Platelet activation in the hypertensive disorders of pregnancy

Plasma microparticles and vascular disorders

“…As might be anticipated, microparticle levels are elevated in normal pregnancy; however, reported differences between normal pregnancies and pre‐eclampsia have been inconsistent. Unexpectedly, two studies found reduced PMP levels in pre‐eclampsia (Harlow et al , 2002; Bretelle et al , 2003) despite equivalent circulating platelet counts and increased platelet activation, as measured by the expression of P‐selectin. PMP have been shown to bind to fibrin and it is possible that this reduction in PMP may reflect their consumption in the fibrin deposits found in pathological placental beds.…”

“… References: (1) Jimenez et al (2001), (2) Jimenez et al (2003b)), (3) Gonzalez‐Quintero et al (2003), (4) Gonzalez‐Quintero et al (2004), (5) Chirinos et al (2005), (6) Mallat et al (2000), (7) Bernal‐Mizrachi et al (2003), (8) Amabile et al (2005), (9) VanWijk et al (2002a), (10) Shet et al (2003), (11) Faure et al (2006), (12) Koga et al (2005), (13) Simak et al (2004), (14) Simak et al (2006), (15) Combes et al (1999), (16) Sabatier et al (2002b)), (17) Dignat‐George et al (2004b)), (18) Bretelle et al (2003), (19) Pereira et al (2006),(20) Nomura et al (2005), (21) Ogata et al (2006), (22) Hugel et al (1999), (23) Villmow et al (2002), (24) Harlow et al (2002). …”

Premature labor: a state of platelet activation?

“…There is a solid body of evidence supporting platelet activation in patients with preeclampsia and fetal growth restriction [1,9,11,13,38,48,50,59,62,64,65,74,75,82,86,88,96,99,102,108,116,128,137]. Indeed, elevated maternal plasma and platelet expression of markers for platelet activation, including P-selectin (CD62p) [48,68,74,75,86,128,137,138], Annexin V [34,50,128], and sCD40L concentrations [2,78,95,104], were reported in patients with these pregnancy complications. However, maternal platelet activation in women with preterm labor has not been studied extensively.…”

“…There are inconsistent reports concerning the degree of platelet activation and the release of vasoactive products during normal pregnancy [8,51,60,113,114]. Women who develop obstetric complications, such as preeclampsia and fetal growth restriction, have a higher degree of platelet activation than both normal pregnant and non-pregnant women [1,9,11,13,38,48,50,59,62,64,65,74,75,82,86,88,96,99,102,108,116,128,137]; however, little information is available regarding the association between maternal platelet activation and preterm labor (PTL) [117].…”

Platelet Adhesion and Thrombus Formation in Whole Blood at Arterial Shear Rate at the End of Pregnancy

“…It has also been shown that adhesion of washed platelet onto fibrinogen in static conditions increases during pregnancy, possibly due to changes in the expression of the fibrinogen receptor GPIIb/IIIa . Conversely, other studies do not report platelet hyperaggregability in normal pregnancy . The basal platelet cAMP level was found unchanged during pregnancy in two studies .…”