To determine the correlation between renin-angiotensin-aldosterone(RAA)and atrial natriuretic peptide(ANP)in the maternal and fetal plasma of pregnant women with pregnancy-induced hypertension(PIH)

and their role in the pathogenesis of PIH.The maternal and fetal plasma ren in activity(PRA)

angiotensin Ⅱ(AngⅡ)

aldosterone(Adl)and atrial natriuretic peptide(ANP)were measured in 26 pregnant women withPIH(PIH group)and 30 pregnant women with normotension(Control group )by radioimmunoassay (RIA).ResultsBoth the maternal and umbillical vein (UV)plasma concentration of PRA

Ⅱ

Ald andANP in PIH groupwere significantly elevated when compared with parameters in control group(P<0

05).Farthermore

the levels of PRA

AngⅡ

Ald and ANP in the UV were significantly higher than those in the maternal vein(P<0.05).We alsofound a negative correlation between RAA and ANP in control group(P<0.05).but this kind of correlation didnot exist in PIH group(P<0.05).Conclusion:These results suggested that the RAA

especialy those of fetus-placental unit play an important role in the pathogenesis of PIH

and that the imbalance of the relationship between RAA and ANP also had an important role at the onset of PIH.So we postulated that highlyactive ANP(haANP)and atriopeptidase inhibitor would be effective in treating patients with PIH.