Platelet angiotensin II binding sites in normotensive and hypertensive women

Abstract

Summary. Specific binding of angiotensin II (AII) to platelets was measured in 89 women, 25 nulliparous non-pregnant women and 64 primigravida in the third trimester of pregnancy. There was significantly lower binding in the 25 pregnant women who were normotensive (2.3 fmol/10⁹ cells) when compared with the non-pregnant women (9.0 fmol/10⁹ cells P9 cells) when compared with the 25 normotensive pregnant women (P9 cells), when compared with the 16 who had non-proteinuric PIH, (4.6 fmol/10⁹ cells) although the difference was not statistically significant (P<0.04). The pressor response to AII is also diminished in pregnancy, yet less so if pregnancy induced hypertension develops. Platelets may provide a readily accessible tissue with which to study AII responsiveness in pregnancy.