The Renin-Angiotensin-Aldosterone System in Pregnancy Response to terbutaline provocation in preeclampsia

The blood pressure control in preeclampsia (PE) was studied in 13 pregnant women with PE and 13 controls. They received a 25 minute i.v. infusion of a fi-adrenergic receptor agonist, terbutaline. A paradoxical decrease of systolic blood pressure was seen in women who had, or later developed, severe PE. Blood samples were analyzed for angiotensin converting enzyme (ACE), atrial natriuretic peptide (ANP), norepinephrine, dopamine, angiotensin II (All), renin, aldosterone, Cortisol. In the PE group the severity of PE correlated well with aldosterone levels and differed significantly compared to the control group (p<0.01). Plasma renin levels were significantly lower in PE compared to controls (p<0.05) which may explain the low aldosterone levels. Aldosterone levels also correlated well with All levels in the PE group but not in the control group (correlation coefficient 0.665, p<0.05). The ACE activity level was increased in PE. Analyses of ANP, norepinephrine, Cortisol did not reveal any clues to the disease. Dopamine levels seemed extremely high in the PE group, and it could be that dopamine depresses the renin-angiotensin-aldosterone system in PE.