Platelet angiotensin II receptor status during pregnancy in Chinese women at high-risk of developing pregnancy-induced hypertension.
OBJECTIVE
The aims of this prospective study were to explore the changes in platelet angiotensin II (A-II) binding in pregnancy amongst Chinese women at high risk of developing pregnancy-induced hypertension (PIH) and the effects of low-dose aspirin and calcium supplementation on A-II binding.


METHODS
Platelet A-II binding was assayed in 15 non-pregnant women and in 63 pregnant women determined to be at risk of PIH on the basis of 2nd-trimester mean arterial pressure (MAP). The pregnant patients were randomized into three groups: control, low-dose aspirin, and calcium supplementation. A-II binding was assayed again during the 3rd trimester in half the women and 8 weeks after delivery.


RESULTS
A-II binding was negatively correlated with MAP measured in the left lateral position (p < 0.05) but not with MAP measured in the supine position. There were no significant differences between A-II binding in non-pregnant and pregnant women. Neither low-dose aspirin nor calcium supplementation caused significant reductions in A-II binding.


CONCLUSIONS
The measurement of platelet A-II binding is unlikely to provide significant information regarding the risk of PIH over and above that obtained from measurement of 2nd-trimester MAP.
Rogers
M S
MS
Department of Obstetrics and Gynaecology, Chinese University, Hong Kong.
Hung
C
C
Arumanayagam
M
M
D000293:Adolescent; D000328:Adult; D000804:Angiotensin II / Q000032:analysis / Q000378:metabolism*; D001241:Aspirin / Q000494:pharmacology / Q000627:therapeutic use*; D001792:Blood Platelets / Q000378:metabolism*; D002118:Calcium / Q000494:pharmacology / Q000627:therapeutic use*; D015331:Cohort Studies; D005260:Female; D005527:Food, Fortified; D006723:Hong Kong; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy / Q000378:metabolism*; D007457:Iodine Radioisotopes; D018579:Patient Selection; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D049590:Postpartum Period / Q000187:drug effects / Q000502:physiology; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000097:blood / Q000188:drug therapy / Q000378:metabolism*; D011262:Pregnancy Trimester, Second / Q000187:drug effects / Q000502:physiology; D011263:Pregnancy Trimester, Third / Q000187:drug effects / Q000502:physiology; D011945:Receptors, Angiotensin / Q000097:blood*
D007457:Iodine Radioisotopes; D010975:Platelet Aggregation Inhibitors; D011945:Receptors, Angiotensin; D000804:Angiotensin II; D001241:Aspirin; D002118:Calcium