A Prospective Longitudinal Study of Immunoreactive Prostacyclin and Thromboxane Metabolites in Normal and Hypertensive Pregnancy

Publisher Website
Google Scholar
Abstract
Prostacyclin (PGI2) and thromboxane (TxA2) have been implicated in the pathophysiology of PIH. A prospective longitudinal study of maternal plasma levels of PGI2 and TxA2 metabolites measured by radioimmunoassay, was carried out in 14 pregnancies. In the eight pregnancies which remained normal, PGI2 metabolites (PGI2 M) were significantly increased in the first as compared to the second and third trimesters. Six pregnancies were complicated by mild to moderate PIH in the third trimester. PGI2 M levels were not significantly different from the normal group in the first and second trimesters, but fell to unrecordable levels (< 5pg/ml) in all hypertensive patients, with the development of PIH, a feature not seen in any of the normal group. In both groups, levels of TxB2 the stable metabolite of TxA2, fell significantly in the second and early third trimesters. Late third trimester TxB2 levels obtained in the hypertensive group only, were significantly higher than earlier in the third trimester. These results support the hypothesis that PGI2 deficiency is involved in the pathophysiology of PIH.