HYPERTENSION IN PREGNANCY - CHANGES IN ACTIVIN-A MATERNAL SERUM CONCENTRATION

Human placenta is the major source of activin A in maternal circulatio n. The aim of the present study was to evaluate maternal activin A ser um concentration in pregnant women with chronic hypertension (n=14), p regnancy-induced hypertension (n=10) or pre-eclampsia (n=16). In the g roup of pregnant women with chronic hypertension and of healthy pregna nt women (n=10) activin A was measured in samples collected longitudin ally throughout gestation. Using a specific two-site enxyme-linked imm unosorbent assay, it has been possible to measure maternal serum activ in A concentration. In addition, the effect of recombinant human activ in A administration on mean arterial pressure and heart rate in female rats have been also investigated. Mean+/-SEM of maternal serum activi n A concentration in pre-eclamptic women (57.4 +/- 28.3 ng/ml), was si gnificantly higher than in women with pregnancy-induced hypertension ( 14.8 +/- 10.5 ng/ml), chronic hypertension (10.3 +/- 5.4 ng/ml) or hea lthy control women (9.2 +/- 9.4 ng/ml)(P<0.01). Serum activin A levels evaluated 2 weeks after anti-hypertensive treatment were not signific antly different in pre-eclamptic women. Moreover, when exogenous recom binant human activin A was administered in female rats arterial pressu re or frequency of heart rate did not change. The present study showed that maternal serum activin A concentration is abnormally high in pat ients with pre-eclampsia. Thus, since the patients with chronic hypert ension or pregnancy-induced hypertension have activin A concentration in the normal range of values, activin A may, be a prognostic marker o f hypertension in pregnancy.