood*; D011247:Pregnancy / Q000097:blood*; D011264:Pregnancy Trimesters
D017314:Annexin A4; D017304:Annexin A5; D015415:Biomarkers